A E I PL T . — E ARTH P LLAR Allt Dear Fochab ers . I g, MEMOIRS OF THE GEOLOGICAL SURVEY.

S C O T L A N D .

T H E G E O L O G Y

LO WER STRATHSPEY

(EXPLANATION OF SHEET

HINXMAN B . A. L . W. , ,

GRA N O N J . S . T WIL S

WITH

PETROLOGICAL C HAPTER AND NOTES BY

M E D SC. J . S . F E M .A. . C.M . . L TT , , ,

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ne hillin /n Price O S g a d Six ence. i p

P R E F A C E

THIS m emoir des cribes the geology of the area inclu ded in Sheet 8 5 of the - c ma Of S t a which mb rac s the t t Of one in h p co l nd , e e dis ric

' w St ath and a ac t tracts in the c u t s of E n Ban fi Lo er r spey dj en o n ie lgi , , A an d . un w as i l ma d Mr. Hinxm an berdeen The gro d or gina ly ppe by ,

Mr. J . S . G a t so Mr. an d at a su s u t at r n Wil n , and Linn , b eq en d e

' the a a o cu the Ban fishire s s Of the c a s c sts re c pied by erie ryst lline hi ,

the ut - ast a t of the Sh t was re- xam Mr in so h e p r ee , e ined by

Wils on .

Fl tt ha c t ut a c a t a t . the Dr. e s on rib ed h p er (Ch p er VII ) on petro graphy of the plu tonic m as ses and certain types Of the metamorphic

an d the c tact m t m m u c the u s rocks , on on e a orphis prod ed by igneo l e a n his m aterials he s t the a a for intru s ions . While pr p ri g vi i ed re

h u of tu n m Of th n m a In the t e p rpose s dyi g so e e phe o en field .

F R. . for his S c a t a s are d ue to DI a u a . S t pe i l h nk Tr q ir , , repor on the f s fis s of the Old R d S a st of Sc t a an d the t o sil he e nd one o l nd, lis R Mr. . Kid st n F R Of the fis s u at Sceat C ai to o . .S . for he fo nd r g; , , his notes on the fos s il plants Of the Old Red Sand stone of S cotland 5

n d to Mr. a a a E Who u a st a T ylor, Lh nbryde , ne r lgin , has s pplied li of the fishes found by him at variou s localities in that formation in the Sheet . The three Plates have been prepared frOm photographs taken by

r u of the G ca Su an d the B a M . L nn , eologi l rvey , ibliogr phy given in

Mr Hinx m an . the Appendix has been compiled By .

H . The m an u s cript has been edited by Mr. orne

J . J . H . EA T LL ,

Direc tor. GICAL S RVE OFFICE GEOLO U Y ,

ONDON 1 6th Januar L , y,

C O N T E N T S .

AGE P . PREFA E C ,

I CHAPTE R .

A a Em ac d in th M a F m f the G un d Hi s Ri re br e e p . or o ro , ll , ver S st ms a s y e , L ke ,

F atu s d ue to utc Geological Features and Surface Relief . e re o rop f d iff e c —t fau ti —to acia acti D ai a o er nt ro ks o l ng gl l on. r n ge s st m— a e O f i r- le G ica st u ct u in y e g r ve val ys . eolog l r re ati t o P u ati and E c n mics rel on op l on o o ,

C HAPTER II I .

F m ati ns an G u f G a ica St uctu or o d ro ps o Rock . ener l Geolog l r re of A a re ,

C HAPTER IV.

’ M AMOR H C ROC KS—Ban shire S i s ET P I fl er e , uart z it — im st B ac Schist —Mica Schis t C a Q e L e one l k , l y S at and Ph it l e, yll e .

V CHAPTER .

G a u it ic S chists of the C t a Hi h a d s r n l en r l g l n , — Nome nclat ure general lithological character and structure d s c i ti of t i a ti e r p on yp c l s ec ons .

I GNEOUs ROC KS ,

P i ci s of C lassification —O d P ut ic masses—E dio r n ple _l er l on pi — it s Ga b and S t i F iat d G anit . N w r e , b ro, — erpen ne ol e— r e e er Pl atonic rocks Ben Rin n es Granit e d ifferentiation of — original mag ma intermediate and b asic m odifications c ati with Cai n m G a it mas —Mica Di it orrel on r gor r n e s or e . Lat am h D er L prop yre ykes .

CHAPTER VII .

PE ROGRA H O F THE AREA T P Y ,

at' G a it s a d Di it s Ea i f iat d I u c L er r n e n or e . rl er ( ol e ) gneo s Ro ks — — Metamorphic Rocks of Sed imentary Orig in Effects of t ct M tam Con a e orphism .

C HAP ER VIII T .

The Old Red Sa d st a d i t n Midd n one gener l s ributio . le or — — — Orcad ian Series main mas ses outliers contemporaneous t Old Red Sa — i andesi e . Upper nd stone d istribution fos s l id c —s cti at S caat C ai ev en e e on r g, Vi CONTENTS

HAP E R IX AGE . C T . P

GLAC AL AND RECEN D E OS S I T P IT ,

Di cti of i ci a ic -m m ts E atic c s—of re on pr n p l e ove en . rr blo k w t — — ca es ern area northern area east of the Spey . Lo l - d is e si of Di it B u d c a . Pre acia p r on or e bou ld ers . o l er l y gl l V - a e of Allt A d ia S a d s and G a s . ll y r er . Flu vio glac l n r vel

G acia a s . M ai i a u ia d sits . Basi l l L ke or nes . R ver ll v l epo n

P at . Hi P at e ll e .

C HAPTER X .

ECONOM C PROD C S I U T ,

— - im st s ana s s of R ad s Hi hwa s and R ad m tal . L e one ly e . o , g y , o e

- - - Bui d i st . Roofin s at B ic c a Mi a w ls . l ng one g l e. r k l y, ner l el I ronstone .

A PPEN DIX .

Pa t I Pa ae t ica —N t s on the F ssi Fi h an d P a ts r . l on olog l o e o l s es l n of the Old Red -Sa d st of Sc t a d n one o l n ,

I ist f Pa s refe i to th f t i Part I . L o per rr ng e Geology O he Reg on u d d sc i ti n er e r p on,

ist of M ic sc ic S cti s ar d f m R c s Part III . L ro op e on prep e ro o k c ct d in Sh t 8 5 olle e ee ,

LIST OF ILLUSTRATIONS .

PLA E I . E a th Pi a Allt D a F cha s Frontis iece. T r ll r, e rg , o ber , p

II Pre- acia Va Allt A d K oc a d F u i . gl l lley, r er, n k n o ; l v o acia Sa d s and G a ls sti B u d - c a gl l n r ve re ng on o l er l y, III Sa d s an d Gra s stin on Red B ul d -c a C iff . n vel re g o er l y, l a Ri S O sit R th s bove ver pey, ppo e o e , i l C d d h b d fi d with uartz ua tz -di it F g . . orro e orn len e lle Q Q r or e N etherl Bu of R thes E i y, rn o , lg n, a - wth of ua t z an d c di it C d ie it 2. Gr phic inter gro q r or er e ; or r e h f s N etherl Bu of R th s El i 52 orn el ; y, rn o e , g n, ' - 3 . Chia in chiast it S at Ard w I nn Banfishire 55 stolite ol e l e 5 ell , , EXPLANATI N OF HE T 85 O S E .

H TER I C AF .

— AREA EMBRACED IN THE MAR The district represented in Sheet 8 5 Of the Geological Survey Map Of S cotland includes an area of 432 ua ua the u t O f sq re miles , almost eq lly divided between co n ies

E and B ff of the S . lgin an , which lie on either side river pey C a - oi - A u ma a c t of h rleston berlo r y be reg rded as the en re the map, which extends in the north from Newmill westwards to the village Of R ff and u f B H a ord, in the so th rom the lack ill near the Lower

Cabrach to Dalliefure on the Spey . — FORM OF THE GROUND The highest ground in the area is found in u and u - c rf Of u f the so th so th west, when e the su ace the co ntry alls

northwards to the Shores of the M oray Firth. The dominant feature Of the district is the granite mass of Ben

R a d the Convals . i of Ben R innes n The long r dge innes, crowned t - a a as s currans Gaelic s oran s s wi h rock m sses loc lly known ( g ), ri e u to Of 2 55 f its a x t and grad ally a height 7 eet at e stern e tremi y, from its is olated position forms a well -known landmark over a vast

x t Of c un . A t a Of t u e ent o try no her tr ct high ground, wi h s mmits n f 1 500 2000 f a a the u rangi g rom to over eet, borders the re in so th , and ex tends westwards from the hills Of the Glen Fiddich Forest to the northern Spurs of the Cromdale range which divides the Avon A i f Valley from Strathspey. third h lly region O lower elevation f S and x far orms the watershed between the pey Lossie, and e tends to the north - eas t in a w ide expanse Of rolling moorland with a mean a of 1 000 f f ua elev tion over eet, that alls grad lly northwards to the a of f a a cultivated lowl nds the Laigh o Moray. Sep r ted from this

a au of S . and uc t high pl te by the valleys the pey Lossie , are s h isola ed as ua of Ben A a C i eminences the q rtzite peak ig n, above ra gellachie — 1 544 feet ; and the long ridges Of Eildon Hill and the Hil l of Wan i e f u the g , which rise with steep aces to the so th above the f an valleys O the Lossie d the Black Burn. The country between the Deveron and Isla and to the north and north-west of Keith is u l t ndulating, and broken into low hills and val eys. The smoo h rounded hilltops are clothed with wood or heather, while the slopes - u and valley bottoms are entirely nder cultivation. — - RIVER SYSTEMS The chief drainage system is that Of the Spey and its f - of u tributaries, ully two thirds the area being incl ded A 2 Exp lanation of Sheet 8 5.

of Of within the basin that river, which crosses the centre the sheet f u - B li rom so th west to north . On the right bank it receives at al n d alloch u A m its most important trib tary, the von, a s all portion Of r f h t ma only whose cou se alls wit in his p, and lower down it is Fid di h On f joined by the c at Craigellachie . the le t bank there ‘ are man affluents u Bu Allt y smaller , such as the T lchan rn, the Gheallaidh s Off of , and other stream flowing the southern slopes the El inshire -W of the a g moorlands . The north est portion are is n and the drai ed by the river Lossie, the eastern borders by the Isla D everon .

A ES — D NOir l of L K Loch allas, Loch , and other smaller poo s , all which occupy Shallow hollows in the drift-covered moorlands round a of Of the head w ters the Lossie, are the only natural pieces water in the map . Many Of the depressions in the sheet of gravel that ex tends to the north and south Of Rafford were also at one time a occupied by small shallow loch ns . These have now disappeared , either through drainage Operations or by natural silting up and

r n . vegetable g owth filli g their beds L. W R e 3 Geological Features and Surface eli f .

CHAPTER II.

l Geological Features and S urface Re ief .

An examination Of the map will at once Show the influence of the geological structure on the features of the country . The hills and higher ridges in the south and south - east have been determined the Of the a t and f the by outcrop harder qu rtzi e masses, ollow direction of their strike ; while the valleys have been excavated along the bands of softer slates and phyllites Of the Banffshire

serIes . The central granite protrusion gives rise at once to the most prominent features and to the highest mountain in the district ; the f a Of Ben R f Of C onvals lo ty pe k innes, the rounded orms the two , and the ridge Of the Hunt Hill on the north side of the Spey being

d ue to the unequal wasting Of this mas s Of igneous rock . The high - level moorland plateau between the Spey and the Lossie is f m f u - fl or ed rom the q artzo micaceous schist and agstone series , and owes its smooth contours and more or less featureless character t o he a a t and ua at n f t comp r tive homogenei y eq l we heri g o these rocks . The chain of hills that runs northwards from Craig an Tarmachain on the south edge Of the sheet to Cragganmore is a higher part Of t u a a of A this pla ea , isol ted by the deep v lleys the von and the Ben A a t f Spey . ig n is ano her isolated eminence ormed by an outlying s Of t ur u f the ma s hard quartzi e s ro nded by so ter rocks, while to incoherent conglomerates and soft sandstones along the northern border are d ue the fertile lowlands that descend to the seaboard of a Mor y . The only promin ent feature d ue to faultin g is the straight ~ trench- like hollow that extends from Dufftown past Rothes nearly to the edge Of the sheet . It coincides with a dislocation running

E. N .N .W . and SS E. with a downthrow to the , and has defined l of Fiddi ch Of the lower val ey the , the course the Spey between C and R Of R u raigellachie othes, and the deep glen othes thro gh which E now passes the railway to lgin. The elements Of surface- relief due to glacial action are chiefly of a u u Of those cc m lation rather than erosion. The original features Of the surface are to a large ex tent softened and modified by the f i dri t deposits which lie thickly in the valleys, swathe the h llsides, 0013 f and sweep over the , leaving only the higher hilltops bare o

u fi . E a s per cial covering rosive action may, on the other h nd, be traced in the rocky faces that are occasionally found low down the Of C of C on sides the wider river valleys, as at the raigs allander,

u at Culfoichmore S . at T lchan , and , in trathspey These may be 4 Explanation of Sheet 85.

ascribed to the action Of the later valley glaciers, which have swept ’ h out the deposits Of an earlier ice sheet from the bottom of t e

ar of . valley, leaving b e the projecting parts the lower hill slopes It is noticeable that these rock- surfaces are most frequent where the hillsides are steep and there is a certain amount of constriction in the valley—that is at the points where the ice would exert the f greatest abrading orce. Many Of the smaller tributary valleys have been completely t u filled with glacial deposits , hro gh which the present stream is now x Of rf -filled cutting a new channel . An excellent e ample such a d i t - a Allt A of Ballind alloch pre glaci l valley is seen along the rder, north see C ( hap . The drainage system of a country composed Of intensely plicated metamorphic rocks such as occupy the western portion Of this area x x a may be e pected to be a comple one , in which the l ws which govern the flow of streams through comparatively homogeneous u t and ndisturbed strata will be considerably modified. We here fore find that the valley of the Upper Spey is to a large ex tent u Of and a of inconseq ent, that is , independent the strike inclin tion the rocks through which it passes . The lower course Of the Avon for a a x a a is, on the other hand, long distance ppro im tely p rallel to Of the strike the rocks , and has probably been determined by the

‘ outcrop Of a band of felspathic fiagstones softer in nature than the more siliceous strata that form the hills on either side O f the river vallel Fui'ther anomalies fo und in the east and south -east parts Of the dis trict are d ue to the fact that the present drainage system is in im u u f Of t Of Old part a super posed one, and ca sed by an pli t s rata Red Sandstone age; These rocks may at one time have covered

b ut a d enud ation fi nearly the whole area, h ve since been removed by except along the northern margin of the sheet . ’ The position Of certain outlying fragments of this once wide spread covering affords direct evidence that many oi the river Of -Old -Red -S e a valleys are pre andstone age, and w re origin lly determined by the nature and distribution of the various members Pa Of and of the metamorphic series . tches sandstone conglomerate occur at several points along the courses Of the river Lossie and Bu a Of the Black rn, between whose par llel valleys the ridge schistose rocks that forms the Hill Of the Wangle rises to a height

- - Of 400 600 feet above the present valley level . Another striking f u the Of a instance is o nd on headwaters the river Isla, ne r the - of u f ut Of . farm Upper Towie, abo t our miles so h west Keith The stream here flows for some distance over a floor Of conglomerate which fills up the bottom of a deep valley excavated in the black of u s schist. The small patch conglomerate pon which re t the piers Of th e railway viaduct that crosses the Fiddich near Dufftown is again the last relic Of a mass Of Old Red Sandstone that at one time filled the valley Of that river. Similar evidence as to the age of the valley Of the Tervie Burn is afforded by the small area Of a n C th conglomer te seen alo g the stream side at raighead, close to e f ma has southern margin o the p. This valley also been carved and Sur ace Relie 5 Geological Features f f . out of the softer rocks of the Banffshire series between two ridges Of u Of of q artzite, which that on the north side rises to a height

1 000 feet above the bottom of the valley. Deveron Fid dich Du a i The , , llan W ter, and Isla, that dra n the ' u Banfishire u t area occ pied by the series , were th s at one ime con sequent streams as regards this covering Oi Old Red Sandstone that f Of dipped towards the north . They now ollow the strike the and are u u u underlying schists, th s s bseq ent with respect to the f Their resent t rocksthatform thepresent surface o the country. p nor h east course is probably a modification of the superinduced northerly u n f u d ue u a course, and was prod ced when the origi al eat res to nequ l hardness Of the metamorphic rocks reasserted themselves as the overlying strata were removed. To this cau se may be attributed the remarkable deviation in the u Of Fid d ich Cold home co rse the at , where the river bends u u a Duff an s ddenly ro nd and flows westw rds to town, making angle ° O f less than 60 with its track above the bend . The ridge between Carron Hill and the Tip s Of Corsemaul now f a s t Fid dich the a and orms the w ter hed be ween the and Isl , rises But nearly feet above the valley of the former stream . at the time when ridge and valley were alik e concealed beneath the Of Old Red Sa a a u Of covering ndstone str t , the pper waters the Fid dich wou ld naturally fiow northward across the present water f Of shed into the valley O the Isla. In the process time the sand stones covering the ridge Of metamorphic rocks were gradually u a and fi it removed by den d tion, the stream, nding easier to erode the softer rocks that still filled up the Dufftown valley than to cut u Of and u u u thro gh the ridge schist q artzite, t rned to the west, th s robbing the Isla Of its headwaters and Swelling the volume of a smaller stream that must already have been cutting back out of the f f u - Dufft head O the a lt determined valley below own . A similar course of events s eems to have determined the courses Of the river Lossie and the Black Burn in the north -west portion of this area. Prior to the removal of the general covering of sandstone from a a as a t this region the Lossie flowed se w rd consequent stream , wi h the same northerly trend that it still retains in the u pper part of its course above Dallas . It was joined by the Black Burn on the Of H of Mulund west side the ill y, and the combined streams, passing northwards through the well-marked hollow through which now u R ff f Findhorn r ns the road to a ord, ell into the river somewhere t Of F A near the presen site orres . s the sandstone covering was a u m a gr d ally re oved by the wasting process, the earlier topogr phical f s u eature would again come into play ; and the Lossie, t rned aside by the ridge Of metamorphic rocks that runs eastw ards from the H of M ul und a ill y, eroded the softer strat that still occupied the w hollow and returned to the ancient river valley belo Dallas. The watershed between Rafford and Briach Mill is only abou t twenty feet above the present level of the Black Burn at the latter u locality. It is th s probable that this stream retained its northerly u F F a co rse to the indhorn to a considerably later period. in lly f u however, the influence of the original s urface eatures, co pled as in the case of the Lossie with the cutting-back of a stream in the Of the B a valley to the east, produced the present deviation l ck B a urn e stwards under the Eildon Hill. of S t f the The present channel the Lower pey, apar rom valley — r l. O t th ough which it flows, is largely post g lacia ver the grea er of s e part its course through thi sheet, and especially betw en Ballindall och C n and arron, it is flowi g over rock and still deepening its bed, while the mass Of fluvial and glacial deposits that still remains in the principal and tributary valleys shows how deeply it has -fi S f trenched the waste lled basin since glacial times. The wi t of its ness lower course, which is abnormal in comparison with Of ff Of the gradient its middle section, is probably the e ect an uplift along an axis that crosses the river considerably further up and of a of the valley, is later date th n the erosion the higher of portions its course . S The pey may thus be regarded as a compound river, made up of t n Of ff a e and of two sec io s di erent g , at unequal stages erosion while the portion which falls within the region under des cription has nat ft ik s in been rejuve ed by upli , and, l e many other stream the

ff x m Of u . area, a ords an e a ple s perinduced drainage A well- marked constriction of the Spey Valley occurs at

Aik enwa C 1 N.N.E. of R . At y astle, }1 miles othes this point the quartzite of Ben Aigan at one time formed a rock-barrier which dammed back the waters of the Spey over what is now the fertile H Of R h augh ot es, and was possibly high enough to divert the course of the river north -westwards through the Glen of

Rothes . Indications of this former course of the Spey are found in - e b e the high level terraces that flank that gl n, and can traced s outhwards into the river terraces between Rothes and Kn ockando

see . H. ( Chap. L. W

Geological Structure in Relation to Pop ulation and Economics.

A close connection exists between t he geological structure and the distribution Of the population Of the country represented in this u and t map . This relation between struct re popula ion only holds for 1 000 f for at good, however, ground below eet above sea level, higher elevations grain and green crops cannot be profitably

Of S . Ou e the of cultivated in this part cotland tsid burghs Keith, Duff R l a Of A Newmill Ar town, othes, and the vil ges berlour, , chies D e e l lOCal town, and allas, which are more or less ngag d in smal n s r n rt of S is l l i du t ies, the remaini g po ion the heet either agricu tura ,

s l . pa tora , or moorland The firs t factor which has determin ed the dis tribution of the agricul tural population appears to be the geographical pos ition of the ri u fluvio- a va o s alluvial haughs, terraces, and glaci l gravels ‘ Of B B r e which are distributed along the valleys the lack u n, the riv rs e S A D l e Fiddich Deveron Lossi , pey, von, u lan Wat r, , Isla, , and their various tributaries . It was on these terraces and lower valley slopes that the Geological Structure in Relation to Pop ulation and Economics . 7

fa f the agricultural population first settled in rms and cro ts , while l further ex tension Of agriculture and population higher up the hil slopes and across the areas which separated one valley from another was chiefly determined by the nature of the intervening rock zones . There is also an intimate connection between the size Of the farms and the extent Of the alluvial deposits at any one F S point . rom Dand aleith to Dipple the river pey has deposited u are the largest ha ghs and terraces in this sheet, and on these

situated the largest farms in the map . The decomposition of the granulitic flagstones and schistose grits for a produces a poor, damp soil, which is neither adapted rable nor a u and fla stones a p storal p rposes . These grits g are gener lly u f- covered by t r peat and heather, while deep p eat mosses occupy h u find the Of S and t e hollows . We th s that on west side the pey on either side of the river Avon the ground over which this series ex tends is chiefly utilised as grouse moors with a few scattered u a of t t Of i s grazings, while the pop l tion his por ion the country almost entirely confined to the alluvial haughs and terraces which

intersect it. M Old Red Sa x f The iddle ndstone series , which e tends rom the G H ll the of a c allows i to river Lossie, is entirely composed oarse As i u conglomerate with a thin covering Of gravelly soil . th s gro nd for Of a a of is very suitable the growing timber, l rge portion this a has and u a rea been planted, in conseq ence there is a very sc ttered T in land and a Thomshill population . On the e d round the con glomerate is covered with a considerable thickness of sharp gravelly f f Of dri t. This deposit is largely derived rom the denudation the ” Upper Old Red and Triassic Sandstones of the Laigh of Moray and was laid down over this part of the country by the Moray w Of Firth ice sheet . The hole this area along with the small portion Of Upper Old Red Sandstone at Longmorn is well cultivated fu u u and maintains a ll agricult ral pop lation . From the east Side Of the Spey to the margin Of the sheet thos e a Of ma u i - s are s the p which are occ p ed by the phyllites , black schi t ,

and s are u u 1 000 f . lime tone, generally well c ltivated p to eet Su f f ri f aff a the r ace dri t de ved rom these rocks ords clayey soil , of a ff x lower part which is generally sti till, and where this is mi ed with the peat in the valley bott oms a clayey loam is produced up n a u to 1 000 feet. A gric ltural population is pretty evenly distributed in crofts and small to medium sized farms all over that portion Of the map occupied by these three members Of the ’ Banflshire x of u series, with the e ception that part which is incl ded Fid di h A within the Glen c deer forest. bove the limit of culti vation over these three zones the ground is either pastoral or else a a a pl nted with timber, with very sp rse population . From Ben Aigan to the Black Hill of Corinacy many of the hill ' Banfishire tops and ridges are occupied by the quartzite , a hard Ma of siliceous rock which does not readily produce soil . ny these hills carry no soil and are frequently covered with their own debris - a overlaid with turf peat and he ther . When soil covers these “ quartzite areas it is Similar to that produced by the Cromdale 8 Exp lanation of Sheet 85.

H a for ills series, and as it is poorly ad pted cultivation there is almost no population where quartzite forms the rock of the An ul country. exception to this absence of pop ation over a quartzite area is found at the foot of Glen Markie and around the Bur of Edin l i n g ass e. These two small valleys have a thick covering of drift chiefly derived from thephylli tes and black schists

W f . which are in place to the S W. o them This is another instance within the sheet where the character Of the glacial deposits and not the solid rock beneath has influenced the distribution of the l . S . G. . popu ation J . W

1 0 Explanation of Sheet 85.

General Geological Structure of the Area.

The ground east of the river Spey is chiefly occupied by the Of B ff Of rocks the an shire series , the various members which are arranged in a succession Of roughly parallel bands across the sou th a of G Tervie Of Ben e stern portion the map between len , south

R . u innes, and Keith These q artzites, schists, and limestones represent a portion Of the belt Of more or less altered sedimentary rocks with associated igneous intrusions which ex tends almost — continuously across Scotland from the south west of Argyllshire to M F the oray irth . They are particularly well developed in the adjoining Sheet to the south and have been described in the x a t s e pl nation accompanying tha heet . The granulitic schistose rocks of the Central Highland or Moine schist type cover almost the entire western half of the " map . The more siliceous portions Of this group have been coloured t f of yellow on the map , but are dis inguished rom the quartzites the Banffshire series by the addition Of the letter in to the index S ymbol x. The quartz schists and flagstones form the western Slopes Of Ben R C H and innes, the romdale ills, the high ground that rises to the north - west of the Spey between Allt Arder and Delliefur while the wide moorlands that stretch northwards from the watershed to the head wate rs of the Lossie are occupied by the undifferentiated a of u schists and gneisses of this series . The sep ration the vario s rock - types in this latter area is rendered difficult and indeed Often impossible by the great ex tent and thickness Of the peat and drift ‘ with which the hills are covered and the consequent absence Of rock For sections . the same reason the line drawn on the map between Si these rocks and the more liceous group in the south, is a very conjectural one . A considerable area of conglomerate and sandstone occupies the S ground on either side Of the pey north Of Rothes. These f are u sediments rest uncon ormably upon the schists, and pres mably M Old R d S of Orcadian or iddle e andstone age . TO the north Of the Glen of Rothes and along the margin of the map these are in their turn covered unconformably by sandstones belonging to the U Old Red S Of pper andstone period, while smaller patches these u D Pluscard en R ff latter rocks also occ r at allas, , and a ord . The plutonic rocks are confined to the central and eastern of u and the portions the area nder description, almost entire absence of igneous masses in the Central Highland schists is a striking u f f of feat re o the western hal this sheet . The earlier intrusions ‘ are represented by the basic and ultra- basic sills associated with the Banffshire series and intruded into those rocks prior to the move e TO ments that produced their pres nt schistosity . the same period may be assigned the foliated granites or augen-gneiss that Of pierce the schists in the neighbourhood Keith . Later than the schistosity is the large mass Of unfoliated granite of S at A which disrupts the rocks on both sides the pey berlour, and l forms the mountain mass Of Ben Rinnes and the C ouva s . A more G r tu o the Are eneral Geological St uc re f a. basic phase Of this intrusion is probably represented diorite of u Hill Of Stob and Netherly On the B rn Of Rothes . A few lamprophyre dykes are found in the quartz schists Of Ben A a Of u ig n, and a bed contemporaneo s porphyry or andesite Old Red Sa Of the C t ie u occurs in the ndstone abrach ou l r, in the so th f east corner o the map . 1 2 Exp lanation of Sheet 8 5.

CHAPTER IV.

Metamorp hic Rocks .

QUARTZITE.

On the east side of the river Spey the metamorphic rocks have been thrown into a series Of isoclinal folds which have determined t heir arrangement over this area . It is more than probable there is only one zone Of quartzite ; the repetition Of the rock in a c u ax par llel bands and deta hed lentic lar masses, whose longer es

- - u d ue of f . lie north east and so th west, being to this system olding As a ua already indic ted, the q rtzite, owing to its greater hardness, a f and l the inv riably orms the hills ridges, whi e lower slopes and are of f ac and valleys carved out the so ter phyllites, bl k schists, a limestone . In this sheet there is no direct evidence th t the qu artzite rests unconformably on the other members of the Banff t for shire series . The indirec evidence is very strong, a glance at the m ap shows that the main belt of quartzite which stretches from the Glen Fid dich forest to Invermarkie is at variou s point s in

c c s . But u contact with phyllite , bla k s hi t, and limestone it sho ld u u a u S 85 be borne in mind that, thro gho t the are incl ded in heet , u the q artzite, phyllite , black schist, and limestone have been the affected by a common system Of folds . In character rock varies from a very fine- grained homogeneous crystalline-granular it rock to a hard massive granulitic quartzite . In colour a f t a t and finer- v ries rom grey whi e to dir y yellow, the grained ua varieties when freshly broken have a pinkish colour . The q rtzite hilltops Of this portion Of Banffshire are Often covered with its - a . O debris, which weathers with snow white colour ver the greater portion Of the northern half of the area this rock is felspathic and ranul itised and Of e u - f g , ten pass s into a q artzo elspathic schist with

white mica developed along the divisional planes, while towards the u - elastic a can so th east the original gr ins still be recognised, and in several localities bands of pebbly grit prove the sedimentary origin

of the rock . In proceeding to describe the variou s areas Of quartzite from - - north west to south east, the first in order is that which extends from near Craigellachie to the north of the Burn Of Mulben and f of Ben Ai 1 544 f M orms the hills gan ( eet), and Knock ore

(1 1 67 feet) . is f The quartzite throughout this area very uni orm in character,

massive and granulitic, with the bedding planes well defined . Numerous dips have been Observed in the streams which flow down Of Ben A n a e the western slopes iga , and these indic t a general m r h c Rocks 1 Meta o p i . 3

c - - For a u two in lination to north east and south west . bo t miles S of B Of B along the river pey north and south oat ridge, a hard,

u x . B Of M u massive , purple q artzite is e posed In the urn lben and north to the boundary of the Old Red Sandstone this rock is very u t the u u a a all m ch sha tered, and s bang l r brecci ted portions have been re-cemented together by a siliceous bas e into a homogeneous rock with occasional drusy cavities in which occur crystals of u u u Of x as far q artz or barytes . The p rple colo r the rock e tends u as Of c d ue Old so th the Woods Kno kmore, and is to staining by Bu of M u t t Red Sandstone . In the rn lben and wi hin a shor distance Of the eastern limit Of this area bands Of quartzite and

phyllite are folded together . At Sheriffhau h t s a a a g hi rock loses its brecci ted ch r cter, and the Allt Daley which flows into the river Spey at this point affords an almost continuous rock section to within a short distance of the top Of t a Of Of Ben Aigan. In the lower portion this section hin b nds m °— ° 1 2 S . a a a f 1 0 1 5 quartzit e inclined to E. t ngles v rying ro

a a h ua and fla s tones . Hi u the ltern te wit q rtz schist g gher p , dip is ut the ua t t as inclined more to the so h, q r zi e becomes more m sive, and a s s Of a a and the thicker h rder band give rise to a eries c sc des . a Of the c is as a and Tow rds the top hill the ro k occ ion lly brecciated, at the head of the section bands Of qu artzite are folded with the

- mica schist which occupies the ground to the east . The tops of Knock M ore and Ben Aigan are covered with angular of ua t fine debris pink , grey, and yellow q r zite with very dendritic

a n at n . On the a of S at m rki gs , we heri g white b nks the river pey Aikenway and below Arndilly House the rock is very much a and has c t a ia t a sh ttered, been onverted in o brecc wi h l rge and small subangular fragments cemented together in a siliceous matrix and stained pu rple by the recently removed Old Red Sandstone s Of t i a ma beds . The ea tern boundary h s rea is shown on the p by a c b ut d ue a of omparatively straight line, this is to the w nt h Of M u A exposures between t e Glen lben and Tanz ie. t the latter point a massive quartzite with black-schist above passes in below

- the mica schist to the east. The upper portion Of the burn which flows past Arn dilly House runs through a ravine with steep u cliffs of white and pink q artzite . TO the south of Rothes and on the east side of the wood Of onerock x u of u C there are several e pos res a very pec liar rock . It is a brecciated - looking complex Of vein quartz and quartzite in a siliceous matrix stained irregularly in strings and patches with “ ” heematite. C R Of a The one ock , at one time the site an ncient f u a f a of Hau s and ort, is sit ated in the wood h l mile to the west gh , Of t a is entirely composed his brecci ted rock . It is probably a f u a d ue Of ca C a lt brecci to the line dislo tion described in hapter II . It contains numerous drusy cavities of all Sizes lined wit h crystals Of u cut u fu q artz, and when and polished has a very bea ti l

appearance . B Duff H M Of etween town and erricks oss, north Keith, small isolated lenticular masses of quartzite occupy the tops O f several A Of u x of the hills. narrow belt white q artzite e tends along 14 e 5 Exp lanation of S he t 8 . the north -east bank of the river Fid dich on both sides Of Ki ninvie H u and u H C o se, in the branch b rn at azelwood ottage vertical beds Of the same rock are seen alternating with black - A of schist and mica schist. considerable area quartzite covers the Scau t Hill and ex tends to the north -east as far as the Lochend n Wood. O the roadside Opposite to Waulkmill the rock is much shattered by the fault which follows the valley of the river

Fid dich between the Mains Of Newton and Balvenie Castle . In a small stream to the north - east Of Little Tulloch the highly inclined u of beds are finely conglomeratic . The nat re the debris on the top Of this hill shows that the underlying rock is fine grained and in u places not m ch altered . The flat moor between the Knockan and M achatties Cairn is f f f an ree rom dri t d covered by white quartzite debris and heather . “ ” N of C orth the airn , in the small burn which passes down to Broad rashes a of - all , b nds quartzite, black schist, and phyllite,

a f . A inclined at high ngles, are seen olded together glance at the map shows that in the north -eastern portion Of this area the au quartzite is thrown into five sharp folds . In T chers Wood there x of of S are several e posures bands pink quartzite with yellow pots, ° inclined to the sou th -east at angles varying from 30 The rock which occupies the Moor of Auchanacie is a fine-grained light -brown foliated quartzite with ill - d efined patches of brown a u - staining. In many pl ces it passes into a q artz schist with white a a f f a A f mica developed long the pl nes o oli tion . similar rock orms the small lenticular mass at Blackhill Wood to the sou th - west of - Of - Keith . In the north east corner this sheet a wedge shaped area of quartzite stretches from Herricks Moss to within a short distance t Of of N ewmill . In the stream section to the sou h the moss the

25 S . rock is inclined to E. at comparatively low angles and consists of ua . x s Of hard , laminated, flaggy q rtzite The e ten ion this band to the south -west has been traced by means of numerous Shallow Of ai quarries and rock knobs. The western slope the C rds Wood Hill south of Keith is occupied by a lenticul ar area of very hard u t u Of ua A massive q artzite raversed by numero s veins q rtz . t D rummuir Station the groun d between the public road and the railway is covered by an oval shaped area Of very hard yellowish f - A quartzite surrounded by a belt o black schist . t the back Of the station this schist is seen passing in below the quartzite with a - l south easter y dip . South Of Dufftown the ridge of high ground which separates the of D Fid dich f . valleys the ullan Water and river is also ormed f u — of Pit las i O q artzite . To the south west g s e it is brecciated and l e' Of s o granulitic, whi crags white quartzite ri e to the south f Cairn

. B C Bell hack H more etween arron and y ills, in the Parish of Botri hnie the f p , no rock is seen in place, but sur ace is thickly u u covered with ang lar q artzite debris . The largest band Of quartzite enters this sheet in the Glen Fid dich Forest to the south Of the Hill Of Glenroad s and traverses the map - i in a north easterly d rection . This is the northern ex tension of the * area which lies on the west Side of Glen Suie in the sheet to the

E anation of Sheet 5 . 9 . xpl 7 , p 1 Metamorp hic Rocks. 5

u u south Its o tline is very irreg lar, and its breadth varies F u u of from 400 yards up to 3 miles . rom the so thern bo ndary id dich b ut the map to Glen F lodge very little rock is seen in place , its position is inferred from the quantity of quartzite debris which A ma w f of covers the hilltops . glance at the p sho s the olding the quartzite in Glen Fid dich between Tor Elick and the Hill of C nan Earb u a the Of lais , with the res lt th t same beds phyllites h F and limestone are repeated on both sides of these two ills . rom S Fid dich x the lodge to below mithstown , the river e poses a good of fla s u t section consisting grey, ggy, mas ive q artzite wi h mica

- schist partings inclined to the south east at various angles . To ’ the north-east of Laird s Seat grey phyllites pass in below this at u a rock, and Laggan, where the bo nd ry line crosses the river, a cliff of soft decomposing quartzite is in close proximity to the - of Sc H of black schists. To the north the alp ill this belt u t a of f u a q artzite is hrown into series olds, and its bo nd ry then turns to the south as far as Garb et Hil l at the head of Glen

Markie . That the beds of quartzite are often repeated by folding to the east of Glen Fid d ich is evident from the fact that between Cairn Crome and Ben M ain there are t hree small areas of phyllite and B limestone entirely surrounded by quartzite . etween the Meikle Balloch Hill and Burntreble the strike of the beds changes from and u and a t its normal direction to north so th , at the s me ime the a a of u Of f vertic l b nds q artzite are thrown into a series olds . The result of this plication is to carry the boun dary of the quartz ite f Ballochford Burntreble fa u rom to a point near rmho se, whence it a - a a as far as H l of Dum eath a has been tr ced north e stw rds the i l ,

distance of four miles . The road from D ufftown to the Cabrach passes to the south of ” M B H l u G the the eikle alloch il thro gh the lack, and at this point white quartzite is converted for some dis tance into a fault breccia composed of sharp angular fragments of quartzite of various d imen

- sions embedded in a siliceou s felspathic matrix . The angul ar debris and occasional exposures of rock seen on the high ground to the east of Glenmarkie indicate that the ridge that x a f Garbet H Ga H e tends northw rds rom ill to llow ill, and the upper of a of the are c u t b ut part the e stern slopes glen, o c pied by quartzi e, the position of the boun dary line between this rock and the black schist is obscured by the almost uniform covering of peat and - u t heather. Thick bedded q artzites firs appear in the stream section

f N . t an B o M a E . 28 a d f below urnside rkie, where they dip rom this point to the M ill of Invermarkie bands of quartzite alternate and of f T f with black schist thin sills oliated diorite . o the north o of u c t a this section the bands q artzite be ome ver ic l , and this rock covers the whole of the Tips of Corsemaul as far as Bodylair and B a h the Crofts. etween these two loc lities and t e hill of Dumeath f uartz ite divid es B this zone o q into two separate belts . oth of these 8 6 Blacklu pass into sheet , the northern one at g, and the other at in n n the Wood of Strait na . O the east side of Glen Fidd ich the Scaut Hill is covered with a very fine-grained crystalline granulitic 1 6 Explanation of Sheet 8 5.

u u yellowish q artzite . A local base to the q artzite is indicated a by the co rse pebbly grit, almost a conglomerate , that occurs on

- the ridge of the Black Hill in the south east corner of the map . u a ul The rock is not act ally seen in pl ce, but the large ang ar masses which protrude in profusion through the peat that covers the hill top indicate its presence below . The well rounded pebbles are some times as much as 4 or 5 inches in diameter and are chiefly composed

Of u u . white q artzite , s ggesting that this rock is due to local erosion Its local character is also shown by the fact that less t han a mile ' - to the eas t it passes along the strike into qu artz schist . To the north of this hill a narrow and much folded belt of grey and white quartzite forms the division between the black schist and phyllites . The small lenticular band which stretches frOm Bridgend in the a of Bu s Of D everon m H v lley rn Treble, we t the , to the Kel an ill is f a s of a grey oli ted schistose grit . It lies on the ame line strike and f f B of is evidently an in old o the Blackwater beds . elow the Mill Lyneburn on the Deveron thin bands of a similar schistose grit are

f u a . J S . . o nd associ ted with the black schist . G W.

LIMESTONE.

The main ou tcrop of limestone in the area east of the Spey ex tends in a narrow and almost continuous belt from the head of Glen Tervie through Glen Rinnes and along the D ullan Water to Dufftown ; and thence by Loch Park and the valley of the Isla to On t of u Keith . bo h sides this belt there are numero s small isolated bands and small lenticular areas of limestone which are associated n out either with the black schists or with the phyllites . The mai a d ue crop varies consider bly in breadth, this variation being partly c u a t to the onditions nder which the limestone was origin lly deposi ed, and partly to the intense overfolding to which it has subsequently A f th Ba ff been subjected. description o e n shire limestone is given x 75 out in the e planation to sheet , in which it is pointed how a d n of ma u n small ban , origi ally no great thickness, y thro gh repetitio f u x of u by olding be made to occ py a very large e tent gro nd . The limestones which are wrought or burnt for lime throughout this district are very uniform in character ; they are highly f c u crystalline, and vary rom light to blue grey in olo r. They often Show distinct bedding- planes and bands of light and dark grey

schist . In some localities this rock has been brecciated and e- t l r cemented toge her by calcite, whi e in other places the bedded i Of l mestone is traversed by large veins and eyes pink calcite. The u a u t less p re bands are generally d rk , m ch hinner, weather with a u f rusty brown colo r, and are o ten associated with black schists . N0 contact minerals have been Observed in the main outcrop of this in x m Ben R a b ut rock where it is close pro i ity to the innes gr nite, i a d ue v u the r bsence may be to the comparati e p rity of the limestone . At of G R N Auchmor the head len innes, below ether e, several strong spri ngs locally known as the Lagantoul Wells flow from u the limestone . In a neighbo ring quarry the rock is a grey saccha oid al a o r bedded limestone tr versed by veins f calcite. From this

1 8 Exp lanation of Sheet 8 5.

sid erabl u Drummuir Limew rks, e plication. Here were sit ated the o but the quarry was abandoned about six years ago when the lu ne stone to the north became exhausted. At Poolside the beds which form the edge of this zone are the x s of only ones e posed, and consi t calcareous schists dipping below — Millcroft the n black schists . Limestone appears at , and in bur to the north of C oldhome an outcrop indicates the position of this zone as far ua r has in re as the lim ework at Braehead. This q r y been opened a g y - crystallin e limestone with thick partings of black schis t. A s hort dis tance to the south of it there are two infolds of dark limes tone in r s s s and calcareous schist. Almos t at the po t whe e thi zone pas e out of e -f e r i is all e i the she t at the SOD e t contou l ne , there a sm op n ng n — s in a bed of blue crystallin e limestone dippi g to the south ea t . Another small infold of a similar rock occupies the bottom of the valley of the river Isla from near Blackhill Wood to the east of F f - At f Maisle i e Keith . the ormer point are situated the y, and on the of Dou lasbrae Limeworks opposite bank the river the g , both of In e of rri tac which are now abandoned. ach the qua es at hed to these works light grey crystalline limes tone veined with calcite - - d the a . i r l i c ips to south e st Th s is in tu n over a d by bla k schist, and a simil ar section is exposed in the railway cutting eas t of Fife

Keith. Isolated areas of limestone due to small infolds with the black One of e s chist are found on both sides of the main outcrop . thes occurs two mil es to the west of Fife -Keith and close to the Mulben x u of r s l i road, where there is a good e pos re a grey c y ta l ne bedded l m s i i estone about twenty feet thick . Thi band is also seen cross ng Rosarie B d n r the to the the urn . Another isolated ban e te s sheet

“ ‘ south of Keith and is quarried at the Blackhill ock Limeworks . The 40 f and the e a workable rock is about eet thick, b ds are ne rly A n C s in G n horiz ontal . The grey limestone at uchindow a tle le Fid dich f a u 250 fe and l orms a craggy slope bo t et high, a simi ar s the of Earnfold rock occur on same line strike near , where it is f ae very much brecciated with small veins o h matite. The band which crops out in Glenmarkie below Belnab oyle is highly contorted

- f . x and olded It is a poor grey white sandy limestone, but in pro imit y to the diorite it becomes much purer, and is almost converted A Fid d into marble. small band enters the map in the Glen icli f e t l l as of H of or s , whi e the smal lenticular are on both sides the ill E r ar s t f ds of th Clais nan a b e doubtless i ola ed in ol e same.

. G. . J S. W

- BLACK SCIIIST.

The larges t area of black-schis t in this map lies between D ff x h of u town and Keith, and e tends westwards to t e centre the s of B Pari h oharm. The general character of these rocks is that of s e a dark carbonaceous schi t with some slat bands . The amount of carbonaceous material present in the rock constantly varies ; it is a l d n n e s s o in gener l y more abun ant in the regio me tioned abov , le s the en a and rea es in - c tr l area inc s again the belt to the south eas t. 1 9 Metamorp hic Rocks .

of r u u Its rate decrease is also very i reg lar , a very dark bl e schist passing in a very short distance along the line of strike into a " phyllite or mica-schist by the dis appearance of the carbonaceous material . Where these schists have a blue -black colour they are often a distinctly graphitic . In many inst nces the original bedding can i a a planes be recogn sed, especi lly in the less met morphosed a b ut s are f u f sl tes, the e o ten obliterated by the s bsequent oliation and the strain- slip-cleavage which has produced the corrugated structu re s o prominent a feature in the more schistose varieties . a a un a t Garnets are toler bly b d nt in hese schists in certain localities , and there is als o a sporadic development of secondary minerals such

a and aur . f u as actinolite , kyanite, ndalusite , st olite The more req ent occurrence of these accessory minerals in the neighbourhood of the Ben R n and a of B a i nes granite, the g bbros and diorites the lackw ter

- Deveron su ests . One of and river , gg their thermo metamorphic origin the best sections in this district is that afforded by the burn and u a c Fiddich M a s of N u its trib t ries whi h joins the at in ewton , abo t F f t of a mile and a half to the east of Craigellachie . rom the oo this burn to the M ulben road the section displayed is entirely of f and c u a c a - ac composed so t, twisted, orr g ted o l bl k schists with

i a of . are a th n b nds limestone These beds strongly gr phitic, and in two of the small streams above the bridge they contain a con sid erable a of a a w fi qu ntity iron pyrites , while sever l b nds sho nely a of a u At developed cryst ls ctinolite p to four inches in length . the foot of the small burn below Dinnyhorn black-schists with thin bands of limestone dipping north -east and south- eas t are succeeded by phyllites with strains and partings of black - schist and thin a i i f d of limes tones . The r p d nter ol ing the beds in this section results in the frequent repetition of the same bands. In the section at Knockan and in the two small burns immediately to a f an d w u of the north simil r olding is seen, bet een the q artzite Machatties Cairn and the phyllites of Mu lben a comparatively thin portion of this zone is in this way made to occupy a considerable As a of Auchlunkart H u a a area. these schists e st o se ppro ch the f a of Muld erie H c a f u oli ted granite ill they be ome g rneti ero s, and a a s of a- A o altern te with b nd mic schist . very good section f these t u f f a a schists, wi h min te puckering and olding along the oli tion pl nes, a is displ yed in the burn to the west of Cabb achs . From the line of fault north of Craigellachie north to Auchlunkart the western u of s fi a of m bo ndary thi zone is well de ned, and in m ny the s all streams intersected by this divisional line the phyll ites are seen a - dipping in below the bl ck schists. The small burn that joins the river Fiddich immediately to the north of the Farm of Tulloch flows over dark schists full of iron

' r t of py ites, and he decomposition this mineral gives rise to a thin effiorescent of um of coating al on the rocky sides the ravine, while the water which trickles over the rocks is strongly impregnated

. S u of Balvenie C f a of with the same salt o th astle, on the le t b nk Fid dich fine a the river , there is a very section showing vertic l and of - u of t s highly inclined bands black schist, which at the pper end hi 20 Exp lanation of Sheet 85.

’ In the rock exposure are interfolded with the Dufitown limestone. ‘ Auchanhand ock u - of Dufitown stream below , so th east , and also at f of - ar f u lites its oot, bands black schist e o nd in contact with phyl , but from the latter point to near Drummuir the line between this zone and the mica-schists is rather in definite on accoun t of the e of ex absenc rock posures . Drummuir C l in at Tenatown In the ast e burn and also that , black-schists with some thin quartzose bands are folded with thin of ul u beds blue crystallin e limestone. The triang ar area aro nd St arhead - of Drumm uir S ff m , north east tation, a ords nu erous ex of i n posures this sch st, and in the small stream which joi s the B of Davids t on the of Howd ou e are urn to east p the b ds very dark,

u . l ex carbonaceous, and finely corr gated The al uvial flat which tends eastwards from Mul ben to N ew mill forms the northern boundary of n il f - A this zone to withi a m e rom Fife Keith . t this point the boun dary line folds back upon itself for some distance and thence - u t . C s wn contin es wi h a north east course towards Keith lose to thi to , u of B i r at the old limestone q arry raehead, this sch st is ve y much w and Blackhill ock u i t isted, at and aro nd the Ca rds Wood it is very f t i At th dark and o ten con ains much graph te. e southern margin of the map similar rocks occupy the col between t he Tervie and Favat burns and ex tend northwards into Glen Rinnes as far as

Su . of Balmerion ccoth In the burn they are very black, with

n J . S . G. . i tercalated bands of limestone. W C - s are x orrugated black schi ts, more or less graphitic, well e posed ur of Tervie r Tomachlaven along the b n , whose cou se between and f M ains of M orin sh is parallel to the strike o the rocks . With them u u n u f La avaich are intercalated n mero s thi calcareo s bands , and rom g of ur u - a broad band p e and highly crystallised bl e grey limestone , n f and f of i tensely olded contorted, ollows the course the stream to x of the the edge of the sheet. The e posures seen near the head Tervie Burn and in the small stream immediately south of Black t is a ut knowe, show hat as these sch ts pproach the so hern boundary of the Glen Rinnes granite they become garnetiferous and also ur t u develop large and perfect crystals of sta oli e and andal site . The relation of these crystals t o the puckering of the schist proves that they were formed subsequently to the movements which produced

scliva e. . . t he puckering or ausweichung g L W H. — - The central black schist area ex tends in a north east direction from near Auchindown Castle to Corsemaul and crosses the Hill of ' M ackalea into Glen M arla c ; the ex tremely irregul ar course represented by its outcrop being d ue to the rapid folding of the ’ Au w C u clifi f of beds . chin do n astle stands pon a ormed vertical of l n e im in the i beds blue crystal i l estone, and rav ne below, on both of a of - i the sides this crag, b nds black sch st are seen dipping towards The e 6 limestone. schists her and also at a point 00 yards lower Fiddich in k down the are spotted and conta small nots. The hill ur n Fiddich the e b n which joi s the river below castl , gives a continuous rock exposure in which the beds have a general inclin - t the of the n ation to the south eas , upper portion sectio bein composed of slaty bands which are seen to pas s below the yellow c s 21 Motamooj ohic Ro k .

u t Due f m irn q ar zite that caps the top of the hill. west ro the ca on the Scalp Hill and about three hundred yards below the edge of the quartzite a considerable quarry has been opened in one of the slate a i l bands . These slates show origin l bedd ng planes, are very bad y

of ur of s . u cleaved, and partake more the nat e a flag tone This q arry is n - of the H of now abandoned. O the north west shoulder ill M ackal ea b ut the the same band has been recently opened out,

ua of di ff . At orsemaul Raehutcheon q lity the slat e is very in erent C , , Earnfold i u a of and , th n lentic lar b nds dark grey limestone are a G M - ssociated with these schists . In len arkie this black schist , t u together with the dark impure limes one, is traversed by numero s sills of basic rock which have produced a certain amount of contact a lteration in the schist . At the head of the Corryhabbie Burn there is a considerable area of - very dark black schist with slate bands . The beds are inclined to the south-east and pass below the quartzite which lies between l h At F of Corr habbie a this glen and G en Fid dic . the olds y and long in of r s f as t their l e st ike, these bed are inter olded with and p s in o fla l A cul of r grey ggy phy lites. small lenti ar belt g ey and black slates with crumpled graphitic bands extends along the east side of G Fid di h A len c and passes into the sheet to the south. nother band of black-schi st crosses the south -east corner of the sheet from A u t a r A rdwell to S cco hbeg in the v lley of the Deve on. t Lower Ardwell in the river section and alongside the turnpike road there x of are e posures slates with knots and crystals of andalusite . This a of Deveron b nd crosses to the east side the river , and towards the top of the Hillock of Echt burn very hard black-schists are seen in a s passing to grey knotted and andalusite schis ts. In the stre m a Succothbe M - G t a round g and eikle ouls the schists are ver ic l , very

a a u of . B bl ck, and contain a consider ble q antity graphite elow Beld ornie Castle the river has cut a deep gorge through crumpled and contorted black-schists which show a considerable amoun t of - a x of contact met morphism, doubtless due to the pro imity the of Wallakirk epidiorite . J . S G W

- - MICA SCHISTS CLA SLATES AND PH LLITES. , Y , Y

- - of The mica schists, clay slates, and phyllites on the east side the S f ff river pey orm a distinct series by themselves. These di erent members pass so gradually from the one into the other that it has f been ound impossible to separate them on the ground, the mapping being rendered still more difficult in Lower Banffshire by the thick

covering of drift. The phyllites are best developed in the area which lies between Keith and the Old Red Sandstone region to the south-east of Foch The ab ers . most typical section is found in the railway cutting below C the of M l S er raighead to west u ben tation, wh e the beds dip to

E 25 S . a of . at an aver ge angle These schists vary in colour from i h r are all l g t to dark g ey, and very fine in texture ; the bedding . lan s are n s f s of p e well defi ed, and their ur ace show minute puckering the lamellae. At several points in this section the phyllites contain 22 Exp lanation of Sheet 85.

- t of - and s u n s rains black schist, al o thin calcareo s bands up to i i ch in u in thickness . These latter are very siliceo s, and some instances - At end of approach the condition of a calc silicate . the east the section the schists alternate with a few bands of thin siliceous rock . Phyllites also occupy the wedge - shaped area which extends South - C u . to near raigellachie, and are generally inclined to the so th east At C 1 - of the C ummingston, and 000 yards to the south west hurch

- of B of . oharm, good bands clay slate are associated with them In the burn which flows from Gow Moss to Mills of Mulben the - and u phyllites have black schist partings thin white calcareo s bands , and simil ar calcareous beds are intercalated with purple phyllites f of M at the oot the burn of Forgie and below Newton . idway bet ween these two localities we find green unctuous schists with i a of u yellow streaks, wh le tow rds the head this b rn the phyllites the a become very fissile, lamin e in some cases being no thicker than - of . fia of a sheet paper Thick, ggy bands clay slate with schist are x of Tarr mount in partings e posed in the burn to the east y , and the vicinity of Foggie Moss some good bands of purple and green — a e clay slates h ve be n quarried for roofing slate . to of N of In the stream the west ewmill, north Keith, knotted mica-schists overlie fine grey fiaggy schists with very fine wavy u i a r cr mpling on the r bedding pl nes. In the rive and railway of section near the old railway station Keith, phyllite and clay slate bands alternate ; and along the same line of strike to the West

- - of Fife Keith these pass into strong grey mica schists . A well -marked belt of this schistose series stretches from a poin t near the head of Glen Rinnes to the eastern edge of the sheet at F orr habbie Coulalt the Hill of Shenwall . rom C y to the Wood the are u f in u f phyllites very ni orm in character ; grey colo r, o ten thick fla a and s u — at bedded and ggy, with a general dip to the e st o th east D u a Hardhau h varying angles . In the ll n Water between g and Nether Cluny the section displays bands of grey mica-schist and calcareous phyllites with occasional bands of black-schist intimately x of twisted and interfolded . There is also a good e posure this Fiddich Tull ochallum series in the river below , and at its western - f extremity phyllites and black schists are seen olded together. This is succeeded to the east by grey and fiaggy phyllites with of far calcareous schists, some the latter being so altered by metamorphic action as to have been converted into calc -silicate he s e hornfels of which t principal component is tremolite ( e Chap .

VII .i Frcm the river Fiddich to the burn of David ston the phyllites - fla a of s . On become ggy, and are intercalated with b nds mica schi t the north side of the Hill of Bellyhack there are numerous rock of f u - ex posures crumpled fiaggy garneti ero s mica schist . In the d eep ravine which lies to the south of the Mains of Pitlurg the rock slopes are composed of hard slaty green phyllites with calcareous bands and partings of mica-schist that have a general inclination to W f of r of h 1 O . i N . The ace the quar y at the west end t is rav ne is of e f e ft composed grey and gre n laggy phyllit s with so limy partings . 23 Metamorp hic Rocks.

The thick phyllites retain their original bedding, while the calcareous part ings show a distinct foliation at an oblique angle to - f their orignal planes of deposition. Thick bedded garneti erous mica- schists with partings of soft mica-schists containing actinolite occur at Mains of David ston . The Zone of phyllites and mi ca- schists which enters this sheet in G Fiddich F u f n the len orest is very m ch olded, the beds bei g either - On vertical or inclined to south east at high angles. the hill to the south - west of the lodge a roofing- slate quarry has formerly been - Bur wrought in a dark clay slate band. In the n Treble section the beds of grey phylli te are often vertical and contain thin bands of - J . S . G. . black schist . W The rapid alternation of the different zones of this Banffshire and a series the basic igneous rocks ssociated with them , produced i f at n d by isocl nal olding high a gles, is well illustrate in the continuous rock section exposed along the Blackwater for nearly r two miles above its jun ction with the Deve on . Ascending the Blackwater from the bridge we find grey phylli tes alternating with dark slaty schists containing incipient a n of knots , and also sever l thi sills basic rock, the whole arranged

a l r o the cast at a . vertic l y, c ‘ in lined to high ngles These are succeeded rather more than half-a- mile above the bridge by a u f o u r lentic lar in old f grey gritty q artzite or schistose g it, which is in contact on its eastern side with a basic sill containing c x calcite . This rock proves on microscopi e amination to have of i a a see B lost none its elast c ch r cter ( Chap. ands of this grey grit appear along successive isoclin al folds and are repeated five times between this point and the alluvial flat beneath the u ruined buildings a mile higher p the stream . The portions of the section between the grit outcrops are occupied by alterna of tions phyllite, black slate , knotted and andalusite schist, with

a s . . H. sever l gabbro ills L W. - of - In the south east corner the sheet, and to the north east of Crai water H and -s t f n the g ill , the phyllites black chis s are o te c of knotted, and also contain scattered rystals andalusite .

J S. . . G W 4 o 2 Explanation f Sheet 8 5.

CHAPTER V.

— d Metamorp hic Rocks continue .

GRANULITIC SCHISTS on THE CENTRAL HIGHLANDS

The assemblage of rocks which occupy the ground on either side of the Spey and Avon in the south-west portion of the map are those which have been described in the ex planation of the sheet to A the south (75) under the name of the Cromdale Hills Series . s this series is now regarded as part of the wide -spread group of C H of M S entral ighland rocks oine chist type, it has been thought advisable to discard this purely local designation . They may be described as a sil iceous series in which quartz is h f n generally the c ie constituent, but variable in character betwee ua - fla stones n to q rtzites, mica schists, and gneissose g , accordi g the relative amount and disposition of the felspar and micas present in them . Though the original elastic structure in these rocks has been i a u u are obl ter ted by s bseq ent movement, and they now holo u the a of crystalline and completely gran litic in character , pl nes original bedding are still often recognisable in the form of colour l a l a . fla stones of of Cow att b nds and dark amin e In the g the burn the , - of S of f near Knockando, north west the pey, planes alse or current bedding are clearly indicated by lines oblique to the bedding i a x n un planes. These dark lam n e when e ami ed der the microscope are foun d to be composed of heavy residual minerals such as ’ l t oflerin f of i meni e, rutile, and zircon, thus g a conclusive proo the u sedimentary origin of the rocks in which they occ r. The constant variation in the nature of these rocks is to a considerable degree no doubt due to original differences in sedi b ut u ff of e u mentation, may also be attrib ted to the e ects subs q ent of ns in mechanical movement . The area is one inte e plication, which the rocks have been thrown into a series of complex flattened l f ff m of ff isoc inal olds, along the di erent li bs which the di erential movement and consequent deformation varies in amoun t. So rapid r n of f e is the epetitio these olds, that where their cr sts are not the c visible, or have been removed by denudation, appearan e produced is that of regular parallel bedding with a general in clination to the east . The double-shafted arrows used in this portion of the map do of n of i not however represent the dip the origi al planes depos tion, i in of f and but ind cate the incl ation the oliation planes, which may, f e a i of the f indeed o ten do, coincid at any point long the l mbs olds with the bedding planes .

26 ” h 85 ap lanation of S eet .

fl u - h e tributaries. The aggy quartzites and q artz sc ists that are se n at intervals along the course of the main stream above the bridge at A M are of fine dvie ains, succeeded two miles south the bridge by a - in grained fissile mica schist, contain g small garnets, and aggregations of f of mica in the orm incipient knots . The schist is puckered and he u of cleaved, and t cleavage planes are obliq e to the planes f A oliation. good section of these schists is also given by the first tributary bu rn on the right (Burn of Garvault on the six-inch map) ; of c The apparent dip is south ast at somewhat low angles, and near the head of the stream the schists are s ucceeded by sheared quartzite with almost horizontal folding. Crossing the river Spey we find the ex treme south -west margin of u s - - fine- n the map occ pied by a grey mu covite biotite gneiss, grai ed, and u few s thoro ghly granulitic . The rock is only visible in a place of Auchna allin b ut x on the hill slopes two miles north g , is e tensively a t of C displ yed just beyond the western limi the sheet, in the ree D Carn hille Chearr of earg and on g , where it is in a high state - crystallization and filled with veins of reddish biotite granite. The somewhat conjectural boundary- line drawn northwards along f - of C and Cam Rui h Uain the dri t covered slopes arn an Loin g an , separates these gneisses from the siliceou s rocks of Moine Schist x type which cover a wide area to the north and east, e tending over the high moorlands which lie between the Spey and the head waters f A a of u f c o the Lossie . l rge part this area is ni ormly overed with - and if hill peat thick dr t, and it is only where the hill streams have cut deeply through these superficial deposits that the rocks are laid n of bare . The prevaili g type rock in this region is a more or less f u ua - in a elspathic q artzite or q rtz schist, which biotite, dissemin ted u u e t thro gh the rock in min te sp cks or flakes, is a constan though u of not abundant cons tituent. The amo nt shearing and interstitial t f movemen constantly varies , and the rock passes rapidly rom a comparatively unmoved and massive quartzite in to a thoroughly schistose rock in which white mica is abundantly developed along the planes of movement . The Burn of Tulchan and its tributaries afford perhaps the most continuous section of these rocks . In the deep ravines cut by the head waters of the stream the granulitic quartzite shows signs of much deformation and has been rendered thoroughly schistose . These schistose quartzites contain pink felspar and abun dant white u of B for mica. The b rn the lack Loch runs some distance along a of f u of the are line a lt, in the neighbourhood which quartzites B much shattered and disturbed . elow the junction of the All t an M far e Loin hor the quartzite is less schistos in character, and at Delyorn becomes a massive rock showing hardly any traces of B of - fi - movement. ands and thin seams mica schist or ne grained f i gneiss are reely ntercalated with the quartzites, and are sometimes of f H of su ficient breadth to be indicated on the map, as at the ill

Knocktulchan . A ff llt Gheallaidh similar section is a orded by the A , but here the rocks are much concealed by drift along the upper part

C f d - of the stream . ompressed ol ing in the quartzite is well seen in ’ e f o of P H n this s ction at the ot aul s ill, and also a short dista ce 2 Metamorp hic Rocks. 7

Pitch o of above r y Mill . At the latter locality a band grey mica a schist with small knots or aggregations is folded with the qu rtzites. These siliceous strata can also be observed at several localities of S at D along the course the pey, as alvey, Tulchan Lodge,

Achvochkie C of C Delna ot. A , the raigs allander, and p good section is laid bare on the western side of the Pool of Bund earg H immediately below the junction of the Avon with the Spey. ere a uartz ites t massive, b nded, purplish q al ernate with cleaved mica a schists. The dark bands in the quartzite dis tinctly indic te lines of original bedding, and the cleavage planes in the schist, which are li u is o f ob q e to the other div ional planes, do not pass int the ormer

. B Dal arvon rock elow g , where the river takes a sudden bend to the

a . east, the rocks become more gneissose in their gener l character Finc- - t and - grained granulitic bioti e muscovite biotite gneisses, with of occasional intercalations more siliceous rock, appear at Knockando H u a s i of o se, L ggan , and everal other po nts along the course the Spey between the mouth of the Kn ockando Burn and the western

H. u a L.W. bo nd ry of the Ben Rinnes granite.

UNDIFFERENTIATED Scnrsrs .

F a B B n D rom Knockando northw rds to the lack ur beyond allas, of - - the metamorphic rocks consist quartzo micaceous schists, with broad bands of muscovite -biotite -schist which have been separated - out from the more siliceous rocks . In the north west corner of the

map there is a small area of holocrystalline felspathic quartzite . The west end of the Eildon Hill is composed of a very hard pink a e s fla e quartzite lternating with micac ou ggy bands, and, associat d ‘ of fla — s f Raflord with these , a belt grey ggy mica schi t stretches rom M ona c u to the ughty Wood . This ro k is a coarse flaky m scovite — s f l a. f biotite schi t or gneiss, with wavy o i It o ten contains garnets, is x c and i and e tremely rich in mi a , in its l thological character closely resembles the muscovite-biotite- gneiss which has been separated from the Moine schists in the s urvey of the Central Highlands . H B B are fla The rocks around Westerton ouse, lack urn, ggy s of n u quartzo e and micaceous schists with bands pi k q artzite , and similar massive pink quartzites with pegmatite veins form the r al rocky slopes which surround the water reservoir at Fa n ey. To u of Blackhillock r of B B r the so th , nea the head the lack u n, there are fine flaggy quartz-schis ts with colour-banding parallel to the f i r s l oliat on planes, which a e inter ected by sma l granite dykes and veins. Thes e schists lie between two broad belts of muscovite - s and u in t in biotite gnei s, massive to gh character, and con ain g numerous lenticles and strings of quartzo-felspathic material f developed along the oliation planes . i the of Very l ttle rock is seen in valley the Lossie, but its tributary,

a B aff for . At the the L nnoo urn, ords a good section several miles head of the stream flaggy gneisses with several bands of crumpled muscovite-biotite-gneiss are inclined to the north-west at an average a e of and are s e se e of a e ngl ucc eded by a ri s hard, grey, m ssiv z ua s s Gl quart ites and q rtz schi t with small granite veins. The en ‘28 Exp lanation of Sheet 85. latterach waterfall is produced by a very massive band of quartzite di - a f pping to north e st, over which the stream precipitates itsel into a ravin e whose sides are formed by rocky cliffs 1 00 feet in height. For some distance below the cascade the beds are vertical , but d u of lower own, towards the mo th the stream , dip north and north ° west at 20 to and are chiefly grey gneissose flags with colour B f of banding parallel to the foliation planes . elow the cro ts Buinach the river Lossie flows for seme distance over a rocky floor

e of fla . compos d hard, grey , massive and ggy quartzites In the Gedloch Shou le B of and g urns, east the Lossie, the beds are holo li fla ston es of crystalline, granu tic, micaceous g , with bands hard , “ ” u A of Gedl och massive q artzite . t the upper end of t he Slogg the rock face of the ravine shows a fine pink quartzite very much ” a u C R . brecci ted, and not nlike the one Rock at othes Between Birchfield and cast of Hart Hill the rocks along the line of G R f ul i t the len othes a t are very much d s urbed and shattered, and are mainly composed of pink and dark grey massive qu artzites of u f with . bands more micaceous material . These are ni ormly a u t are holocryst lline and gran li ic in structure, and associat—ed with numerous small bands and one broad belt of muscovite biotite n l g e ss . In the Back Burn of Rothes massive quartzites and quartz -schist e w and - a vein d ith granite are inclined to east south e st, and apparently overlie a band of very fine light- grey muscovite - a u biotite gneiss with sm ll garnets, which is s cceeded by grey A ut a micaceous fiags tones with veins of granite and quartz . bo mile to the west of the village the Rothes Burn r uns between high ff of fia f cli s rather decomposed ggy micaceous schist, o ten very and s u gneissose , traversed by numerou small q artz and granite A D u v - veins . bove oomy Hall the rock passes into m sco ite biotite t of gneiss traversed by numerous dykes, veins, and len icles granite , and within half-a-mile of the Netherly diorite it is pierced by of Coulatt several small bosses of pink granite . In the burn the - - is of a fine t . e there an outcrop dr b grey, very grained quar zites Thes t and e f e in li are dis inctly bedded, in som cases show als bedd g ob que to the ordinary planes of deposition. * r M of E n of D . ackie lgin has made an elaborate i vestigation of B B f the granite veins and contact rocks the ack urn o Rothes . M f Chemical analyses were made by Dr. ackie rom five vein s (2 e- e 3 v - r veins biotit bearing v ins, and musco ite bea ing or pegmatite ) , and specimens were selected from the centre and margin of the veins “ ” “ ” along with prox imal and distal specimens from the quartz -schist The w the alongside. general results obtained ere that marginal e of the e the e zon s v ins are considerably more basic than centr , and “ ” in the marginal rocks the proximal specimens are more basic “ n r than the distal ones. The vei s a e also richer in potash at their ' n n in in a a margi s tha the centres , and the cont ct rocks there is “ ” marked excess of this element in the proximal as compared with

d of . the istal analyses , indicating an outward flow potash

J S. . G. W .

Trans . Ed in ur h Geo Societ Vol . iii Part i. . 98 . b g l . y, v , p I n ocks 29 g eous R .

CHAPTER VI.

’ IGNEOUS ROCKS .

The igneous rocks found within the area under consideration may t a be convenien ly arranged in two classes , ccording as they are shown by their structure to be earlier or later than the earth move t ff of ments hat have a ected the schistose rocks the region . The older plutonic intrusions of acid type consist of foliated mu scovite-granite or augen gneiss ; the basic rocks are represented

of f a n . by sills oli ted gabbro, epidiorite , and serpe tine The newer igneous masses include the great central area of the Ben Rinnes granite with its apophyses and marginal bas ic modifications on the north-east ; the small tract of unfoliated quartz -mica-diorite and serpentine in the ex treme so nth- west corner of the map ; a few later dykes of lamprophyre ; and a contemporaneous andesite of Old

Red S a e. H andstone g L. W. .

1 OLDER PL TONI MASSES . . U C — EPIDIORITES . The general character of the epidiorite in this sheet fi - a is that of a ne grained crystalline rock. It v ries in colour from l a and a ight to d rk green, in sever l localities contains garnets. It occurs in the Deveron Valley in small separate bosses and also as a portion of the western margin of the large Huntly area (sheet In the Blackwater and Glen Markie sections there are numerous F f of small sill s of this rock. rom the oot the burn of Edinglassie of Deveron Westerfold s n u in the valley the to the , a small to g e of a the large epidiorite are to the east enters this sheet. A specimen from Westfold s shows the rock to be afine-grained dark green foliated At f of u epidiorite or hornblende schist . the oot the b rn of Eding lassie this rock becomes very massive and has all the appearance of c u an altered rock with ontact minerals . It is q ite possible that the foliated granite at Q uarryhead may have been the cause of this

. Fu u Deveron Wallakirk alteration rther p the , near , there is a simi lar area of epidiorite which when traced to the sou th -west passes into the serpentinised gabbro of Craigs of Succoth and rn In M k Craigdo ey. the ar ie Water section numerous small sills and masses of epidiorite with garnets are intercalated with the - of G black schists and limestone len Markie. At the Newton of M Glen arkie the rock is very massive and fine grained. In the burn which runs past the farmhou se of Find ouran there is an ex posure of a grey green very finely foliated hornblende schist which

of t of No. 9 565 see C a appears along the edge the bel gabbro ( , h p. ' 30 Ex la a i n o h t 85 p n t o f S ee . — GABBRo. At Craigs of Succoth this rock produces bold craggy fe e A t Crai d orne atur s on both sides of the river . g y it is a m- e r a mediu grained dark gr y pe idotite, parti lly serpentinised in

. l f the places It consists principal y o diallage and olivine, latter

f No. 9563 see C a . mineral in places still remarkably resh ( , h p On the east side of the Brown Hil l the three craigs of Belcherrie S r d f— , uccoth, and Line rise above the sur oun ing tur peat of w and heather, and consist chiefly dark green serpentine ith a little gabbro . To the south this serpentine pas ses into a gabbro .

J . G. . S W. B f Deveron The river lackwater, rom its junction with the to the of ff of of edge the map , a ords a good section the series basic sills which form the northern prolongation of the sill of gabbro and e 7 5 has fu the pidiorite that crosses sheet , and been lly described in x a e planation ccompanying that sheet.

These rocks , though considerably altered, belong generally to the x he pyro ene rather than to t amphibole group . The most basic n f of portions are more or less serpe tinised, though this orm altera tion is not so complete as in the masses of serpentine seen around B f M lackwater Lodge , a mile or two urther south . icroscopic ex amination of some of these serpentines shows that they have f of x see resulted rom the decomposition pyro enes ( Chap. In c t n other ases the serpen i e has possibly been derived , by a process of f - of selective metamorphism, rom the olivine bearing portions the O a of gabbro . riginal cryst ls olivine can still be occasionally ni e f h t recog s d in the ormer rock, w ile his mineral appears to be absent from the gabbro where the latter shows no trace of z 2963 serpentini ation ( , B - l f u of B GAB RO. The broad si l that ollows the co rse the lackwater from the point where it bends to the south to the edge of the sheet f is composed o a partially uralitised gabbro. Under the mi cro scope the rock appears as a holocrystalline aggregate of plagioclase

the f . and augite, ormer being the predominant constituent The is a u augite , which a diallagic v riety, occurs in irreg lar masses and n of grains sometimes enclosed withi the plagioclase, and is mostly a r A the of turbid brown colou . long periphery the crystals it is f in a o ten altered to a fibrous green hornblende, which lso occurs in A confused masses of fibres and minute needles. t the foot of the s n t mall bur which joins the main stream on the wes , rather more a f-a- il e f of than h l m rom the margin the map, the rock is coarsely

s e of ni . cry tallin , and contains large individuals a gree sh mineral Here also the augite is mostly altered into green or brown acicular of n i and fibrous hornblende, and it is these aggregates acti ol tic hornblende which give rise to the green silky patches that are so The e conspicuous in the rock . wavy app arance of the striae of some of the augites is suggestive of internal movement d ue to ex traneous pressure . Parallel structure is everywhere more or less apparent in these s f l e n gabbro , but the o iation is more complete along c rtai bands the of re f which , in coarser portions the rock, call the beauti ul

of Pooldhulie S Don. . . H foliated gabbro in trath L W . R ks 31 Igneous oc .

FOLIATED GRANITE —The foliated granite to the west of Keith occupies a long oval area which ex tends from Auchlunkart Lodge to North Eoghain and embraces the upper portion of the Hill of Muld er x u of are in ie. The best e pos res this rock to be seen several small quarries to the east of M idtown and at the head of the small At f burn which runs past C ullieshangan . the ormer locality the

28 S . foliation planes are inclined E . at The rock is partially decomposed and is a light -brown coarse granitoid mica ceous gneiss wi th more or less isolated and drawn-out augen h S m s aped masses or kernels of felspar . ( ome notes on its icroscopic

a . char cters will be found in Chap. VII ) of Fife- of To the east Keith on the banks the river Isla, and in a u of s q arry between the railway station and the edge the heet, there are good exposures of a belt of foliated granite identical with that f a a a seen at Muld eric. The oli tion pl nes vary consider bly in their

5 N. S . 8 . of direction from E. to W with an average angle Parallel to this band and about 400 yards to the cas t a similar x f a oldhome - a of and zone e tends rom ne r C to the north e st Keith , is i - f n all probability the Fife Keith belt repeated by olding. The best sec tion is seen in the quarry to the south of the Roman - Ca C c a fine . tholic hapel, where the ro k is grained silvery grey gneiss Between the Carran and Bellyhack Hills the ground is covered u r u of f u with n me ous ang lar blocks this oliated granite, and altho gh no rock is actually seen in place its presence is inferred from the uarr hill of abundance of the loose debris . The q y to the west n i of au I vermark e is also covered by debris gen gneiss.

S . G. . J . W

NEWER PLUTONIC Rocxs . — GRANITE The great central mass of granite forms tw o areas of of S unequal size lying on either side the river pey . They are probably continuous beneath the alluvium immediately opposite A u u of Ruthrie B a berlo r, but between the mo th the urn and L ggan are separated at the surface by a thin strip or bridge of meta is of the morphic rock which seen in the steep northern bank river. The larger area s outh of the Spey covers nearly 24 square miles of ground between Ben Rinn es and Dufftown . Its longer axis x for six l s - e tends mi e in a north east direction , parallel to the strike u a of the schists . The northern mass occ pies an are three miles by in x of of A two e tent, which the village rchiestown is the centre . Its x i of e act l mits are somewhat uncertain, the position the n bou daries being generally obscured by drift. The boundary line

“ drawn along the slopes of the Hunt and Stob Hills is indeed only x u on u mi of an appro imate one ; since where the gro nd , as the s m t H H of f x of unt ill, is bare dri t it presents a ple us igneous and n a in metamorphic rocks , the i terl cing ve s and apophyses from the main mass of granite traversing and isolating portions of the sur x rounding schists in a most comple manner . That this is the nature of the j unction all along the northern boundary of the granite is indicated by the innumerable veins seen in all the stream e e the s are x sections and wher v r rock e posed. 32 5 Exp lanation of Sheet 8 .

In none of these intrusions is there any appearance of a chilled edge ; in deed the thin veins are as coarsely crystalline up to their th in n margins as e terior portions of the main mass . The vei s have u n n n of f us ally bee i jected more or less along the pla es oliation, b ut occasionally a broader vein is seen to out these latter at a high the e angle, sending out thin branch veins on either side along plan s of schistosity. of s the In addition to this direct introduction igneou veins, rocks along the granite border are often so much impregnated w ith granitic material that the structure becomes granitic rather ul t than gran itic . This phenomenon is particularly no iceable at the bri dge of Craigellachie and in the railway cutting close to the t is station , where this in erstitial permeation so complete that it is often difficult to distinguish the altered quartzite from the original igneous rock . Q uarries have recently been opened on the northern flanks of B u H of A u few r f the l e ill berlo r , a hund ed yards rom the northern of Ben R the edge the innes granite , intervening ground being filled with veins and apophyses from this igneous mass . The rock exposed in the quarries is a granulitic muscovite -biotite-gneiss or l n and l s b ut schist, general y fine grai ed tolerably si iceou , with

occasional coarse and more gneissose bands. It is filled with parallel veins or bands of granitic quartzo-felspathic material a - on f varying from less th n g inch to e oot in thickness. They are f - of generally parallel to the oliation planes the schist, but occasionally send branches or strings across from one vein to

another . The thicker veins tend to become coarser in the centre, b ut l x of nothing like a chi led edge e ists , and an interlocking the marginal crystals of the vein with those of the surrounding schist

can often be detected . Certain of the veins swell out at intervals into lenticu lar or eye of f shaped masses, some which seem to be isolated rom one another, of while others are connected by a thin string the same material . These augen -like masses are generally sheathed or surroun ded by thin bands in which biotite is considerably more abundant than in the rest of the rock suggesting a separation of the more acid from - n the ferro magnesian minerals al ong certai lines . While the direct intru sion of granitic material along the lines of discontinuity in the schists has u sually been s u ggested as the cau se f s ma d ue o the e phenomena , it is possible that they y also be to segregation of the quartzo-felspathic elements in the surrou nding t u u rock . Whe her we attrib te these appearances to direct intr sion , to a c m of segreg tion, or to a o bination both causes , we may with certainty assume that they are intimately connected with the f n t u of Ben R and of - r period o i r sion the innes granite , are late origin than the movements which produced the schistosity of the rocks in which they appear . The principal constituents of the ordinary type of Ben Rinnes are u f the granite q artz , orthoclase and oligoclase elspar, and biotite ; t s a t last named mineral being generally scanty , and some ime l ogether of o u absent . Varieties the granite also cc r in which microcline ,

u v see C . m sco ite , sphene, and allanite are present ( hap

34 Exp lanation of Sheet 85.

s een on Hun t Hill and round Craigellachie also strongly recall the x of comple system apophyses, inclusions, and detached veins observed of Mon dhliath A along the edge the a granite mass at viemore, and Buil at Loch g in the Eastern Cairngorms . O of x u of Ben wing to the want e pos res, the contact zone the Rinnes granite and the Banffshire series affords little evidence of thermo - metamorphism ; but in the region north of the Spey the N etherly diorite has produced hornfelsing in those portions of the s urrounding schists that were from their original composition of capable being altered in this manner . The minerals found in the andalusite and cordierite -hornfels in the burn of Rothes are essentially the s ame as those of the cordierite rocks near the C r 5 A ai ngorm granite in sheet 7 (see Chap . nother characteristic feature of the Cairngorm granite is found in the “ scurrans or weathered rock-masses that crown the summit of Ben Rinnes and show well - marked tabular weathering along their

horizontal joints . The facts adduced above show the striking resemblance in i n composition, var ation, and relations with the surroundi g rocks a x Ben R C and th t e ist between the innes and airngorm granites, of indicate the close relationship the two masses. It therefore i f l seems h ghly probable that the ormer, as wel as other outlying of o masses to the north and west, belong to the period intrusion f a f the great granite are in the south ; and urther, may, as suggested x 75 some years ago in the e planation to sheet , be regarded as protrusions from an underlying and continuous floor of igneous

rock . A of S at C Dalmunach P long the banks the pey arron , , ool Leek , and Creag Neach ; in the cutting under Knockando House ; and u Dalb eallie S t fla s tones beneath the alluvi m near ta ion, the quartz g are pierced by numerous veins and sills of red granitite containing

a a u a u . orthocl se, oligocl se, q artz, and b ndant biotite In the crag that overhangs Pool Leek the junction between the two rocks is ’ u well seen. The q artzite at the water s edge rests upon the upper s urface of a sill of granite which is coarse-grained to the edge and A a shows no sign of a chilled margin. sm ll outlying mass of the Ben Ri f n Parkhead f-a- t nnes granite is also ou d at , hal mile nor h of - G Farclas D . nt of ua but len istillery It co ains inclusions q rtz schist, for is much decomposed , and is quarried at the roadside sand. DI IT — of t OR E. The small patch basic igneous rock tha crosses the x - of Burnshead How e treme south east corner the map at Three , forms part of a large area of quartz -mica - diorite lying to the sou th of the Tap of Noth in the adjoining sheets It is a coarse of u granitoid rock which the essential constituents are q artz, n of plagioclase, biotite, and hor blende, with no signs parallel structure, and shows the characteristic weathering into spheroidal of A masses common to so many the berdeenshire diorites . The serpentine that appears on the east side of the diorite is possibly an a - of the e ltered ultra basic modification sam intrusion, but the boun dary and relations between the two rocks are obscured by the - thick covering of boulder clay . e/cs 35 Igneous Ro .

The evidence is in favour of separat ing these rocks from the f of Deveron B oliated epidiorites and gabbros the and lackwater, and assigning them to a later period of intrusion . A — Tu ua - f ff L MPROPHYRE. the q rtz schists that orm the steep cli s a the S at H u P u -f u of that ri es bove pey ollyb sh ool, abo t three o rths a a of Aikenwa t f u of fine mile e st y, here are three or o r thin sills a a - a a u gr ined greenish red b sic rock gener lly m ch decomposed. The c a ma b ut f t ro k is indic ted on the p as a camptonite, rom its charac er u i F t nder the microscope t is regarded by D r. le t as a dioritic lamprophyre . The microscopic characters and s ystematic position of are u this rock disc ssed in Chapter VII . Ex lanatio o S eet 85 p n f h .

CHAPTER VII.

’ PE TROGRAPHY OF THE AREA .

THE D I I E . I . LATER GRANITES AN D OR T S

Of the newer granites which date from a period su bsequ ent to the t of the f at an d c s t the u u a developmen oli ion, hen e pre en s l st u ctu s of ut c u as s s at m s x r re pl oni igneo s m e , only one gre a s e ists

‘ t that of Ben R s an d th C u ai . ma in his area , inne e o v s The s ller

t u at Netherl Dan d aleith . u m in r sions y, , etc , tho gh ore basic in c a c m a f u t th m h ra ter , show so ny evidences o consang inity o e ore a t t a t cid yp e h t hey are best regarded as its marginal modifications . A complete series of gradations from the most acid m u s covite pegmatites to the quartz -au gite -diorites can be traced in the c s c s ct s l a s for u t a a a mi ro copi e ion , and e ve no room do b th t they h ve t a s A i i w wn gene ic rel tion hip . sim lar as s ociation s ell kno in the le " ‘ of Cairn orms S u U lan d s i Garabal H granite the g f the o thern p , ill; ” an d s el ewhere in Scotland . Ben R a as the t r s of a The innes gr nite , seen on nor he n lopes th t m u t and c t of A u is st a s -c u o n ain in the vi ini y berlo r , mo ly fle h olo red a t of m u m a an d c ua t w t t biotite gr ni e , edi gr in ri h in q r z hile bio i e , the a - c u f -m a s a t t only d rk olo red erro gne i n silica e , is never presen in

a u t and is s im a t . B t gre t q anti y , omet es lmost absen o h in the hand specimens an d u nder the microscope it clos ely res embles the Cairn

m a t of w c it is all a t ut m as s . gor gr ni e , hi h in p rob bili y an o lying Its a a flesh-c u f s a w c as princip l ingredient is olo red el p r, hich o c ion a s w s a c to t c m t and s to lly ho tenden y porphyri i develop en , prove be m t t w t u i M c is os ly or hoclase i h s bord inate ol goclas e . icro line not c c a ft t t c u u ac ommon , the ortho l se is o en per hi i and s rro nds the id a a u t is scarce and for t a t pl giocl se m scovi e very , the mos p r a A tt c at t u a t m cu é n second ry . li le mi ropegm i e (q r z ver i l ) is ot f u O as the a m S w -d efin in req ent . cc ionally h nd speci ens ho an ill ed t uc u an d u m ac of atac a t parallel s r t re , nder the icroscope tr es c l s ic ac ti s t tion are rarely en rely ab en . a as a the Ben R s x u f T ken whole , inne granite is e ceedingly ni orm u u b ut w a of u a thro gho t , to ards the m rgins its o tcrop v rietal of a ccu hu u a at modifications sever l kinds o r . T s in the q rry Ruthrie A u a i v u , berlo r, a grey gr nite is obta ned , ob io sly richer in a the of Ben R f c a a biotite th n granite innes , rom whi h lso the pe rly w t u of f a t hi e or grey colo r its elsp r distinguishes it . This grani e

Memoirs of the Geo o ica Sur e Scot and . E anation of Sheet 5 b Lione W. l g l v y, l xpl 7 y l

Hinxman B. A. with a Petro o ica Cha ter b J J . H. Teal M A. F.R.S. 1 896. , , l g l p y . l, ,

Memoirs of the Geolo ica Sur e . The Si urian Roc s Vol . l . S cot and . B B . N. 1 g l v y l k , , l y

Peach F. R.S. and ohn Horne F.R..S , , J ,

The P uto nic Roc s of ara l nd M l a H. Tea and G b al Hi a ea l Bre c b . . I l k l , y J J ll,

. R. Dak ns uart. our. Geo . Soc. Vol iii . 104. J y , Q J l , . xxv , p 37 Petrograp hy of the Area.

te c - a of f m is rich in sphene and allani , the herry red gr ins the or er and black or coffee-brown prisms of the latter being eas ily detected t on the surface of the hand specim ens with the aid of a pocke lens . The sphenes are often in inte rpenetrating cross twins ; the allanite a - n s m w in elongated d rk brow , zonal prisms , sometime si ply t inned c c are f on the orthopinakoid an d slightly pleo hroi . They per ectly c the a s u u ua idiomorphi , tr n verse sections being bo nded by the s l s ix fac s 001 1 01 1 00 an d out e ( , , ) resembling hornblende in their

s . s c c ta m u a c c line Thi ro k on ins ch oligocl se , perthiti ortho lase , and a c ct w mu v little mi ropegmatite . The se ions sho no sco ite , and no cataclastic structures . Allanite occurs also in the granite which forms a little mass at Ca th s ar is s rron on e Spey . In the rock lice one l ge prism een in - d is u i a s c . a w u an longit d n l e tion It has a d rk bro n colo r , highly

a . t t a u t of Ben zon l The rock is a reddish bio i e gr nite , not nlike hat R b ut c innes ri her in biotite .

W. of Du ff u c a of N C u tw o S .S . The m s ovite gr nite ether l ny , miles

t n of u t a ff t t . It is a a a s ow , is q i e di eren yp e prob bly vein or pophy is of the m a ma x s m a t am the in ss , and is e po ed in a s ll s re by roadside in c tact w a u a t t B t is a s t m u c t w c on ith q r zi e . ioti e b en ; s ovi e, hi h is s a the Ben R a t is e a u a t an d f a c rce in innes gr ni e , her b nd n , the elsp r is a m . a c u of u a l rgely icrocline The rock is p le olo red , medi m gr in , an d the numerou s plates of muscovite s cattered over their su rfaces give the hand specimens a very characteristic appearance . The quartz and fels par tend t o occur in rather coarse graphic inter w th w t of gro th . In e points in hich it differs from the typical grani e Ben R s c a ac s the a t s an d m u sc t m a innes , thi ro k ppro he pli e ovi e peg t os of w c t are m a x am s the s of t . it , hi h here ny e ple in dyke his region H has t ct the Ben R s n t ornblende not been de e ed in inne gra i e , w t t st x A w a a f m a i h one in ere ing e ception . s ection s prep red ro s u a c u fine- c us a as of mall , ro nded, d rk olo red , grained in l ion in m s M a t at of Ruthrie a A u . It t o gr ni e illtown , bove berlo r proved be an intim ate admixture of hornfelsed biotite gneis s with veins of

t . E of tw o c s s s its c a a s u the diori e ach the ro k pre erve h r cter , tho gh s st su u n att is chi is rro nded a d penetrated by the diorite . The l er at fine a c in t la and s w c f r her gr ined , ri h or hoc se in phene , hi h o ten

c f a s a a c as f s . and en loses well ormed , l th h ped pl gio l e elspar , in one crystal show s lamellar polysynthetic twinning parallel to the face of the s H is t c a pri m ornblende mos ly idiomorphi , only r rely

c f s a . B w c is a u a t c is en losing a el p r iotite , hi h b nd n in the s hist , act ca a s t f f u c pr i lly b en rom the diorite . In these eat res this ro k c s s s s s and s w c now lo ely re emble the yenite diorite , hi h we pass to consider . At Dand aleith Stat a a s a f wa Crai el ion , long the ro d ide , h l y to g ac B t is m t x u f - u l hie ridge , here a li i ed e pos re o a dark colo red f , o the a are dioritic rock which . princip l ingredients dark green an d fle h-c — s u s s c f s a . hornblende , olo red , or ometime bri k red el p r F t mas s a w a as rom this lit le sever l specimens ere prep red , and m b e u c f the a s m n t ight s spe ted rom h nd peci e s , it is not altoge her - u nif . al is a ua d o orm in character The prev ent typ e q rtz i rite , con of f ls a n sisting green hornblende , plagioclase e par , and v ryi g 38 Exp lanation of Sheet 85.

u s of u . s t uctu is t amo nt q artz The r re not ophi ic , the hornblende

t . a f f a h. no having cryst llised be ore the elsp r, whic it does enclose But t a a nt an d of c or hocl se is never bse , in some the se tions it is the dominant felspar " the rock might then be regarded as a t syeni e . The sections show no biotite " red dish pleochroic sphene is a u t an u b ndan d cons picu ous in the hand s pecimens . It occ rs in a c t cl a -s a a f a and l rge ophiti pla es , en osing l th h ped pl gioclase elsp rs , has f m a u tu r w c vi i a very per ect la ell r str c e , hi h is e nced by stra ght , perfectly continu ou s cleavages parallel to the prism fac es * h u u has u u t a w T is str ct re s ally been as cribed o repe ted t inning , and betw een cros s ed nicols it is obviou s that the crystals are poly s t c the c i c u u s u a yn heti , se tions be ng rossed by n mero colo r b nds w c run a a t o the c ea a an d ma tw o s hi h p r llel l v ge , y be in eries d ct a . E t u a t t s c an interse ing one nother pido e is ab nd n in hi ro k , h as m t w c w c ma a t . St u x so e imes bro n ores , hi h y be llani e o t , he a a s of a are f u t an d a few are w d h gon l prism ap tite req en , cro ed wit minute dark enclosu res b ut these are far more characteristic of the t of Neth rl diori e e y. the w a the 0011 6 Book u of R t a In ood bove , one mile so th o hes , l rge of st the su fac of the u a blocks diorite lie rewn over r e gro nd , prob bly w at out f u m s c c a u c e hered o a s bjacent as s . Thi ro k ont ins m h grey - f u a t an d t t . elspar , ab nd n dark green hornblende , no bio i e It a fa a u t of ua t an d uc t to cont ins a ir mo n q r z , so m h or hoclase as e e it a as a s t . S u a t ntitl to be reg rded yeni e phene is ab nd n , a l fels ar ‘ w a at occasion l y enclosing a p ,i and sho s the lamell r pl y st u u t t c of s t t c t . r ct re , wi h only ra es poly yn he i winning The horn is c s c r an d the blende rather de ompo ed , hlo ite epidote being products . The t of Netherl is x R Burn diori e y well e posed in the othes ,

a c a. a t and is in the h nd spe imen h ndsome rock wi h hornblende, a t an d ua and f a of m di u black gl ncing bioti e , greyish q rtz elsp r , e m

an d . It a a or rather coarse grain , not porphyritic is more norm l t t t c as a a n an d diori e han hose already des ribed, pl giocl se , zo al s tim fa as f m s f a u t ome es irly b ic , or its principal elsp r , tho gh or ho t m clase is present in qu it e subordinate amount . The bio ite so e t m c a as a u not . A i es encloses plagio l se , the hornblende r le does tt - x u li le grey green pyro ene occ rs , enveloped in dark green horn m a ft f u to c atc s of the blende . The one iner l is o en o nd en lose p he t x u shi s u a u u u an d other, each hen e ting i ng im lt neo sly thro gho t , a th probably they are in parallel intergrowth . In many c ses e c a t a c an d hornblende has paler entres , giving it spo ted appe ran e , it is in every way probable that au git e originally formed the cores r ac of such c y stals . The hornblende is similar in char ter to that i t of Dand aleith au s s a a in the d ori e , the gite how no di llage lamin S s f u c u u f tion . phene is les req ent in this ro k , and s ally orms thin

* Wi iams G. H. C ea a e in American S hene. American ourna of Science ll , l v g p J l ,

V l . i . . 486 o xx x , p ' ’ - Mu e O. e er d urch Druch entatand ene Zwi in e von Titanit . Neues J ahrbuch gg , U b ll g fur Minera o ie Band ii. . 98 . l g , The Ra pake ur e of Lawson A. R. m Re i on. Ann. Re ort of the Geo . S , g p l v y 124 Fi 1 Canad a Pt . i., p . , g . 1 .

" ' Mackie W . On Differences of C om osition etween the Centra and Mar ina I , p b l g l

Portions of Granitic Veins . Trans . Ed in. Geo . Soc . Vol . iii. Pt . i . . 94. l , v , , p rea 39 Petrograp hy of the A .

a u x . A at a u a t a rings ro nd iron o ides p ite is very “ b nd n in l rge , u c are sto t , idiomorphic prisms , whi h so filled with little dark u at t i enclosures as to become qu ite opaq e heir centres , wh le sometimes a thin external zone is perfectly clear and transparent . As u s c u s are m a to a u a r le , the e en los re too s ll reveal their n t re u th st w b ut of t m u even nder e highe po ers , the largest he are fl id a a t n ot c c cavities w ith m obile bu bbles . These p ti es are pleo hroi , b ut s imilar crystals occu r in a sm all intrusive m ass or large vein w c as of C a ac u and is hi h pierces the s chis ts a little e t r igell hie t nnel ,

' exposed in the railway cutting ; and here the pleochroism is a and as the at c c u m rked , nicol is rot ed the se tion changes olo r - — Su from pale yellow brow n to dark greyish blue or black . ch

apatites are more frequ ent in volcanic than in plutonic rocks . The qu art z of this diorite is often filled with dark hairs of u a f atu w c c sta t cu s the u c s r tile , e re hi h on n ly re r in pl toni mas es in t s a f s a a s c ta m u u u s hi rea. The el p rs l o on in in te opaq e enclos re u i s at st tw o s w t a t a reg larly d spo ed in lea eries , i h defini e orient

t c c u n ot x ct m . s it m a ion whi h o ld be e a ly deter ined The e , y be t out are c a ac c a s of the m b asic poin ed , h r teristi s l o ore rocks ~ a c at w t the Ga wa t s to c the El in shire sso i ed i h llo y grani e , whi h g

diorit es present a strong res emblance . At St H a tt u t of Netherl a t x d ob ill, li le so h y, diori e is e pose , s t a t o t at u c xc t the t r e sen ially simil r h j st des ribed , e ep in grea e

a u a c of t w s the c a st a c . b nd n e bio ite , hich give ro k di inctive appear n e H s is a u a t a t a u u s ere , too , phene not b nd n ; the ap ti es h ve n mero a u ca t s b ut are n ot u st an d a u the l rge fl id vi ie , d y op q e hornblende ft t s w ma a f m x has o en paler cen re , hich y h ve originated ro a pyro ene, t u t th ho gh hat mineral was not present in e rock s ection . The f s s c ta the u a u c u el par on in reg larly arranged op q e en los res . In the quartz diorites of Netherly and Stob Hill it is frequ ent the s a s s t st c s of w c to find hornblende in pongy m s e , the in er i e hi h are u u f filled p with q artz or acid elspar (see Fig . The st uc u c t c ft a c as the s c r t re is mi ropoikili i , or o en gr phi , attered

c of ua ma x u s m u a u . ma pat hes q rtz y e ting ish i lt neo sly They y, u t t a of uart su u i moreover , be in optical contin i y wi h reas q z rro nd ng the hornblende and filled with fluid cavities and ru tile hairs ; This uf s of the c is is s ficient to e tablish the identity mineral , whi h dis tinguished also from apatite and early basic plagioclase by its index of f ct re ra ion . The periods of crystallis ation of the hornblende and the quartz were too widely separated to allow u s to suppose that this is a a c t t d u e t u u gr phi in ergrow h o sim ltaneo s crystallis ation . The hornblende had practically ceased to form before the plagioclase f a t an d the it u d elspar had st r ed , latter in s t rn entirely precede the u A m q artz . si ilar relationship between these tw o m inerals has ale s Romb er who a it w ct been de cribed by g , comp res ith the conta u u c S m ‘ i and . w str ct res des ribed by alo on others It may , ho ever , be

“ Rom er J . Petro ra hische ntersuchun en an Diorit Ga ro und Am hi b g , g p U g , bb , p b ol esteinen. Neues J ahrb uch fur Minera o ie ix . Bei a e Band 30 g l g , l g p . 7 . Sa omon W. e er eini e Einschliisse metamor her Gesteine im T na it Ne es " l , U b g p o l . u vi ahr uch fur Minera o ie i . Bei a e Band . 482 483. J b l g , l g pp ,

Sa omon W. Geo o ische und Petro ra hische Stud ien am Monte Aviol i It ieni c en l , l g g p o n al s h o Anthei d er Ad amell ru e. Zel ts . d er d eutschen Geo . Ges s ell . B . 42. . 4 0 l g pp l , p 5 . 40 E xp lanation of Sheet 85.

u a a c s as a a c m ch more prob bly s ribed to corro ion, in c se des ribed by ale M l f Ries en eb ir e i ch in his paper on the Granitic Rocks o the g g , where he discu sses the origin of a s im ilar relationship between and u c has biotite q artz . In the Elginshire ro ks the biotite b u t t u c xt indeed been corroded, o a m h less e ent than the horn is ft rf blende, which o en pe ectly honeycombed . Corrosion of the hornblende occurs onl y in the presence of t as the t s of Dan d al ith and Ge R c bio ite , , in diori e e the ne o k , where

s c . S of biotite is absent , the hornblende is alway ompact ome the Netherl t u u ff c t s hornblendes in the y diori e are q ite na e ted , and ho e most corroded are u su ally associated with biotite in such a way as to su ggest that by the rapid growth of the latter the m agma had a t a t c the tw o been locally en bled o t a k the hornblende . Where min erals are clu stered together there is often between them a a of ua the s t u a ma w c n rrow seam q rtz , representing ill fl id m g hi h acted as the medium for a transfer of the molecules from one the the mineral to other . The qu artz an d felspar which fill c i are u t fu of a c of a av ties q i e ll sm ll rystals apatite and m gnetite , the st c n s u of s are a s it characteri i e clo res the hornblende . The e l o , ul t v few a t f m sho d be remarked, ei her ery or entirely bsen ro the a u t f th s as a f atu of norm l q ar z o e rock . Thi has been noted e re minerals filling corrosion spaces by Backstromi‘ and by Milchi That resorption did n ot begin till a comparatively late period in the con solidation of the rock is show n by the fact that where a crystal w as entirely enclosed by biotite it has escaped ; where protected only on three sides the liqu id magma has eaten its w ay into the crystal f x s s u f Fi a a the ca rom its e po ed r ace ( g . The m teri l filling vities

is a w the a s uc of c a sa . ua l ays l te t prod ts ryst lli tion , viz , q rtz , ortho

c and ca a an ac c a c as . lase , very oc sion lly id plagio l se (oligo l e) The developmental history mus t have been s om ew hat as follow s H and w as f w a ornblende preceded biotite , ollo ed by pl gioclase f a u the of f m at of t t w elsp r , tho gh periods or ion hose hree ere not

absolutely consecu tive b ut to a s light ext ent overlapped . The a a new c and a um and the a a s m gm , highly a id rich in l ina lk lie a fa c f a u a t c the (h ving in ct the omposition o e rite or pli e) , orroded r d w x its c f m t t a at ho nblen e here e p osed to a tion , or ing bio i e p rtly

ow n x s t t at of . its e pen e , par ly at h the hornblende The formation of biotite from the corrosion of hornblende (and of x b c a a has s c m a also pyro ene) y a id m gm s , been de ribed by ny w B H P ” riters ; among others by ecke, " olland ,“ arkinson ,

“ Mi ch L. Beitra e z ur Kenntniss d er Granitischen Gesteine d es Riesen e ir es l , g g b g .

Neues J ahrb uch fur Minera o ie xii . Bei a e Band . 1 45. l g , l g p

Bac strom H. e er fremd e Gesteinseinschlus se in eini en s and ina ischen " k , U b g k v - Diab as en . Bihan til . Svenska Vet A ad . Hand lin ar Bd . xvi . Part ii. No. i . g l K k g , , , Stockholm

Milch L. Beitra e z ur Kenntniss d er Granitis chen Gestein d es Riesen e ir es . I , g g b g

Ncues ahr uch fur Minera o ie xii. Bei a e Band . 1 45 J b l g , l g p . ' Bec e F. Petro ra his che Stud ien am Tona it d er Ries erferner. Ts chermak s Min . " k , g p l

Mittheilu e B nd i. 4 Petrog . n, a xii p . 08 .

So as W . . n the Vo canic District of C ar in ford and S ie e Gul ion Pt. i. On ll , J l l g l v l , - the Re ation of the Granite to the Ga ro of Barnavave Car in ford . Trans . Ro a Iris h l bb , l g y l

Acad em Vol . . . 477 and 494 y, xxx , p Ho and T. H. n Au ite Diorite with Micro e matite in Southern Ind ia. uart . 1T ll , g p g Q

our. Geo . Soc . Vol . iii. . 405 J l , l , p Par inson ohn. On an Intrus ion of Granite into Dia ase at Sore Point Northern k , J b l (

erse . uart . our. Geo . Soc. Vol . lvi. . 340 J y) Q J l , , p

42 t 5 Exp lanation of Shee 8 . of u s ch an origin. Rosenbu s ch has remarked that the principal pau se in the crys tallisation of the diorites takes place after the f of a f s and f of a ormation the pl gioclase els par , be ore that the lkali f a s and of u rt to s h is elsp r the q a z . It is thi period t at this action to as E f of of be signed . xamination of a series o sections rocks this u w gro p has sho n that this s tructure is by no means rare , though not often so well developed as in the diorites u nder consideration . The dykes which proceed from the granitic mass es and intersect the s chists in the vicinity of Craigellachie and Rothes in great u are c t c and n mbers , in most ases of a grani i character show little a at f v ri ion rom the type of the parent mass . They are fine to di u t s c u me m grained grani e , not porphyriti , and witho t any chilled

s . S at n s edge ome are r her basic a d rich in biotite and phene , s other more acid and approach aplites in composition . s s c s of u r of R t of c In the gnei ses and hi ts the b n o hes , veins a oarse u t f s a l a a m scovite pegma ite occur . The el p r is o igocl se and an lkali f w a u ur A f w elspar hich r rely shows microcline str ct e . e small u ar s ar m u v f t ro nded g net e present . The sco ite is o ten s ained dark an red by infiltration of haem atite along its cleavage planes . The s w efiects of s r A u u f atu of s rock sho hea ing . c rio s e re these dyke is c of s of ua t a its c ic t a the presen e a tring q r z long entre , ind a ing th t c rystallis ation proceeded inwards from the margin s of the vein . u The q artz contains m any large fluid cavities with mobile bubbles . Only one rock of the lamprophyre grou p has been detected in

the m a as . f m t this area , indicated on p camptonite It or s a hin

the u Aikenw a S Mu . sill in q artzites at y on the pey , near lben The c at c u t ro k is r her fine grained , dark olo red , wi h small elongated

s s and d f . U hornblende pri m , re dened , decomposed elspar nder the microscope a greenish-brown hornblende is the most conspicuou s

a c s . miner l , in idiomorphi pri ms , not greatly elongated The trans u f f 1 1 0 01 0 1 00 verse section is bo nded by the ollowing aces, , , and , cc r 001 the last only o asionally and ve y small . It is terminated by an d I l l . the usua at c c a a It has l prism i le v ge well developed , and m —a w 6 n s a pleochrois , pale greenish yello ; , brow i h green ; , darker

t w . the a a green ; sligh ly bro n Twinning on orthopin koid is r re . A st u u t the pale green , almo colo rless a gi e is present also , and like r hornblende mostly free from enclosu res . The tw o minerals a e

f ia b ut not a . o ten assoc ted , apparently in par llel growth The x fa u is not u u has pyro ene is irly ab ndant , s ally idiomorphic , and uff f s t u of possibly s ered rom corro ion , ho gh traces the prism and s s th pinakoids are sometime vi ible in e transvers e section . It is uc wi c m h decomposed and filled th hlorite , serpentine and calcite , b ut f u when resh gives brilliant polarisation colo rs, and has a high ° xt 40 S t u f angle of e inction ( and over) . cattered hro gh the elspar there is much yellow epidote in little grains which do not appear to have resu lted from the decomposition of a second generation of ferromagnes ian minerals ; sm all hornblendes occur b ut they have all ha of s f da the c racters the larger crystal , and a per ect gra tion in h r size can be traced , so that the rock is not porp yritic in the prope - of the . F a r sense term elsp r in long lath shaped c ystals , some w di f and hat ra ally disposed , envelops the erromagnesian minerals f a r f t u is o l te orma ion , tho gh not entirely , as sometimes a hornblende a Petrograp hy of the Are .

r a f a ic f m a r . su rounds elsp r , to wh h it or s na row border In ” d are a longitu dinal section such hornblen es swallow t iled, with M of the f hollow ends filled up with a felspar crystal . ost elspar n w shows polysy thetic t inning , and appears to belong to andesine b ut of and allied varieties , in the thinnest parts the section it is i u a a t u a obv o s th t orthocl se is presen , s rrounding the plagiocl se, and st f in places it is dappled like anorthoclase . The late elspar is intergrown in a rude graphic fashi on with a sparing amount of u w f rm s a the f q artz , hich o s also an inter titial materi l between elspar s x a prisms . The acces s ory mineral are iron o ides , we thering to c x and m t a a e um u leu o ene li oni e , and p tit in n ero s long , pointed

needles . s ri Thi rock is obviou sly a dio tic lamprophyre , and in several t cu the of a an respects , more par i larly in presence qu rtz as u u t c f ndo btedly primary ingredien , is distin t rom the typical ar the s of all u camptonites, which e among most ba ic igneo s * k . a a as s b ut is roc s It might perhaps be reg rded as b ic Voge ite , better assigned to the group of Spessartites which Ros enbu sch has established for vogesitic lamprophyres in w hich plagioclase is the a f t a s S s of princip l elspar . Wi h the l mprophyre ( pessartite ) the ‘ Spessart as described by Goller it is almost completely id enticaH

Dr. M of E has x ackie, lgin , prepared an e tensive and very interesting series of chemical analyses which inclu de several rocks f t s f u s of rom hi area . They will be o nd in the Transaction the

E bu G ca S . I P 1 901 . F din rgh eologi l ociety , Vol VII , art I , rom

w e t . these ake the liberty of qu oting the following (I to VIII ) . For a full discussion of their hearin gs on many important questions

u u t d " in theoretical geology , the original papers sho ld be cons l e "

1 00 33 1 000 1 1 00 249

I. Ben Rinnes Granite. II. Granite ein Crai e l achie Brid ite v , g l ge. III . Gran ein Fid d ich Brid e. IV. Ruthrie re Granite A er our v , g (g y) , b l . “ F ett . S . The Tra D es of the Or ne s. Trans . Ro . Vol . i l , J p yk k y y xxx x . Goll er Erw. Die Lam ro h r an e d es end i hen Vors es f , p p y g g l c p sart. Neues Jahrb uch fur Minera o ie Bei a e Band vi . 485 l g , l g . p

Mackie W. M.A. M.D. Sevent Chemi ca Ana ses of x , , l ly Rocks (chiefly from the

Ed in. Geo . 01. iii Mora area . Trans . . Soc . Pt i. ) l , v , . p . 33. On erences of Composition between the Central and Marginal Portions of Granitic

Veins T ns . Edin. Geo . Soc Vol . iii. Pt . i. . 98 . ra l v , p . 44 Exp lanation of Sheet 85.

VIII .

58 44 540 9

9 9 8 8 1 00 22 1 00 07 — — V. Netherl Diorite eri her of os s VI . Netherl Diorite nea er centre. y —p p y b . r VII. Netherl Diorite centre of oss VIII. Diorite and aleith. y b . ,

. THE EARLIE F T II R ( OLIA ED) IGNEOUS BOOKS .

The second group of igneou s rocks represented in this area is obviou sly prior to part at leas t of the earth movements which have

ff c . a ected the region , and this is refle ted in their structure They

are more or less foliated and altered in their mineral constitution . now c i of c The acid rocks are in the ond tion augen gneisses, the basi

principally hornblendic schists . G u c a a f m rey a gen gneisses, whi h h ve pparently been developed ro r u a t s ccu of po phyritic m scovite gr ni e , o r in the immediate vicinity s m l s to u of Keith , and also at localities o e mi e the so th and north

. a hacoid s of a w f m s it Large elliptic l p pe rly hite elspar, someti e s w C i lie a fi t x ho ing arlsbad tw nning , in nely gneissose ma ri

of u v t and a u t uar f . consisting m sco ite , bio ite, gr n li ic q tz and elspar C a ast u u f at cl ic str ct res are very highly developed, the elspar of the phacoid s (which is in large part microcline) is much broken and shattered and injected with veins of finely granulitic

material . The basic foliated igneou s mass es belonging to this earlier series f u - of are ound principally in the so th east corner the sheet , and are x the B c t f the well e posed in the sections on la kwa er, a tributary o

Deveron . s di s They are gabbro , epi orite , hornblende schists and t n b ut a serpen i es , vary in char cter a good deal , some showin g a more complete reconstruction than others in which the original t r of e are l struc u e ign ous rocks sti l well preserved . A r ma a d the a mong the less alte ed types y be inst nce g bbro , one i t of B a at x s m in of m le nor h l ckwater Lodge, the e treme outh arg of u l i a and the sheet , which consists brown , t rbid schil er sed di llage Are 45 Petrography of the a .

F uctu s a basic plagioclase felspar . laser str re is vi ible in the h nd s c m c s a a of a pe i en , as the rock is ro sed by p rallel stre ks d rk green the t u tu c s t a hornblende . Under the microscope s r c re is in pla e h t ut b ut for the s a t of a normal gabbro w itho olivine , mo t p r the diallage is pas sing into a pale green amphibole which form s mas ses of u m s the c t of w c of the a fibro s pris , in en re hi h more or less origin l s a a ft the f s a pyrox ene rem ains . Thi di ll ge is o en broken , el p r h w d ue to s s u an d c i s ows a superinduced t inning pre re , is be om ng ran u li A a w a s m t m s tis ed . d rk bro n origin l hornblende o e i e g - su u th i a b ut the am is of n ew f at rro nds e d all ge , green phibole orm ion , and ma s to d at u w s f the a t n y be een ra i e o t ard rom di llage , penetra i g

the su rrounding felspar . A section of a specim en taken along the outcrop of this mass a little further to the north show s that the schillerised diallage is c t t a c m a t here hanged en irely in o green hornblende in l rge , o p c m as s of u a ut s c s u us a s of u es irreg l r o line , en lo ing n mero gr in opaq e x f s a s are c a s a u t c the a iron o ide . The el p r o r ely gr n li i , origin l t s f s ma structure of the gabbro being obliterated . In hi el par s ll h a tt t t ragged prism s of hornblende lie s cattered . T ere is li le bio i e

t b ut u c f at a s u tu . and epido e , no prono n ed oli ion or p rallel tr c re The

rock is an epidiorite . t i a f Associated w ith this gabbro here s mass o serpentine . In section it has very m u ch the appearance of having resu lted f the c m s t of x as the c a u a att c rom de o po i ion pyro ene , re t ng l r l i e u u m a ma str ct re is w ell arked . The origin l rock y have been a x t pyro eni e . At Crai d orn e fu th t - ast a the s a utc t g y, r er nor h e long me o rop , here i t w c t s m t f s a diallage peridoti e hi h presen s o e poin s o interest . The c c s st c a of an d a a the f m ro k on i s prin ip lly olivine di ll ge , or er in rou nded mas s es weathering into yellow green s erp entine which is u m x covered wi th a meshw ork of d sty agnetite . The pyro ene is a m st c u ss w t f t a am at and um a l o olo rle , i h a per ec pl ty l in ion inn er ble m u a su s c it a t a u and in te d rk enclo re whi h render lmos op q e , are w Occas a a m m dispos ed in at leas t t o s eries . ion lly s all as s of a a w t at s cl su s of the u sua t di ll ge , i h brown , pl y chiller en o re l ype , f u u th t h orms a centre s rro nded by e paler varie y . T ere is no lustre m tt itic st uctu b u t the a a u c o ling or poikil r re , di ll ge is m h broken m t u u and bent . Tre oli e is ab ndant in colo rles s prisms which su u an d t at the c u t s of a an d as rro nd pene r e l s er olivine gr ins , p s in w st a s t u the at s of a i inding re m hro gh broken pl e diall ge . It s often f f su s ma w t u st a t ree rom enclo re , or y be filled i h d y m gneti e . E t has at the x of viden ly it been developed e p ense olivine , or

a a t a f a a . c t s f perh ps p r ly lso rom di ll ge The rock on ain no elspar . A a w a st c u c t is a very p le yello , lmo olo rless hlori e rather plentifu l t of the c a a a ingredien ro k , and ppe rs to h ve resulted from the * weathering of the diallage . A somewhat more advanced stage of metam orphism has been c the as c B ac w at a A w B rea hed by b i sills on the l k er , bove rd ell ridge . They are represented in the collection of s lides by 1 788 horn blende

’ Patton H. B. Ser entin und Am hi o Gesteine von Marien ad . Tschermak M n , p p b l b s i .

eil V l . ix . . 1 1 1 . Petrog. Mitth ., o p - 46 Explana tion of Sheet 85.

s t r t c 9548 and rock , schisto e , wi h large porphy i i hornblendes 9595 n w t , hor blende schists ith a little epido e and decomposing f a t - t n -out of elsp r . The las of these is fine grained wi h draw eyes s an d u m a hornblende resembling phenocryst , wo ld see to h ve been an au t of originally gite porphyrite . In these rocks no race original u u tu a w t x c of t t igneo s str c res rem ins , i h the e eption hese indica ions of t u u porphyri ic str ct re . On B wa 300 s the Ar the lack ter , yard above bridge at dwell, there a i t of a t is hornblende sch st filled wi h little oval lenticles c lci e , which

ad e out u u a a a . re ily w ather , giving the rock a p miceo s ppe r nce The calcite s eem s to have been present before the production of the f at as a u the s ts of t s a t is w oli ion , ro nd po hi miner l here al ays a border of hornblende an d biotite w hich appear t o be pu shin g in a s n t at cal t uc as the s a w rd , pe e r ing the ci e , m h hornblende in he red n t u th f gabbros ca be seen to spread hro gh e elspar . The calcite f s of c ta w t few t of f u orm a mosaic rys lline grains , i h races ract re or

f . x of t s c t c of f fin e de ormation The matri his his onsists a oliated, a t of t t f w t gr ined aggrega e hornblende , bio i e , and plagioclase elspar , i h n u It a a much magnet it e a d finely gran lar epidote . may h ve been fine- u il b ut the of the grained , vesic lar , basic s l , appearance rock suggests at once the possibility that it is a contemporaneou s

lava.

R r EDIMEN AMORPHIC OC S o S AR ORIGIN . III . MET K T Y

Metamorphic rocks of s edimentary origin occupy by far the rt - st t larges t portion of this sheet . In the no h we here is a large f ua cac u s t t a u t c area o q rtzose and mi eo s schist , wi h hin flaggy gr n li i

s M s . u can u t gnei ses ( oine schist ) In these , tho gh there be no do b s f t u t m atu all t a of elastic t u u a a . o heir l i ate n re , r ce s r ct res has di ppe red An account of the m icroscopic characters of this group of rocks wi ll be

the Ex a at of S t 75 . 35 and 36. found in pl n ion hee , pp in ll ch s t a u t f s a t At Ball da o a zoi i e gr n li e orm band in his series . a fine- u t c s w a a f The rock is grained, gran li i gneis , ith good de l o s a s s u f ml di s t c biotite in m ll cale rather ni or y persed, so tha the ro k s t is grey with paler and darker streaks . In thi here is a light

d a u f of . coloure band , with well m rked lentic lar olia biotite The micros cope shows that the principal components are quartz and u e w t a felspar in ro nded or interlocking grains , mingl d i h sm ll

of t c a u . irregular scales bioti e , whi h give it parallel struct re The t u w t a b ut u felspar is par ly nt inned or hoclase or lbite , incl des also u of s n c c a considerable amo nt poly y theti crystals, whi h sometimes of lam ellee show two sets intercrossing , and are partly oligoclase , G partly more basic varieties . arnet is present in crystals up to c and in i t 2 mm . a ross , , addition , z rcon , apatite , epidote , zoisi e , c magnetite , and a reddish , pleo hroic sphene . - r l not h The zoisite is in lath shaped c ystals, which , whi e hig ly hi f u - n idiomorp c , o ten show bl ntly pointed terminations and a gular

ct a fa . r t cross se ions, which are bounded by cryst lline ces The c ys als the Area 47 Petrograp hy of .

are f f u t a a a f rom o r to ten imes s long as bro d , h ve a per ect longi t s f tu s s tudinal cleavage and numerous ran verse rac re . In polari ed u - u u s a x light they give the us al dark bl e colo rs , tr ight e tinction , and ca A ex hibit longitudinal stripes which re ll polysynthetic twinning . w a m st c u s s t c a pale yello , l o olo rle epido e is ommon also in sm ll ,

u a s f u u s a t . irreg lar gr in , o ten s rro nded by zoi ite in p rallel grow h The

‘ ' t c a s are ma a f 5 1 2 mm . w to zoisi e ryst l s ll , r nging rom by do n m ut ra u s the a a a of the f s an d ua in e g n le , ver ge di meter el par q rtz

' ' 2 to 3 mm . ta a the a u a t being In cer in b nds zoisite is b nd n , in c t and ft to a t t t m others s an y, it is o en be rem rked ha in i ately a w m a m u t of ca t w ssociated ith it there is a very s ll a o n lci e , hich

elsewhere is practically absent from the rock . Whether the zoisite is to be attributed to the effects of m echanical s a c c a to the ac ac of us he ring on basi plagio l se , or cont t tion igneo u a s a c c u a ul t is u a t s intr sive m s es on al areo s gr n i e , not q ite cle r in hi cas it w t a f it s x t to the Ben R e , as ill be seen h t , rom pro imi y innes

a t i c t a u u rt of . s gr ni e , ev den e migh be dd ced in s ppo either view The e m m c s s c s of t u minerals are by no eans co mon a ces orie in ro k his gro p , b ut they have been m et w ith in Ross-shire and Inverness-shire

Mr Gu Mr H and M r. G t by . nn , . orne , ran Wilson , and described by

Mr. th A u R t s for the a 1 1 9 Teall in e nn al epor ye rs 897 (p . 8 8

and 1 899 . As w f c (p . (p ill be seen on re eren e to the c t t is c ta a u t of s l arit w the des rip ions , here a er in mo n imi y bet een w All u s pecimens from idely s eparated localities . are gran lites con t of u t f t t cc a t sis ing q ar z , elspar, and bioti e , wi h a essory g rne , sphene ,

s ut and . But the zircon , iron ore , r ile , epidote , zoisite prevalent t s s an d R s -s ta s w f ype in Inverne o s hire con in hornblende , hich is o ten m c t w u s of ua t an d f s a u u i ropoikili ic ith enclos re q r z el p r, a str ct re

s w the s t m a . H w is also ho n by zoi i e in so e c ses ornblende , ho ever , absent from the zoisite granu lite of Sgurr Mor Fannich (Annual

R 1 8 98 . Ballind alloch c a eport , , p The ro k appe rs also to b e a a t a t u sc d _ good de l finer grained h n hose previo sly de ribe ,

c the s t are s m t s 7 to 8 . in whi h zoi i es o e ime mm long . But it is clear that as a group those zoisite granulites have a w ell a ct and the na u of t c defined ch ra er ; , indeed , t re his ro k was r Hinxman f recognised by M . rom its appearance in the hand s c t u the s u s a to pe imen , ho gh zoi ites are m ch too m ll be visible to the naked eye . the c of the Banfishire s c u th In ro ks eries , whi h occ py e eastern a f of s t m a m far s s a a c h l this hee , et morphis is le dv n ed than in the u western gran litic schists . The original elastic s tructures are often t a s a t u ff t c to be r ced, while in ome c ses hey have s ered li tle modifi ation . u the s c s B w t the x - Th s , in e tion on the lack a er , in e treme south east of the s of t corner sheet , band gri or greywacke occu r containing u of u t of f fin ro nded grains q ar z and weathered elspar in a dark , e x c grained matri . There are practi ally no signs of mechanical strain in the qu art z with the ex ception of a lamellar s tru cture visible t c as -d efined a be ween rossed nicols ill , parallel b nds . The matrix t of fine- a ua and s ca consis s gr ined q rtz brown biotite in small les , f f f an d fac a f which , rom their per ect reshness the t th t they requently ua of l pen etrate the q rtz , are new development . The crysta line 4 8 Explanation of Sheet 85

u of v w of of a ac as nat re the ground mass , in ie the absence c t l tic uc u ma r ct the str t res , y be easonably ascribed to contact a ion by c u adja ent intr sive epidiorites . The s ection of a q uartzos e grit from Drummuir shows an t a s c ca essen i lly imilar rock , in whi h somewhat greater modifi tion has A a taken place . lthough quite a grit or greywacke in the h nd c n the u u spe ime , rock shows nder the microscope that the q artz grains have been drawn out an d fractured and wisps of a pale a f a f mica have been developed , prob bly rom an origin l elspathic ingredient . A s till further stage of alteration is seen in sections prepared from the gritty bands which occu r among the phyllites in the

a cutt Mu . t s ru u railw y ing at lben In he e , original clastic st ct res

s m . A fin e s a of u ua t c can eldo be observed mo ic gran lar q r z, rossed a s of a c u u by sc le biotite in parallel series, is the appear n e s ally

. t s u t u presented The mica penetra e the q artz , passing hro gh it

t u for u a s . R u f c wi ho t regard its bo nd rie econstr ction is airly omplete , for it is rare to find that the qu art z shows evidence of mechanical c f u strain or cata lastic ract re . The s ilvery mi caceous phyllit es of this locality consist of mu scovite x f v a f a ft and biotite , intimately mi ed, orming wa y p rallel oli , o en at answeichun scliva e l crossed high angles by an g g . Ch orite is u n c r present , and ro nded gar ets whi h seem to be weathe ing into

. s u u chlorite The other accessorie are r tile , zircon , epidote , to r maline and magnetite . The lim estones of the Banffs hire series have been converted a u a m s - a a into gr n l r, holocrystalline arble , rather coarse gr ined , nd often of a grey colour from the pres ence of disseminated graphitic ‘

us t . a a a few a of a l d They cont in occasion lly sc les pa e yellow, di c d slightly chroic mica , whi h is more abun ant in certain bands it is x u rt to f rm f a ca c where mi ed with q a z o a sort o c lc mi s hist . mi ca c an -d fin d all s The may give the ro k ill e e par el truct ure . a u of u art m c Occasion l ro nded grains q z are the only com on a cessory . s o far the i s - a i There are , as sect ons how , no calc silic tes, and the r

Mr. G a the absence may be due , as r nt Wilson suggests , to original purity of the limestone . The black schist which is s o characteristic a member of the ‘ an flshire s b e st s c a c B eries may be de ribed as a d rk graphiti phyllite , an d in the hand specimen often shows the most minu te pu ckering ‘ anm eiehun schva e. c of ua f u and g g It onsists q rtz, elspar , m scovite , t an d ra u and a — i bio ite , fine g phitic d st ; when co rser gra ned passes - a i int o a graphitic mi—ca schist . In dd tion to the usual accessories of u of , u te this gro p rocks magnetite r tile , tourmaline , iron ores , pyri s, a of a c e f e and v rying amounts c l it , it contains o t n little clear, red, a t rounded g rnets , tremolite or ac inolite , and chlorite . c u n a The hlorite is practically an essential constit ent , bei g lw ays

t a . u f presen in the sections in gre ter or less amount In colo r, orm , c t s and opti al proper ies , it varie a good deal . It is commonly a pale i - n f di a green or grey sh green mi eral , with eeble chroism , the r ys n a to a i r e r vibrati g p rallel the cle vage be ng greyish g e n , pe pendicular to it slightly more yellow (pale yellow green) . Pleochroic halos

50 Imp lantation of Sheet 8 5. for a mica . In many cases in which the two minerals could be u c it to acc rately compared in this respe t , proved have always a slightly lower double refraction than qu artz thou gh in vertical o u f secti ns it invariably gave higher colo rs than elspar , The i n su u t n n mult ple twi ning is u ally obvio s , hi plates , not more tha ' 05 s of as as mm . thick , being sometimes compo ed many ten lamellee but x , others are qu ite simple ; and this e plains the u r t irreg lar behaviou in convergen light . In hot , strong sulphuric

was ac . a acid , the mineral slowly att ked These ch racters indicate that it is a colourless chlorite w ith positive optical character and ' xt a m of u of oblique e inction , ember the gro p which leuchten ” b er it e w n u in g is the best kno example . It generally occ rs small, -f r w of l well o med plates hich lie on the edges smal , rounded or f ua t asa s elliptical lenticles o q r z . The b l ections show rarely any e a u a ut b u t u t ndency to ss me hexagon l o lines, in the cr shed powder r s ix - a u f i a pa ting along a r yed press re figure is o ten v sible , a cta u a a Not f Vertic l sections are re ng l r or l th shaped, in requently in t t i ei a it is parallel grow h wi h biotite , the two hav ng th r b sal a planes in pposition . A very frequent accessory in the black-schist is tremolite or t n a d m s u of actinoli e in elo g te pris , the . dark colo r which is due to

h matt . c c f enclosed grap itic er In mi ros opic section , where ree f c u s rom enclosures , the mineral is olo rles or pale green . Long , d a i a f - ra i t ng prisms , arr nged in eather like aggregates , are some on urfa of the 9594 times visible the s ce hand specimens ( , That the crystals have been developed before the foliation of the c f d s hist may sometimes be proved by their ractured con ition , little “ eyes of qu artz having been formed in the wake of the broken prisms In section 209 1 the crys tals of pale actinolite are a t at w a n filled with d rk graphi ic m ter in vy parallel li es , and the extinction sweeps over the section in u ndulations whi ch correspond u f of c su u f to the p ckering o the lines en lo res . The cr mpling o the u f t a r folia m st be o later origin h n the actinolite c ystals . Fro the u a of t m l t the a - a rnfe m ab nd nce re o i e in c lc silic te ho lses, h a i a s w t the ac —s c s a w ich altern te in th n b nd i h bl k hi t, and the bsence or scarcity of carbonates in the black-s chist itself when the amphi it a tha are to d boles are present , is prob ble t they be ascribe to the of a t a t action contact met morphism , whe her by the e rlier or la er

i rus c the a u . Th nt ive igneous ro ks, on calc reo s phyllites e great susceptibility of this series to contact alterat ion is one of its chief t has e e characteris ics , and b en notic d in the early chapters of this

memoir .

EFFE T or CONTA T T IV. C S C ME AMORPHISM.

Effects of contact metamorphism are to be traced in many parts

‘ of to of t this area, and, owing the variety rock ypes involved , a n of uc ex co siderable diversity prod ts is to be pected. Unfortunately

d e la France et d e s es Co onies T i. 383 has found l , . , p . ) that ' leuchtenbergite is common in the limestones of the Pyrenees where altered by contact ites with ophites and lherz ol . 51 Pctrogmp hy of the Area. the ex pos ures of the contact zone arou nd the Ben Rinnes granite are not b ut A u C a the um us good, near berlo r and r igellachie n ero veins w hich intersect the schists have produced comparatively little

. t is d ue t o s a tu of alteration Tha , perhaps , mostly the resi t nt na re t s u c s c t c s u Ben R s he e q artzose s hists . The his en lo res in the inne granite (9605) an d in the Netherly diorite are baked into a c ac t t f s W at B u H A u at omp t bio i e horn el ; hile l e ill , berlo r , and - - C a ua t f t c s t are u at an d hornfels ed . r igellachie , q r zo elspa hi chis s ind r ed M c i h c f s m t h m s s s Dr. a k e records t e pres en e o illi ani e in t e a e h t the u s affected by the granite veins at t e la ter locality . In igneo rock its elffl akes of biotite and hornfelsed leaflets of s chis t may be t a m a s of the b ut the raced long the rgin veins , there is nothing in wa of c fi at x e t the n of y endomorphi modi c ion , e c p perhaps prese ce Hu t H a u a t the t c c . On sm ll ro nded g rne s in grani i ro k n ill , north w t of A u the a t s u u f a m ts of es berlo r , gr ni e enclose n mero s r g en ua t t an d ua t -f t c -sc ts the ua t t s u st u an d q r zi e q r zo elspa hi his , q r zi e l ro s c ta w the f s a c u a t t a to a a x t rys lline , hile el p thi q r zi es h ve been l rge e ten re-c sta s w t the m t of a m a c st u ctu the ry lli ed , i h develop en os i r re ( — pflaster-s tmctw pavement structure of At N etherl the Bu of R t s s the tt y, on rn o he , be ide li le wooden f t t is the t x s u of the c tact of oo bridge , here bes e po re inner on zone - m s s s t s a w the new er granito dioritic a e o be een ny here in this district . a c u d at c a s - ra i is the f m of a The d rk olo re , r her o r e g ined d orite in or a ac s s the ua s At sill resting on and partly bre king ro q rtzo e s chis ts . s a a s the actua c tact can t . H ever l pl ce l on be inspec ed ere , as every w in s sts a c act ta a s here this sheet , these chi v ry in har er, cer in b nd a ua t s and f th t u c t being m inly q r zo e elspa ic , o hers richer in m s ovi e an d t t . m ua t c m t intq bio i e The ore q r zose be o e conver ed grey, ust us u a t s w a a s th s f actu l ro q r zite , hich h ve moo , hining r re . The f s at c an d m cac u s t t f s more el p hi i eo rocks have yielded bio i e horn else , s st of ua t f a and a c w t t suc a con i ing q r z elsp r, ri h bro n bio i e h s is s c s ha t t fou nd in many contact zones . The e ro k ve los heir schistose st uctu m s s c m an d m a c m tt the r re ore or le o pletely , y be o e spo ed by development of biotite in nodular patches . Under the m icros cope ’ they consist of a mosaic of equ idimens ional grains (Salom on s pavement structure) b ut the large conspicu ou s biotites are poikilitic w t c su c of u a t an d f s a . i h en lo res , prin ipally q r z el p r s t of t uctu the s ac s uc u of Sa m * Thi ype s r re , pongy cont t tr t re lo on , is still better seen in the andalus ite an d cordierite hornfelses are - which alternate with those described . They dark bluis h or c s tu w w t the c t grey ro k , rning bro n when ea hered , in which s his ose t uctu has a t sa a the s r re ne rly en irely di ppe red, while development of t u a a t a a bio ite in ro nded re s gives hem dark spotted appe rance . O a u the c of ccasionally a pink b nd is prod ced by presen e garnet . Under the microscope they prove to consist of ess entially the as the c c M r same minerals ordierite ro ks described by . Teall from the area to the south of this (sheet 75) and from around the Ben ‘ C ua a ranitefi u rt an d f r ch n g Q artz , o hoclase , plagioclase elspars ,

* W Ueb er eini e Einschlu sse m t Sa omon, . g e amor her Gesteine im Tona it. Neues l ‘ p l ah b uch fur Minera o ie vii. Bei a e Band 482 483. J r l g , l g , ress of he Geo o i a Sur o Summar of Pro t c e 0 the nited in d m f r 1 898 . 88 . 1 y g l g l v y U K g o , p 52 Ex lan tion o t p a f Shee 85.

t s t c i e a a u t an d deep brown bio ite, mu covi e, ord erit , nd l si e , garnet c e ts Z r in t are the prin ipal ingr dien . ircon , utile , sagenite in m u e t , a ee i x are ne works gr n spinel , s llimanite, and iron o ides the a are commonest ccessories . The m ore important minerals not irregularly cat c b ut u s tered through the ro k , are distrib ted in bands , of of m f m the in each which one them predo inates , while ro others c it may be t . u s ompletely absen Th s , certain band are rich in biotite an d v u and f musco ite , others in q artz elspar , others in u t t of andal si e or garnet or cordieri e , the contact minerals new d . evelopment being confined to those parts of the rock whi ch had i the c orig nally composition ne essary for their produ ction . This the r * confirms view taken by M . Teall and by Salomon that the f rm f o ation o c ordieri te contact rocks around a granitic intru sion is

FIG 2. Gra hic inter owth of uartz and Cordierite shad ed p r Q ( ) as s een between icol s gord ierite Hornfe s et crossed N . N herl y, Burn of Rothes E i l , lg n. (Section N0 .

di of r a t of s con tioned by the presence ce t in ypes schi ts . The primary f t u n i u oliation h s i d cated, is obsc red by the new d evelopment of i i n r poik l tic (spo gy) st ucture , in which the contact minerals form a at of t r u a f m as e l rge pl es qui e i reg l r or , s en in section , filled with f s enclosu res o the other component . In this way occur a g rnet , i a u an , d t biotite , cord erite , and and l site to a less ex ent mus covite f l . u t and e sp ar The commonest enclos res are quar z , felspar , zircon, n x and . in e iro o ides biotite The cordierite one s ction (9559) is in a inter rt t u a env l gr phic g wi h the q rtz it e ope the two minerals

Sa omon W. Geo o ische und Petro ra hische Stud ien a l , l g g p m Monte Aviolo in eniscb en nt eil d er Adamello r n e. Zel Itali A g pp ts . d er d eutschen Geo G s l. e ell B. 42 (1890) p . 504. 53 P etrograp hy of the Area . through interpenetrating one another have each a single pos ition of

x a see Fi Mr. t e tinction over a consider ble area ( g . Kynas on has described a similar graphic intergrow th of quartz an d felspar in the ‘ Cheviot andesites as a produ ct of contact alteration d This points to the mass having been at one tim e in a plastic or semifu sed condition . It s hould be noted that Salom oni has d escribed glass u s as At s enclos re present in certain contact minerals . the ame t s n of a f a as s c a ime , the pre ervatio the origin l oli tion , de ribed bove , show s that there was never sufficient liqu idity t o allow of mix ing

a a c s a xt . As M r. a m a the t king pl ce to any on ider ble e ent Te ll re rks , cordierite contact rocks have certainly never been in a state of igneou s fus ion and yet there has been a sufficient amount of molecular freedom to admit of groupings of the same type as those occurring in m olten c t The minerals of these rocks call for little remark . The ordieri e is u s an d xc t t at it s s the u ua a s colo rle s not dichroic , e ep h how s l h lo a u is n ot w t s am of a t ro nd zircon . It filled i h tre s sillim ni e needles as the c of the B ac Do . S m a t is fact not a in ro k l k g illi ni e , in , e sily t fi w t c t catt w s s u a t iden i ed i h ertain y . S ered yello i h pri ms are ab nd n the c an d m a a s t s m a b ut in ro k , y, perh p , belong to hi iner l , the ar t c t a a s are u c ss c mm t u ch acteris i divergen ggreg te m h le o on , ho gh a s s nt . a a u t is m st a s of l o pre e The nd l si e in spongy asses , or re m t c a u a s s c u s s tu fa t w the lit le re t ng l r pri m , olo rle , or rning in pink hen ta d t t is d s w the a t polariser is ro te . The bio i e deep red i h bro n , g rne

a wa s t c . Rut ccu s s s pale red , and l y poikili i ile o r in pri m , in net w s s a t an d t w x s in at ork ( geni e) , in ergro n in iron o ide elong ed yellow prisms in the m anner des cribed by Hut chingsfil in the ottrelite f - uart an d f s a f rm a m sa c of slate o Tintagel in Cornwall . Q z el p r o o i - u c s fittin a . s w c is c a ac ro nded , lo ely g gr in s The green pinel hi h h r teristic of the t c tact c s is t m u cordieri e on ro k , presen in s all ro nded

cta a b ut a u a t . c t is st o hedr , is not b nd n The ordieri e mo ly very f b ut s of the s s it is w at t a c u s resh , in ome lide e hering in o mi aceo

a an d t s fa at s its t a . miner l , hi cilit e iden ific tion ' The black-schists and phyllites of the Banfishire s eries in many localities furnish minerals which m ay be regarded as contact act t f u t products . The tremolite and inolite hey req en ly contain the u have already been discus sed in this connection . In neighbo r h of A w the Deveron c s a stauro ood rd ell Inn , on , hiastolite l tes and lite an d andalu s ite s chists are fou nd in some places in contact w ith the intrusive epidiorites an d other rocks of the earlier igneou s suc a wa as t o m for u t t t series , in h y leave no roo do b ha these

Lacroi Minera o ie d e la France at d e ses Co onies T i 521 has record ed the x ( l g l , . . p . ) resence of quartz and cord ierite in graphic intergrowth in certain rocks from the pyrenees . H Notes on on t naston . C tac Metamor hism ar und the Che iot Granite. Trans . ( Ky , p o v

Ed in. Geo . Vol . iii . Pt . i. . 24. l v , p W e er eini e ins l Sa omon . E ch us se metamor her Gesteine im T nalit. Neues I l , U b g p o J ahrb uch fur Minera o ie vii. Bei a e Band 482 483 l g , l g pp . , .

Tea . . H. On the Natura Histor of Cord ierite and its Associates . Proc . " ll , J J l y

A soc. Vol xvi. Pt. 2 . 2 Geol . s , , p 7 - Bonne T. G on Bastite Ser entine and Trocto ite in A erd eenshire with a Note y, p l b , on the roc of the B ac Do . Geo o ica Ma az ine 1885 . 439. k l k g l g l g , , p ' ‘ ~ Hutchin s W. Ma nard . Ou the Occurrence of Ottre ite in the Ph ites of North fl g , y l yll

w . Geo . Ma . Vol . vi . . 214 C orn all l g , p 54 Eap lanation of Sheet 8 5

S 9599 minerals are the result of their contact action . ection , u s u f w i andal site and ta rolite schist , rom contact ith the serpent ne

the B s ca- u , on lackwater, show a mi schist , with m scovite and biotite a tw t — Wi l rge cross ins of s tau rolite up o inch in length , filled th s u of u rt st of s t i enclo res q a z , and cry als pale , ligh ly pleochro c a u s t u u the s u u . i s ndal i e , less n mero s , with ame spongy str ct re It t o be remarked that the micaceou s folia of the rock w ind rou nd the au and u t fa w u ts st rolites do not pass thro gh hem , a ct hich s gges S m that this mineral was of prior developme nt to the foliation . o e of s au s ft w a u t u t the t rolite appear broken and shi ed, hile gr n li ic q ar z ha s ffe t s penetrat ed between the fragments . But the hearing e c s of f i t r ca and a ma the olding n his region a e lo l v riable , as y be appreciated from the des cription s of the gabbro an d epidiorite m s s s of w c f a t a t m as e , ome hi h are highly oli ted, o hers lmos assive , the or showing only the earlier fiaser structu res . The grit on B w has a a f f m lackwater , hich lre dy been mentioned, is ree ro ca u u and a t c s a a taclastic str ct res, no her ro k in the me condition is fin s s a w is w of a a m e chia tolite l te , hich orthy r ther ore detailed t w as f u the m a the descrip ion . It o nd on hill i medi tely behind at A w inn rd ell . t x of t t Fi 3 st of t ma The ma ri his sla e ( g . ) consi s bio ite in s ll , deep a s u ut a of m a brown fl ke , finely divided q artz , and min e d rk grains g n i It is in t at c t a a c a t et te and graphite . h ondi ion gener lly sso i ted wi h fa a a a at uc c a s - a a irly adv nced therm l lter ion , being m h o r er gr ined an d An t more crystalline than is normal in slaty rocks . incipien foliation is produced by the parallel disposition of the scales of a t a w a a w c mic , and by heir ggregation into inding p rallel b nds , hi h

u u the c ast r s . s tt t c rve ro nd hi olite c ystal The rock is po ed , here a u a c the a is s being p ler ro nded p t hes , in which , on whole , mic les u Ot ab ndant and the structure more coars ely crystalline . her are d u e t o tt u s of t t an d m u t and spots li le ro nded nest bio i e scovi e , i f in the cen tre of thes e s ometimes a sm all chiastolite s orming . F ac to ac t s t x a s a a a rom pl e pl e hi ma ri v rie good de l in ch racter , both in coarseness of grain and in the relative proportion of its c u ts . S u it are u onstit en cattered thro gh small, ro nded , almost u s s and t s colo rle garnets , hese are ometimes enclosed in the chias tolite crystals . r of c ia c - a The c ystals h stolite in transverse section are ross sh ped, at s and consist of two arms crossing nearly right angles . Thi is d ue rf o of of to the impe ect devel pment the edges the prism , which acu ae u r are represented by l n bo nded by p ism faces . In some cr c are u t w ystals the not hes in the corner deep , in others q i e shallo - s ee Fi . re a are d ue t ( g The entrant ngles not to winning , as u f xt t the sections have a ni orm e inction hroughou t . In the centre of t a u usu i these crys als there is dark core s ch as is al in ch astolite , - a a f f th lozenge sh ped in section, the edges being par llel to the aces o e of c s u prism . It consists chiastolite , en lo ing fine graphitic d st . This material bears no resemblance to the matrix of the slate it is an d uffic t finer grained, contains little biotite , is s iently ransparent f th to give the optical characters o chiastolite . From e corners of i w l n s of m a t u to th s core , narro i e si il r charac er pass o twards the 55 Petrograp hy of the Area .

i n f s notches the corners o the prism , and in many crystal these a n ec i the tu t l e n are be ng filled up with same rbid chias olite , only in i t the z of the r th s here is more mica, and si e enclosu es is greater, s corre ponding with that of the materials of the matrix of the slate . In this way the imperfect edges of the prism are being healed up b a th of y grow impure material . E i t the s of sm fa as was t d out v den ly centre the pri ces , poin e by R ‘" ohrbach in describing similar crystals in a rock from Ven ez uelaf utw m w are ft grow o ards ore rapidly than do the edges , hich le

FIG. 3 . Chiasto ite in Chiastiolit e S ate Ard we Inn Banils hirc . l l ll , (Section No.

The cr sta s s how the cros s -sha ed t rans erse section w ith the im erfect corners y l p v , p The s ma round c ar cr sta s are being filled in w ith impure material . ll le y l garnet ; an irreg ular mass of quartz is partly enveloped in the chiastolite

' an d f s . A u a m st t behind orm depres ions p re chi stolite , al o en irely f f u s at the c t of the fa s the ree rom enclos re , g hers on en res ce re- t a t a s u w t u mat a B "l” who en r n ngle are filled p i h imp re eri l , ecke , ’ c R ac ex lanation com ares t m of wt w ac epts ohrb h s p , p his ethod gro h ith “ t a of the u - as u t w m u of s t h t ho r gl s a gi es , in hich olec les ligh ly different optical properties grou p themselves on different faces of the c t ma f m an d crys tal . The hias olite y be said to grow in skeleton or at t o a th at a l er period h ve e interstices of the s keleton filled up . That this is a featu re of the whole life history of a crys tal is show n a ia as u w f m c the by the r d te spokes which p s o t ards ro the , entre to

Rohr ach C . E. M . e er d ie Chiastolith enannte Varietat d es And a usit . Zelts . b , U b g l d d ent. Geo . Ges e . Vol . i . . 632. er l ll , xxx x p ' Bec e F. e er Chiastolith . Tschermak s Min. Pet . Mittheil Vol . iii. " k , U b , x p 256. 5 6 Exp lanation of Sheet 85.

s th are the s t t ac of depression on e surface . They per is ent r es the ot B a d n ches in the corners of the prism . ecke reg r s the central u f of the s enclos re as the trace of the terminal aces cry tal , on which w he suppos es a tu rbid chiastolite also to be deposited . Were gro th to u t t u ac of contin e ill the skeleton is comple ely filled p , e h corner u u s t t a the prism wo ld show a rectang lar dark po , like h t in the and w , t , centre and connected wi h it by narrow lines like it ( ith edges parallel to the surfaces of the crys tal ; and this type of * as n of c a Sed erholm chi tolite is well k own . To this variety hi stolite of Malt it has given the name es e. Other proofs of contact action by the intru sive s heet s in this c are a t f s s t u vi inity , the d rk bioti e horn el e in o which the imp re shales above Ardw ell Bridge have been converted in immediate t con act with the epidiorites (hornblende s chists) . The calcareou s layers intercalated in the black-schis ts in s everal c a t to ca c- cat - f c t pla es have been l ered l sili e horn elses , which onsis ma of t a a act ft a t a u inly tremoli e or p le inolite , o en d rk wi h b ndant a S s w a f of t u c gr phite . ection ere prep red rom rocks his gro p ollected '

Dufitown Tullochallum Fiddich . at and at , on the river They were a an d m a s a s t fine gr ined , in addition to the iner l n med, one ec ion w a s u sho ed calcite , a p le yellow biotite , epidote, zoi ite , q artz and a u m a w c w as s s s t colo rless iner l hi h ometime polysynthetic , mo a f t are u of t a prob bly plagioclase elspar . Tha these prod cts herm l t can t u t u it metamorphism here be li tle do bt , ho gh may not be s to t to u m s w t of the of pos ible poin any igneo s as , he her older or the s of t us as s u a aus . newer eries in r ions, indi p t bly the c e Away from the immediate vicmity of any ex posures of intru sive s w are f u u of m ta rock , minerals hich req ent prod cts thermal e morphism occur in many localities s cattered over this sheet . While in some cases there may be doubt to what cau s e there presence is to a as a t a a w d s a t ma be scribed, taken whole hey indic te i e pre d her l It ma t to t of action in this area . y be interes ing give a lis them w r and the localities in hich they a e found .

’ ‘ ’ K AN E . B ha m " M ulb en Allt Bea G Y IT o r , ,i gi ( len ‘ ‘ ‘ Ri s ~Bu of Ald ernie M ortlach Botri hniefi nne ), rn fi fi p

ANDAL S E —M tlach G Tervie Shenwell the B ac w at U IT . or , len , on l k er, ‘ N eth rl Bu of R th s Botri hnie Auchentool f e y ( rn o e ), p , i — RD ER N etherl Bu of R th s . CO I ITE . y ( rn o e )

— ‘ u B h rm ‘ r f l S A ROL E . N ear Keith B of o a Bu o A d ernie T U IT fi rn fl n ,

Auchentool Shenw ell the B ac wat . , on l k er

- CH AS OL E . Near K ith A dw . I T IT e , r ell Inn — S u b m ari n e Netherl C ai achi . y, r gell e

Z Isn ‘E —Ballind alloch in a u it Tullochallum ca c- i i O . ( gr n l e), ( l s l cate h f s orn el ). — ' ann w a. Tullochallum D ufitow n . T o , — NELL . N etherl GREEN SPI y.

ed erholm . G. Om Maltesit en Kias tolitartad andal usitvarietet fran estra S , J ' in and . Geo . Foren. Fd rhand L No. 173 B . 18 . 391 1896. F l l , , p , ’ f Sc n f Six Hed d le s Mineralogy o otla d .

58 Eap lanation of Sheet 85

II CHAPTER VI .

OLD RED SANDS TONE .

The Old Red Sandstone in this sheet covers an area of abou t 36 u a a m t a sq re miles long the northern m argin of the ap . The s rat — belong to tw o divisions of that system Orcadian and Upper neither of w hich is typically developed within the limit s of the

t . are a at f t an u c f t shee They sep r ed rom each o her by n on ormabili y , for the members of the Upper Old Red Sandstone not only rest on the c t of O di a S b ut basal onglomera es the rca n eries , pass on to the c rystalline schis ts . The recent additions to ou r knowledge of the fossil fis hes and a t of the Old Red S of S t a the pl n s andstone co l nd, together with evidence lately obtained regarding the relations of its component s the w a m of H a s member to ne er gr nite asses the ighl nd , have tended t o support the view advocated by Mu rchis on of a three-fold c ass cat of a s st w r an d u s s . l ifi ion th t y em into lo e , middle , pper divi ion The evidence bas ed on the fishes and plants has been reviewed by

Dr. ua an d Mr. Kid ston ct and t at m ts Traq ir respe ively, heir st e en w ill be fou nd in the palaeontological part of the Appendix to this

' m m . u s of the G Su of Ar llshire e oir In the co r e eological rvey gy , ‘ evidence has been recently ot to prove that the lavas and breccias - g the B ac M u t an d R a F ts a c t t s s in l k o n oy l ores , sso iated here wi h hale yielding Psilophyton an d therefore on the horizon of the Lower Old Red Sa t ca c s s of t the nds one vol ni erie Lorne, have been al ered by intru s ion of granite w hich is a continuation of the Ben Cru achan he t s of the G a m ass . On t nor h ide rampi ns, however , pebbles derived from the new er granit e masses and their apophyses are

fou nd in the basal conglomerates of the Orcadian s eries . The latter series s eems therefore to be of younger date than the low er

J . H. division south of the Grampians .

THE ORCADIAN SERIES .

The w hole of the Old Red conglomerate between the river Lossie

n d G w H f s art of M O . a allo s ill , orm p the iddle or rcadian series In the sheet to the north (95) this conglomerate dips towards the north the fish- u t an d u nderlies beds in the b rn of Tyn et . These beds con ain - sh f u a of Achanarras Dr. u an d a fi a na simil r to that ( Traq air) , they are found to the south-west of Tyn et in the face of a rock escarp ment of one of the higher river terraces situated on the west side of

the Spey 650 yards to the north of Dipple . Old Red Sand stone. 59

The Orcadian Series in this sheet is composed almost entirely

of c s m a s . t t f m the Old Red thick, oar e conglo er te The beds ha or S a a c x f m the s andstone re , whi h e tends ro river Lossie to ome miles ’ of the S afiord u a a t at at to the east river pey , nmist ke ble evidence h the t ime when they were laid down the ex is ting coast-line was t at of On sinking at a rate corres ponding o th deposition . the as s of the S f B a s Ca a B at-of-B e t ide river pey , rom r e irn to ne r o ridge , an unconformable j u nction separates the Old Red Sandstone from the H a m am c s and the s u cc ss s w c ighl nd et orphi rock , e ive bed hi h compose the new er formation abut in turn against the underlying ua t and q rtzi es phyllites . The grou nd betw een Braes Cairn and the main road to Fochabers an d Keith is occupied by an area of soft brick-red s andstones w ith a few a of a c m t t a a thin b nds fine pebbly onglo era e , bo h with gener l ° of 1 t sm a -st a to of dip 0 o the north . In a ll hill re m the west the Ca ucc s s s of sa st are s tu t nu irn , s e ive bed nd one een in rn res ing c f m h C to on or ably on the u pturned edges of t e phyllites . lose Braew n er and t o the w s of Pathsid e t are x c y e t , here e ellent x e pos ures of the unconformable j u nction of the Old Red Sandstone . At the at s t t t s are an d s s l ter po , res ing on phylli e , red grey sand tone containing small brecciat ed fragment s of the adj acent metamorphic c s and t s are tu a a s of m at ro k , he e , in rn , overl id by b nd conglo er e f which orm part of the bas al conglomerate to the s outh . The cc at f a ts t s s a are a a u a an d bre i ed r gmen in hi ndstone sh rp and ng l r, ex hibit no s igns of having been s ubjected to the action of running w at b ut a a to a fal f the a ci t s ea- ff and to er , ppe r h ve len rom n en cli ,

have been enclos ed in the sandy m atrix in situ . The grou nd to the north of Altash ris es rapidly t o form the Whiteash H w c t c s of the b asa con lo ill , hi h is en irely ompo ed l g m at w the u of F a s an d its t uta s . s er e , ell seen in b rn och ber rib rie The e s t a s ca w as Dramlachs flow th u ide s re m , lo lly kno n , ro gh very an d w a th deep narro rock gorges . These h ve been eroded in e u a and c m at an d are ft 1 00f t t bo lder cl y onglo er e , o en over ee in dep h , w ith almos t perpendicular s ides only a few feet apart at the bottom of u at is a of the g llies . The conglomer e gener lly fine , a red or u u w t s a an d fa - s a p , s . p r lish colo r i h coar e b nds lse bedded ndy parting “ These s andy beds s how that the conglom erate is inclined to the nort h and north-west w ith an average dip of The pebbles vary f f in size rom fine gravel up to ragm ent s 3 inches in diameter . The material s out of which it has been form ed have been derived from u a of th P the den d tion e Highland metamorphic s eries . ebbles o f u t c a ut tw o- s of the c st u t t q artzi e ompose bo third on it en s , together wi h variou s varieties of mica-s chist and gneis s an d a few w ell-rounded

s of . a t t o t s of t pebble granite In ddi ion he e , pebbles porphyri e frequ ently occur and appear to have form ed pa1 t of a contempo

raneou s ca c . a a a a u m as s vol ni rock They h ve gener lly d rk gro nd , u w c Ia cat c m f thro gh hi h re s tered de o posed crys tals o felspar . A 1 s ac l n Gollach Bu P01 13 similar rock seen in pl e the y rn , between G a d Bu the s t ordon n ckie , in hee to the north . u w u - of S c H In the b rn hich drains the so th west slopes cot h ill, n Culfoldie m of and ear , the pebbles are al ost entirely composed fine 60 Exp lan ation of Sheet 85 .

c s to ca grey sands tone . Their presen e seem indi te that local ithm denu dation of this formation had taken place somewhere w f the limits of the Moray Firth basin at the time of the formation o c at the onglomer e . f For three miles to the s ou th of the Keith road the boundary line o the Old Red Sandstone on the east s ide of the Spey is only an x a as the u a c appro im te one , gro nd is p rtly overed by the large peat u u a mos s of Dou glas sheil and other su perficial acc m l tions . In the Allt Tersie u Scotshill f u t x , j st below armho se , here is an e cellent ex posu re of the u nconform able j u nction between the conglomerate d t a an he Mu t s . c a lben phylli e The onglomer te is very co rse , and for a dis tance of a hundred yards is s een t o res t u pon a very - irregular an d u neven s urface of phyllite schist with quartzose b ands . B t t s x su the f of u an d e ween hi e po re and oot the b rn , also in the S ct at B t -of-B t the s sts an d the u pey se ion oa ridge , bo h chi q artzites s c Old Red Sa as are tained red , indi ating that the ndstone beds

x c a fa t o the u . originally laid down , e tended onsider bly rther so th The boundary line of this formation cross es the Spey valley a tt the t of O t u c t s u the Gerrack li le to nor h r on j n tion , hen wind ro nd ’ M s tu t o the u the a of F a S t o s , and rning so th a little to e st indl y s ea descends into the valley of the Spey a short dis tance t o the north of the G s of R t s w ffs of c at are reen o he , here low cli onglomer e seen in u t t s of th u ar clos e prox imity t o fiaggy q ar zi es . Thi portion e bo nd y ’ is F S t c a ft line very indefinite , indlay s ea being thickly l d with dri and timber . Red Bu a Aulton s id e the t s are c In the rn , ne r , s eep bank omposed of c u a N . 1 0 E . the u red r mbling conglomer te , dipping , and in pper branches of this s tream there are numerous ex posures of deep red a w w s a c O the and purple conglomer te ith yello ndy pat hes . ver dis trict of the Tien dl and no rock appears at the surface 5 b ut farther to t - s s am w s s u of Humb rack s the nor h we t , the tre hich rise o th give s w s a a very good section as far as Braehead . It ho red and at w c are u m ottled purple conglomer e in hi h the stones well ro nded , an d reach as much as a foot in diamet er . Betw een Rothes an d Coleb urn s a powerful fault forms the south f w es t boundary of the Old Red Sandstone ormation . This disloca is tu tw o ts b ut a t o tion never ac ally seen between these poin , ppears f R t a s uc a fau u follow the west sid e of the Glen o o hes . Th t h lt m st ex ist is proved by the fact that the Old Red Sandstone beds in the w a w Littlehau h an d c rail y section belo g are smashed brec iated, and a the w t me often inclined at high ngles to north , hile in heir im diate vicinity metamorphic s chists are seen in a similar broken condi At f of the m a w tion . the oot glen a s all stre m that rises belo the m llb urn afford s s of the c farm of S a a good ection onglomerate . ' to The beds dip N . and appear be intersected by several small f u . t u w f a lts The stones are mos ly well ro nded ith a smooth sur ace , at of a at the are larger the top the section th n bottom , and appear to have been derived from the gneiss and quartzites of the adjacent metamorphic rocks . r of G of R is flat is The upper po tion the len othes very , and u iu and b ut s covered with all v m peat , on its teep eastern slopes Old Red Sand stone. 61

bet ween Birchfield and Coleb u rn s the re are numerous rock ex posu res a f u an d t are t showing b nds o p rple red conglomera e , which ei her f u w c lying flat or gently inclined to the north . The a lt hi h traverses the Glen of Rothes mu st either die ou t or pass into the Old Red If u u s to Sands tone to the north of Coleb u rns . this fa lt contin e it us all a i t f u a the north m t, in prob b li y , orm the bo nd ry line between the upper and m iddle divis ions betw een Cockmuir and Culb ackhillock b ut th is the u s t , ere no evidence on gro nd in uppor of t s V w hi ie . Betw een Coleb urn s an d Gedloch the conglom erate n ow occu pies an area w hich may have formed a small b ay in the coast -line during - s of t . On the s u t i of the w ca thi period deposi ion o h s de hollo , lo lly ” w the Slo Ged loch c ffs of a a kno n as gg , below , steep li rem rk a c act c at w t a as a a are ably h rd omp onglomer e , i h b l brecci , F t s opposed to equ ally steep cliffs of metamorphic rock . rom hi point t o the river Los sie the Old Red Sandstone occupies the low er n h u l At the f t of the Ged loch Bu s lopes by Werdend a d S o g e . oo rn an d tt n m t an d a c a w t t a red mo led co glo era e b nded bre ci , i h hin p rtings of sa st are s st u c f m a a red nd one , een re ing n on or bly on h rd pink u a t t s at the c inthe t ct a u Thomshill is Old q r zi e . Th ro k dis ri ro nd Red conglomerate is inferred from the contents of the drift and the presence of numerou s conglomerate bou lders w hich are scattered the u fac an d a x u of a of over s r e, lso the e pos re a small p tch m hi l At the f of th st conglomerate to the s outh of Tho s l . oot e eep slope which lies betw een the Hillhead wood and the river Lossie t are e a c x u s x - and here s ver l good ro k e pos re , e hibiting deep red u c m at a f to c s w th w - u d p rple onglo er e , v rying rom fine oar e , i ell ro nde t s ones . T ADIAN ERIE —In t s O ca OU LIERS OF ORC S s. hi sheet the r dian s of Old Red Sa s w w as fi st t d divi ion the nd tone hen it r deposi e , mu st have extended very m u ch further t o the south than its pres ent t s is the u m u s ut s c are f u limi . This proved by n ero o lier whi h o nd c all the ma f the t of s to s attered over p , rom vicini y the river Lo sie h the Lower Cabrac . Between the river Loss ie an d the head of Glen Rothes there are two areas of conglomerate an d breccia around Middleton and Hang in fold at the m t at t two ca t g . Th conglo era e hese lo li ies had at one t m t u u s wit the a the is i e been con in o h m in body to north , proved by th h e reddening of t e intervening rocks . On the east side of the Spey fou r ou tliers of the Orcadian s s a m a a s is s u a t erie h ve been pped . The l rge t one it ted o the s outh of the Hil of w a fiat- w a t u l To ie , in bottomed , ooded v lley , hro gh c s of the a t u f th whi h flow one he d rib taries o e river Is la. The rock exp osed along the bank of this stream is a deep-red fine con f tt ’ at t a s o s a s . At Du fitown glomer e, wi h b nd gri y and pebbly nd tone , the western pier of the railw ay viaduct acros s the river Fid dich is f u a a cc c m and s ounded pon co rse , red, bre iated onglo erate , thi small a xt a s s a u the a t a u are may e end hort di t nce p v lley ow rds Little T lloch . ' Near the railway su mmit between Dufitow n and Drumm u ir there is a patch of conglomerate too small to be shown on the one m of inch ap . It is seen in the head a small burn which runs down f S u H c s lwa J rom the ca t ill and lo e to the rai y . . S . G. W. 62 heet 8 5 Exp lanation of S .

f a a u s c In the extreme s ou thern portion o the re nder de ription , tw o small outliers of the Orcadian or middle divis ion of the Old Red Sands tone res t u nconformably upon the schists an d quartzite of the B ffs an hire series . The m ore w esterly of thes e is found immediately east of Craig a at a f Tervie s ut of Ben R an d he d Inn , the he d o Glen , o h innes , occupies an area abou t a third of a m ile in length along both sides of the Tervie Bu are x at rn . The rocks e posed several points along m t its t u s an d c t of c the ain s ream and rib tarie , onsis oarse , u u u u - a cc a c t a u of a t m lt o sly arr nged bre i or onglomera e , m de p l rge sub - u a u of ua c —s t the ang l r and ro nded blocks q rtzite and mi a chis , f a at m c ormer l rgely preponder ing . The conglo erate losely resembles that w hich occu rs along the w es tern an d southern limits of the t u ut w t w c t s s at atc u Tomin o l o lier , i h hi h hi i ol ed p h was no do bt at t one ime connect ed . x t m t xt m t of the C ac ut a The e re e nor hern e re i y abr h o lier , t of w w f u the x a a of t 5 descrip ion hich ill be o nd in e pl n tion shee 7 , a fa s w t m ts of s m a its u n m lso ll i hin the li i thi p , crossing so ther argin a m t f th r n ile o the east o e river D eve o . The area is a very small an d the x u s of c s one , e pos re grey or red in oherent sand tone are

ca . t of t st ccu c f very s nty The only poin in ere is the . o ren e o a bed of t m u s a a s m a t o t at is as at w t con e poraneo l v , i il r h which soci ed i h the u arr Hill Sa s a R A a Q y , . ‘ nd tone ne r hynie in berdeenshire It is d a u c t t ma c as an a t rk p rple amygdaloidal ro k , ha y be des ribed l ered s H ande ite . L . W . .

UPPER OLD RED SANDSTONE .

c a the E s This division , whi h is l rgely developed in lgin di trict to the t ccu s a few s ua the m a . nor h , only o pie q re miles in p In the t -w st c of the s t is a a w u - nor h e orner heet here n rro , irreg larly shaped h u an u a c a a ut 1 5 stripe of t e pper beds . In old q rry near Lo h ber bo - - f t of s w a t c s a st has w u . ee reddi h bro n, h rd , hi k bedded nd one been ro ght This sand stone contains fragments of qu artzite and m ica-schist s imilar to thos e of the m etamorphic series immediately t o the s ut . the is x the s of a c at o h Wherever rock e posed, pre ence onglomer e breccia indicates depos ition in a b ay of the ancient coast -line n n d D u F t s f t betw een Lauren ceto a r m . rom hi arm o the point ' ' w Rafiord t formation asses ou t of the t the belo where his p shee ,

’ bou ndary line has been drawn along the foot of the hard featu re h u m am c c produ ced by t e nderlying et orphi ro ks . the s u - ast of u B a Bu u To o th e T lloch and near the l ck rn , the colo r of the drift and the pres ence of som e blocks of red and grey sand stone su ggested the possibility of a concealed outlier of Upper ,

Old Red S s . 1 880 sm a a and tone In a ll tri l opening was made , and was ac t of f t u the rock re hed at a dep h five ee , very m ch jointed and

w e . is a some hat brok n This sandstone rather hard, coarse gr ined , n d a u f to a v ries in colo r rom grey light pink . It contains a few a s and s a yellow clay g ll , the bed ppear to be horizontal. A considerable area of these upper strata is found in the valley of s s H of Mulun d Wan ie is the Lo ie between the ills y and The g , and it 3 Old Red Sand stone. 6 very probable that the s ame beds lie beneath the large alluvial hau gh f D st a w s o allas between these two hills . In a small re m hich flow the s a F C u c of D as are a down hill ide bove the ree h r h all , there sever l A s m a c at ex posures of decomposing conglomerate . i il r onglomer e t o s the mm at w the is be een in river Lossie i edi ely belo village , and red s andstone w ith green clay galls and conglom erate in the burn at Au s c at of t ca t all chne s . The ro k each hese three lo li ies in proba b ility repres ents the basal beds of the Upper Old Red Sandstone

s . a ua t o the w t of Da as w w serie In q rry es ll Lodge , hite, yello , and reddish thick-bedded s ands tones containing clay galls are seen - Hatt the t o the t w . a ua dipping nor h est In nother q rry beside on , face show s 40 feet of thick bedded yellow an d white s ands tone w ith

t t to the st . S a s w w the a gen le inclina ion we ever l mile lo er do n , on ft s of the s s an d at the of the st a u um le ide river Lo ie, edge ream ll vi w it u s 300-f c t u t is a sm a tc here to che the eet on o r line , here ll pa h

of sa st a ut 1 2 f t t st ua t t . nd one bo ee in leng h , re ing on q r zi e To the north-east of Rosehill there is a sm all area of conglomerate f is x a ff t f and sandstone . The ormer e tremely h rd and very di eren rom h It is s of t e conglomerate of Glen Rothes an d the Spey . compo ed - su b a u a and u c s of ss ua t t an d u t . ng l r ro nded pie e gnei , q r zi e q ar z at x xc ha an d s m a a m a The m ri is e eedingly rd , in o e pl ces l ost n the s uth s f th s c m t t is a s a quartzite . O o ide o i onglo era e here m ll at of a w t sa s w c c ta fish- m ai s p ch fine hi e nd tone hi h on ins re n . Although the actu al junction between the conglomerate an d the a x f is u s asa s ndstone is not e posed , the ormer do btle s the b l portion of the a t l t er . A narrow tongu e of Upper Old Red Sandstone ext ends along the north s ide of the Black Bu rn from Plu scard en Abbey t o the northern f t t the of the A th s a t edge o his s hee . To north bbey e nds ones are a c a an d fa s — an d c ta s of u a t t h rd, o rse , l e bedded, on in pebble q r zi e . The quarry on the north s ide of the road near the bridge of Torriest on has s and w t a st s been opened in fine yellowi h hi e s nd one . These are c the s st f a an d t s t thi k bedded, yellow and one is very ri ble , bo h pre en a very marked difference to the hard qu artzos e sandstones fou nd h u the and at th f h A hig er p hill e back o t e bbey . u a to s ut of t t H u s B ac Three h ndred y rds the o h Wes er on o e, l k u a a t c of Old Red Sa t is s a a b rn , sm ll pa h nds one een ne r h rd , grey

tam c a . as of t t the s ct me orphi fl gs To the e t Whi e ree , in same di tri , t is a s m a s t an d a s c of ct d c here i il r depo i , in the b en e dire evi en e t o the contrary these tw o sm all outliers are regarded as belonging to u of Old Red Sa t the pper division the nds one . The triangular area of the upper beds indicated on the map to the s of the s and u m r St c ea t river Lo sie , aro nd Long o n ation , ontains ” — w f if u s ca f aat a the well kno n ossil ero lo lity o Sc Cr ig. In the centre of m t u w s the Bu and the s all glen hro gh which flo Longmorn rn , 366 a to the s u - s of Whitewreath s u y rds o th we t , there ri es a ro nded knoll of and w u c m a a w as fine red yello cr mbling onglo er te, loc lly kno n the

S caat C . d of the c u t ct an d raig The be ding ro k is q i e distin , is ° at a of 8 f N 2 inclined an ngle in the direction o . 0W . The s ection is u u c u a u of the now very m ch obsc red by the r mbling n t re rock , t of f and u s t f the grow h plants along its ace , by r bbi h sho over rom 64 Exp lanation of Sheel 85 . the cu t a u fish- a n s are ot at the l iv ted gro nd above . Fossil rem i g ” a C b u t u u s . st u raig , they are not very n mero They are mo ab nd nt t o abou t 300 yards higher u p in the bed of the stream an d oppos1 te the u wa a wa a ft an d . nder y r il y bridge , in so , yellow red sandstone The foss ils are very brittle and the greatest care is requ ired to as t f m the i n preserve them , hey have often to be removed ro rock s f w a f a m t s . Dr s u m ll r g en . Traqu air has kindly pplied the ollo ing lis t of fos s ils obtained from this well-known locality m Psa mosteus u tul u Tra uair. p s at s . q

Cosmacanthu s M l lm A assiz . a co soni . g B A iz othriolepis major . gass . ‘ Con chod u s ostreiformi M o s . C y. H c u n ob ilis simu s . A assiz olopty hi s g , t us A ass z l gigan e . g i

d ecb ratu s . Eichwal d.

Pol l cod u yp o s s p .

For 200 d u of a a the ar yar s to the so th the r ilw y bridge , beds e

to N . 30 . at low a c inclined W a ngle . This section is omposed of s of a c a and t a band fine conglomer te , with o rse deep red , ligh and d rk - w s a s . S of the s a s s are and yello ndstone ome nd tone ripple marked , the contrasting colou rs of the different bands produce a very fine At th f t f u effect . e end o this section here is a gap o abo t 200 yards before the deep red conglom erate of the Orcadian grou p a s . J . S . G. ppear W .

Mr. has fu a of f s Taylor, Lhanbryde , rnished note the ossil collected by him in recent years from the following localities in the Old Red Sa f m u Bu H u Upper ndstone ro q arry near rgie o se , in the t - s t c of s Psafmnn ostens Ta lori Bothriole is nor h we orner the heet , y , p ma or 2 f Ha t u a Dallas Holo t e/i ins nobiliss imns j ; ( ) rom t on Q arry, ne r , p y ; 3 fr Pluscard en A ua Holo t chius nobilissimus 4 ( ) om bbey Q rry , p y ; ( ) Torrieston u a ut a f-a-m t of Plu s card en Holo t ehias Q arry , bo h l ile eas , p y ’

i simns an d Bothr o e i f m t Mr. a s t at s nobil s i l p s rag en . T ylor de ermin ion

r a ua . have been confirmed by D . Tr q ir The horizons in the Upper Old Red Sands tone to which these fossils probably belong will be discu ss ed in the memoir of the Elgin t J H district (s hee . .

66 Exp lanation of Sheet 85

Further confirmation of the ice-carry from a centre of dispersion i o r t - s f u the of ly ng t the no th and nor h we t , is o nd in blocks con glomerate and sandstone distribu ted over the northern part of the a are . Nu merou s large boulders of the peculiar conglomerate-breccia of Stonew ells - of E are f u c t o u , north east lgin , o nd onsiderably the so th — east of that locality ; two erratic blocks the one of deep red sand the of w stone , other yellow with green galls , both hich have been derived from the upper Old Red Sandstone strata of the Findhorn a — s at M f-a- of Breachr v lley are een the eikle Cairn, hal mile west y, Dallas 3 and similar evidence of the sou th -easterly movement is afforded by the occurrence at Clackm arras and Fochabers Junction of u of m a t u ch of bo lders conglo er te , grani e , and the bl e erty rock

Stotfield E . On the fu of the S and lgin rther side pey , an easterly carry along the northern margin of this area is in dicated by the s - a of Mu S of u of pre ence , " mile e st lben tation , bo lders red sandstone s imilar to that of Stotfield Links ; and of blocks of conglomerate

fu t the of . J . . G . still rther o east in the direction Keith S . W

Dr. M of E out ackie , lgin , was the first to point a local dispersion of boulders of the Netherly diorite over the area “ * u of R s an d B n B c f between the b rn othe e Rinnes . lo ks o this characteristic rock have been traced southwards across the Spey at E far - -Bat an d th s f B n R Wester lchies as as Tom na e lopes o e innes . These may have been dropped in their present position by a marginal lobe of ice flowing from the large glacier to the north throu gh the “ t the a of Hu H S hollow hat lies to e st the nt ill down to the pey, at a time when the lower grou nd had been left bare by the retreat c of the Strathspey gla ier . Y— a BOULDER CLA . This deposit is well developed over the gre ter of a and - to the part the are , especially on the higher hill slopes t - of the S the s cut the nor h west pey valley, where ravine by head waters of the streams flowing into the Spey and Los sie show t he f boulder clay to be o great thickn ess . u f u It varies in character with the nat—re o the nderlying rocks . Over the area occupied by the quartz schists and flagstones it is a a a but a the ut of s omewh t incoherent , yellow , s ndy clay , long o crop the black-s chists and lim estones it becomes dark in colou r an d very argillaceou s ; whil e over the areas occupied by the Old Red t at the ut Sands one str a, and in region lying immediately to the so h - of t u fu of f m and south east hem , it is red in colo r and ll rag ents c Interstratified of these sedim entary ro ks . sands and gravels are b ut at Drumna rain u not common , may be seen g , one mile so th - s south east of Ballind alloch Station . The tones imbedded in the t sub-a u c s of b ut boulder clay are mos ly ng lar blo k local origin , in the w estern part of the area there are also many rounded bou lders f m n h and of granite , probably derived rom asses lying to the ort - north west . u of Al lt A f B of C The present co rse the rder , rom the ridge ally the S ff n of the to its junction with pey, a ords an interesting sectio a - i deposits filling up pre glacial valley . The stream is now flow ng

Ed in Geo . Soc Vol VIII . l . .

67 ‘ Glacial Drift and Recent Dep osits . a of the c t has for long the extrem e northern side an ien valley , and - its left hand bank the original rocky wall of the glen . The southern or right-hand bank gives a clean-cut s ection of from 1 00 u to 1 40 feet of fluvial and glacial depos its . The pper portion s s s of 20- 35 f t of a t a an d s con i t ee l mina ed s nd andy clay , showing u cu t- w t of s obliq e and rren bedding , and i h occasional bands pebble s is ucc 1 00—140 f t of s u near the base . Thi s eeded by ee andy bo lder c a c ta a a u a of u an d l y , on ining l rge ng l r blocks q artzite rounded

P . . H . granit e boulders . ( late L W x of few - s the w of With the e ception a bare hill top , hole the grou nd to the west of the Spey an d north of Knockando is covered w t u c a ft t s i h s perfi i l dri deposi . Red u -c a a a u of a f m bo lder l y , l rgely m de p materi ls derived ro the Old Red Sa t o the t -w the s of ndstone nor h est, covers slope the H is a of f b ut M nau ht H . A t f the E o g y ill por ion o ildon ill cle r dri t , the long ridge that lies between the Black Burn an d the river - hi c t s of Loss ie is again com pletely drift covered . T k deposi - bou lder clay occu py the ground on the south side of this river . The scars cut by the Lennox Burn s how as mu ch as 1 35 feet of st wn u —c a s t s s t am at and a ony bro bo lder l y , ome ime ligh ly l in ed , ne r the head of the burn from 20 to 60 feet of a greyish or yellow x s Mannoch H ar at clay is e po ed . The ills e deeply sw hed in m a s ts c to the w of t s to c si il r depo i , whi h est hi point seem rea h an even great er thicknes s ; 1 00 feet of gravelly and sandy drift being at the a of Allt A an d a 200 f t at the c seen he d the rder , ne rly ee Lo h f th wla Num u t s cut u of R o e Co tt . ero s sec ion by the b rn othes show that the yellow ish -brow n boulder-clay which fills the lower f part o the glen mus t have a thicknes s of at least 1 50 feet . - of S a s the The right hand bank the river pey , ne rly oppo ite village of R t f c iff 200 f t of u - a o hes , is ormed by a l , eet in heigh , bo lder cl y ca t s a and a w of c pped wi h nd gr vel . The lo est part the se tion s s a - c u - c a a di play deep red, very ompact , bo lder clay , ont ining l rge at u u a c s a c s of stri ed bo lders . To this s cceeds on ider ble thi knes compact greyish-brown clay w ith reddish patches an d lenticu lar - - a s of fa and a . Mid wa u ff an d b nd lse bedded sand gr vel y p the cli , a a t u c f ma u -c a t f w pp ren ly resting n on or bly on this bo lder l y , here ollo s a at t c s of u a - s a and a f m a t gre hi knes reg l rly bedded nd gr vel , or ing p r of the high-level alluvial terrace which ex tends from near Aikenw ay of Arndill P to the Wood y. ( late III .) The dis tribution and character of the boulder-clay in the vicinity of Rothes affords further eviden ce of the south -eas terly movement f the t N - f u of o ice over his region . o red bou lder clay is o nd west G of R s and s t the len othe , the reddened depo i s only begin to appear at variou s distances up to a mile to the east of the Old Red Sand u a u n d s tone bo nd ry . The gro nd between the Wood of Dun d urcas a ’ ‘ F a Seat is cu c s s b ut w indl y s oc pied by s hi to e rocks , is covered ith compact red boulder-clay which must have come from the north Red u - a u at west. bo lder clay is lso spread over the low gro nd the f Ben A a and u in Arn ill far foot o ig n , is seen in the b rn d y wood not from the top of the hill. of Aultd er Bu F ff a The lower part the g rn , near ochabers , a ords 68 Exp lanation of S heet 8 5. — very fine example of a pre glacial valley in the course of being re- x of i e cavated by the present stream . The phenomena eros on at a a seen this loc lity are very interesting , and are described l ter t s c a on in hi h pter . The conglomerate area of the Scotch and Gallows Hills is mostly f d b ut u - covered with a gravelly dri t eposit , the so th easterly move - ment of the ice has filled the valley of the Forgie Burn w ith deep red drift containin g blocks of red sandstone identical with the rock in l h h‘ A rif place between Braes Cairn and Au t as . good d t section ' ’ is afiord ed u to of H M red by the b rn the north errick s oss , showing bou lder-clay passing upwards into dark-brown clay capped with s A f m t d i - and and gravel . nother good section o co pac re d sh brown c a i s an d s t d u at Rosarie 2 - l y with pol hed tria e bo lders is seen , é miles of An west Keith . analysis of the fragments contained in the clay s at 68 t ua 2 . howed th per cen . were q rtzite ; 0 per cent gneiss and - t 4 4 a 4 mica schis per cent . phyllites ; per cent . gr nite and per c . ld d ent O Re Sandstone . To the north-east of the granite area of Ben Rinnes the drift is c of t a t o the ut of largely omposed grani e w ste , while so h Keith the cou ntry is covered with a stiff dark- grey an d b rown boulder-clay ; facts which indicate that this part of the area lies outside the u of the Mo - infl ence ray ice sheet , and has been overspread with ice ' - c f m S u . a s e Dufitown oming ro the o th west The v lley b tween , C ors emaul u of the , and the so thern margin map are more or less t c w u - of a m hickly overed ith bo lder clay si ilar character, which s a t n R L nemore reache considerable dep h in Gle innes , and at y c c th attains a thi kness of 1 00 feet . Its local chara ter varies with e n u of u b ut u u a a s ff at re the nderlying rocks , it is s ally d rk ti clay, - J . S . G. . varying in colour between redd ish brown and grey . W SANDS AND GRAVEL —A c x t of and s . onsiderable e ten sands ' gravels of fiuvio-glacial origin covers the low ground around Rafiord -w t of the and tc ut a as far as in the north es map , stre hes so hw rds B s and B a r s ut othie ri ch . Thes e depos its a e di trib ed over the area of a hr f of m a kamiform either as flat plains gr vel , in the orm s ll ‘ and s a Bu at Rafiord a ridges hillock . In the Gran ry rn the str tified - u -c a On sands and gravels rest upon reddish brown bo lder l y . the north side of the Hill of Mulu ndy the gravels merge into a series of - f the of the B u high level terraces on both sides o valley lackb rn . out of —c a o s and are These terraces are carved the boulder l y sl pe , a in some cases covered with sand and shingle . They are somewh t irregular in disposition and ex tent ; the longest have a gentle inclination to the wes t contrary t o the fall of the present river of an of t e valley , and the highest them reaches elevation a lit l A f above 500 feet . similar series o terraces is seen on both sides of for u of D the the river Lossie two miles to the so th allas , highest of e 800 f which almost r aches eet , while the general inclination is in this case down the valley . A large area immediately to the s outh is occu pied by sand and a kamiform ni gr vel deposits , or possibly morai c in character, that lie t a u M of Bednawinn x n t o of hickly ro nd the oss y, and e te d the head G n w e t - f r le Lossie, s e ping over the moorlands to the nor h west as a

70 Exp lana tion of Sheet 85

1 00 f u of ua t of a u eet , made p nearly eq l hicknesses gr vel , bo lder c t u t he clay , and onglomerate . The su rface wa er r shing down steep f r of the a and slope o the O diequish Hill pou rs over the edge r vine , has carved out of these soft and incoherent materials a remarkable - as s emblage of circular s teep sided. pinnacles or earth pillars .

P at I . .F c a are a a ( l e , rontispie e .) These pill rs inv ri bly capped with c of u t u f a thick overing to gh heathery herbage , and it is to his t r capping that their origin and subsequ ent preservation is due . a th of u u c s The herb ge on e slope above the ravine is neq al thi knes ,

“ and the surface water as it stream s over the edge of the chasm flow s round the thickertu ssocks and “ isolat es them from the su rrou nding

Th , t urf. e portions bared of their grassy covering are rapidly w t the u t at the t t s a a eroded, i h res lt h pro ec ed portion fin lly st nd

out as s t s a of u f. i ola ed pyramid , each with its c pping t r These pillars can be seen in every stage of detachment and isolation f has rom the bank behind, and in those where erosion proceeded fu the and u - u of rthest , gravel bo lder clay rest pon a base con Th a ft glomerate . e wind acting u pon the u pper sandy l yers o en u a u f u t ct ndermines the gr ssy cap ntil it alls , and the npro e ed pillar

s aw . J . G. . wa tes rapidly ay . S W The lam inated s ands described as capping the bou lder-clay in the Allt A f of of fluvio- rder section, orm part a deposit glacial sands and

gravels that occur at s everal points along the valley of the Spey . Above Blacksb oat and Mains of Kird ells they cover a considerable a a u fa of a a rea on the hill side, presenting rolling s r ce ltern te ridge and hollow that m erges along its lower margin into the higher f Furt of fluvio alluvial terraces o the Spey . her traces the terraced glacial deposits are seen along the valley of Knockand o Burn T md w Pri tfi ld the s u between o o and es e . The steep bank on o th of the di a c C u a side stream imme tely below Kno kando h rch , gives of 5 f f w a n fu of the section 7 eet o fine hite s nd . O the rther side u n w C S u w and - a d same b r , belo the ardow choolho se , a ide well m rke com t errace ext ends eastwards towards Knockando Hou se . It is posed mostly of finely laminated clayey sand resting u pon boulder an d s a its t m a m the s of clay , seem long nor hern rgin to ark po ition w A a a small glacial lake occu pying a hollo in the drift . section in roadside quarry near Cardow shows great disturbance in the beds of

s c a . t u at fine sandy ilt and l y They are til ed p high angles , some

a r f c rt . times ne rly ve tical , and o ten violently onto ed The longer axes of the stones that are scattered throu gh the sand are always

parallel t o the beddi ng planes in whatever position these m ay be . The phenomena suggest the action of masses of ice grou nding in H shallow water . L . W . . - —At C a ac Brickfield a at t BRICK CLAY . r igell hie the cl y presen u is - m i wro ght a light brown , la inated , glacial silt , with hor zontal c t of bedding , and ontains hin layers fine sand or very small gravel , u 2 s in a t with occas ional pebbles p to inche di meter . This deposi u 1 8—20 f c of clay is abo t eet thi k . It marks the site of what was a u once a glaci l lochan , and occ pies a shallow depression in the - - ft u f a . At o of dri , abo t hal mile in length one porti n the section , - and x false bedded glacial silt, sand , gravel are e posed , and these

the f J S . G seem to indicate presence o floating ice . . . W . c n i 7 1 Glacial Drift and Re e t Dep os ts .

— t w an MORAINES . There are few locali ies in this region here y regular assemblage of moraines such as mark the track of a local t u a c u of glacier can be observed, ho gh isolated mor ini mo nds a f ft a u s gr velly dri t , o en str tified , are seen in vario places along the

Spey valley . u u s u at Fanmore and Croftind acker a S ch mo nd occ r , short st w and t - of Ballind alloch and the di ance est nor h west , on hillside a Culfoichm ore s r u a con bove , even miles highe p the river ; while sid erable a a the t of the a of the Allt B a re in higher par v lley re c , in ut -w c of the ma w t m c ft the so h est orner p , is covered i h oraini dri s u - s s of the -f re ting upon bo lder clay . The di po ition well ormed m oraines throu ghou t this hollow indicates a movement of the ice - from the north or north wes t . A m a a c m u a a u of w s ll mor ini o nd , lmost entirely m de p ell u f a m t of u t t s i and s ro nded r g en s q ar zi e , ch st , granite , lie on the w a - of C a -an—Tarmachain w the S and the ter parting re g , bet een pey

A at a t of 21 00 f t . f cu t to acc u for von , heigh ee It is di fi l o nt the s of s m b ut at a s m a t po ition thi oraine, the m eri l y have been deposi ed by infra-glacial water in a hollow of the ice-sheet that enveloped th md H e Cro ale ills . Traces of the local glaciation of the C onval Hills are seen in the c the t s of the Con val tw o of orrie on nor h ide Little , miles west ' Dufitow n w fin e of a m m s s , here a specimen ter inal oraine cro es the ut of the c has cut t u two ac s mo h orrie , and been hro gh in pl e f by the small s tream that has its s ource on the slope o the hill . s s t c a s of the Conval a t a The e ec ions en lose l rge block gr ni e , and mas s of the same rock rests on the summ it of the m oraine at its r fu c s of sm a t a western end . There a e rther indi ation ller ermin l and a a s a an d the a l ter l moraine , both bove below large mor ine H described above . L . W . .

RECENT DEPOSITS .

W T A — a t e c of u v um are FRESH A ER LLUVIUM . The l rges str t hes all i f u a c u s of the S s and the B c Bu . o nd long the o rse pey , the Los ie , la k rn Below Pluscard en Abbey the Black Burn m eanders throu gh tw o w s of fin e a a u u t t at m s ide haugh s ndy ll vi m ha were one ti e marshe , b ut have been drained by diverting the stream for s everal miles a a t fi A c s t of a u um into deep r i cial channel . on iderable s retch ll vi is a s f u at B t ut of Da as an d d ue t o a l o o nd e helem , to the so h ll , is the c ur of s w c at m w change in o se the river Los ie , hi h one ti e flo ed u the w - c n s ut of Ballachra an b ut thro gh ell marked ha nel o h gg , now a s of t fa of Da as s tu p s es to the north hat rm . The village ll is i ated on the low delta laid down by the Loss ie at the head of the lake at the H u of D x u ia th once covered a gh allas . This e tensive all v l flat f of a an d t of it is u t at is ormed fine s nd shingle ; a por ion c l iv ed , the w . the a u as rest being covered ith peat In region ro nd Kell , the Lossie has eroded the thick glacial deposits that fill this river u a of basin , prod cing fine series terraces . These terraces he below t of fluvio- ac a h of m 62 f hose gl i l origin , the hig est the being eet

of . J G. . above the present level the stream . S . W 7 2 Exp lanation of Sheet 85

h fl od The alluvial terraces that s how the successive levels of t e o plain of the Spey are well marked along the whole cou rse of the u t s river thro gh his heet . B t Ballind all as a f u six e ween och and Carron , m ny as o r, five , and of these terraces can often be distinguished on either side of the is d iffi river . The highest of thes e sometimes merges into , and f flu io- cult to separate rom , the v glacial deposits which in places — flank the sides of the valley asbetween Blacksb oat and Knockando . The high-level terraces s een on either side of the Glen of Rothes can be traced more or less continu ou sly by Rothes and Blackhall ma into the Spey valley , and y be correlated with the 500-f t s P an d C ul u oich u eet errace at hones q , higher p the river, c a cat an a c u of S near Kno k ndo . They indi e e rlier o rse the pey t u the G of R t s f to C a . S hro gh len o he , re erred in h pter II imilar

' high-level alluvial deposits are continu ed up the valley of the A and Ballin dalloch and D m von , are well seen between ru in , where the old castle stands u pon a fragment of a higher terrace . The materials at the lowest levels are coarse and often torrential b ut c u a s as in character, be ome finer pw rd , and p s , in the highest t s fin e sa an d t . s t s in errace , into nd sil Thi poin s to a progres ive crease in the gradi ent and cons equ ent velocity of the stream as it cut down throu gh the depos it of an earlier was te-filled basin t o the rock floor over which it is now flowing in this port ion of its H u s . . . co r e . L W Between Dand aleith an d Aiken w ay Castle there is a consider a of flat a u a w of w ble stretch ll vial l nd, the lo er part hich is locally H u f R t s u i known as the a gh o o he . This all v al stretch lies imme ia the c c of the a the P of Sourd en d tely above onstri tion v lley at ass , an d forms a basin that before the lowering of this rock-barrier m ay

have been occupied by the waters of a lake of considerable s ize . N s f Beat of B of the m a the orthward rom ridge to the edge —p , Spey has laid down a broad stretch of terraced alluvium that at Fochabers meas u res as much as 2g miles in ex tent from east t o - m t f Inchb err w . A it s c the a s o est p e tion by ro d ide i ile nor h y, in the s b ut of t ac s s w n highe t one these river err e , ho s an alter ating

of and a a s fin e a s . series fine co rse gr vel , sand , and clay b nd As the majority of the streams on the east side of the Spey run u a w t a fa few x thro gh narrow v lleys i h rapid ll , there are e tensive f A allu vial deposits in this part o the area . broad belt of peat x t Mu N w covered alluvium e tends be ween lben and e mill . The greater part of this area was in all probability laid down when the k rt s burn of Au chlun a flowed ea twards into the Isla . It has since b the Mu Bu e been beheaded y lben rn , and its wat rs now flow west N f u w ards to the Spey . arrow stretches o all vium occupy t he of of Fid di ch Du Deveron bottom the valleys the , llan Water, , and

J . S . G. . Isla . — W PEAT . B a i u ma asin peat is very gener lly d strib ted all over the p , and in the area between the Lossie an d the Spey there are some - very large and deep peat mosses . The largest moss of this area is of Bednawin n D b u ua that y, near allas , which is a o t one sq re mile in t the c f u ex ten . In past these mosses were the hie so rce of su pply Glacial Dr t and Recent D 3 if ep osits . 7 for the fu u in the d ist i t are a s el sed r c , and they now in many c se x r u ht to u the ca st t e tensively w o g s pply lo l di illeries . At the Ke tles and the surrounding peat mosses large roots and stumps of Pinns S coticus are f u at the t of Dou lasshiel o nd bot om these bogs . The g and Gow M s s su l t t t of fu an d o pp ies Kei h wi h a por ion its el , in the Lower Cabrach the peat mos s between Craigwatch and the B n H row ill is very deep . to as c of u t In addition the b in peat , a large tra t co n ry lying on the watershed betw een the Spey and the Lossie is covered with hill ' of c w Dufltown and the s u peat varying thi kness , and bet een o th east com er of the sheet a similar covering envelops the hill-tops

G. . and ridges . J . S . W On the w estern s lopes of Ben Rinnes and in Glen Tervie there are a at s t of whi for fu . N sever l pe mo ses , mos ch are worked el one of these is of very great extent ; the largest are fou nd in the Drum of Ca the a t of Carnaca an d at a of rron , on e s ern slope y, the he d

Tervie a fa m of Tomachclaven . A at Glen , ne r the r larg e pe moss appears along the w estern m argin of the map at the foot of the Lari H a a s d u at a u the a g ill , and pe t is l o g v rio s points along v lley ll B Auchn llin of the A t reac below aga . The probable exhau stion at no very distant date of the more s s of as at - at t at c u c acce ible areas b in pe , renders the hill pe , h overs s h w a s of s m m a s fu ide rea in this region , ome econo ic i port nce , thi el being s o largely u s ed in the nu merou s distilleries of Banflshire an d H Elgin . L . W . . 74 Exp lanation of Sheet 85.

CHAPTER X .

E CONOMIC PROD UC TS .

The principal rocks of economic valu e in the district are the ‘ st s of the Ban flshire s t c - lime one eries . The wo prin ipal lime works s of the c u t are s uat at Blackhillock a in thi portion o n y it ed , ne r '

t an d P m an d Tininver Dufitown . a Kei h , at ark ore , There are sever l small openings in Morinsh and along the outcrop of the limestone G R a s G Fid dich Glenmarkie Corsemaul in len innes , l o in len , , , w w u la r H n d l h A Do sb ae and a s ac . t a Lo er To ie , g , Keith , oper tions ar Blackhillock m C a an d are c ried on by the Li e omp ny , Limited, the annu al ou tpu t of lime is from six thou sand to seven thou sand tons per annum . The limestone rock in the quarry is of a very

h u a and a m a a J . F hig q lity , sa ple has been n lysed by alconer King , C A a st E u w t f w su t ity n ly , dinb rgh , i h the ollo ing re l s Carbonate of lime Carbonate of magnesia Sulphuric acid Iron ox ide and alumina Water Sil ica

1 004 3

The lime manufactured by this company is t o a large ex tent us ed for u il a -f ur f b ding and pl stering work , while less than one o th o the total annual ou tput is u tilis ed by the district farmers for agricultural

u . a to a u m s c p rposes In ddition the loc l req ire ents , thi ompany u s i s ct t n s s pplie lime to the w de di tri between Kei h , Inver e s , and A s u berdeen , and it al o consigns by rail to Wick , Th rso , Kyle of B Lochals h and allater. Pa m and Tinin ver - t The rk ore lime works are the proper y of Mr. for Kemp , Keith , and have been carried on by him many years . The Parkm ore works are situ ated on the east side of the railway ' uct w s s Fiddich of Dufl viad hich cros e the river to the north town , an d the kilns and lime stores are connected with the Great North u ta s in of Scotland Railway by s i ble idings . The T inver quarry is ' c the Fidd ich Dufltown . lose to river , below In both these quarries ua t of x the q li y the rock is e cellent , and they are both working the same zone of limestone . Their joint annu al outpu t of marketable f a a u lime varies rom nine to ten thous nd tons per nn m . Its qualit ” y a as st c is known in the tr de a fir class S otch lim e . The lime produced at these works is chiefly us ed by builders and s in for plasterer , and a lesser degree agricultural and gas pu rifying Economic Prod ucts. 75

' u It the G at p rposes. is consign ed to all districts served by the re North of Scotland and Highland Railways between Aberdeen and Ca ithness . At these joint w orks eight kilns of the Clamp type are st m the Pa ua w as s con antly e ployed. When rkmore q rry fir t

out c t u u u ct . opened , on in o s b rning kilns were ere ed These were s imilar to those at pres ent in u se all over the Carboniferous Lim e ’ s t Aft a f w t a one dis tricts of the North of England . er e years ri l t s s a a n the t s he e kiln were b ndoned a d presen type adopted . Thi c a w as c s a a t acc u t of the u h nge rendered ne e s ry , p r ly on o n req ire ments of the North of Scotland lime trade and also the difficu lty of getting the proper clas s of fuel neces s ary for their most economical

A of f Tininver u D ufft nalysis limestone rom Q arry, own , by

J . Fa C A E n " lconer King, ity nalyst, di burgh *’ Lime Magnesia Iron ox ide C arbonic acid Sulphuric anhydride Organic matter Water Insoluble matter

1 000 6

i u f u for This limestone w ll, when b rned, orm a lime well s ited u a u - u f n b ilding, gricult ral , or gas p ri yi g purposes .

g S J . FALCONER ING. ia, ned K

A of f B J . F nalysis limestone rom raehead Quarry, Keith , by alconer King

Carbonate of lime magnesia i ron

u . Lime as s lphate, silicate , etc Sulphuric acid Organic matter and loss Moisture Silica and insoluble matter

1 000 0

Communicated b Mr ames em eith with ermission to u ish " y . J K p , K , p p bl ]

U Old Red S ff a f The pper andstone a ords good reestone, which n u D a P u r n has lo g been q arried at all s and l sca d e . A ro ugher stone of f a a F a local use is obtained rom the lower str ta ne r och b ers . The slaty phyllites have been wrought for roofing- slate at New i M Tarr mount u at m ll, ulben , and y , but the large q arry the last

E ua to car onate of ime 97 2 0 er cent. q l b l , p 76 Exp lanation of Sheet 85.

s a s named locality is now abandoned . The black schist h ve al o been ex tensively quarried on the western slope of the Scalp Hill near Auchind oun Castle and to the north - east of the Hill of u e for M ackalea. Granite and gneiss are q arri d local building purposes at Ruthrie and on the Blue Hill near Aberlour ; b u t dressed stone for lin tels and ashlar work is imported from the l n E gi district. — d BRIC CLA . f of s s an K Y A considerable manu acture brick , tile , a n- C a — a is dr i pipes is carried on at raigell chie, where terra cotta w re also made from the finer parts of the glacial clay .

S. G. J . W

d i . Roa s , H g h w ay s , an d Road M et al

With the ex ception of the three small areas of Elgins hire and the narrow strip of Aberdeenshire along the eastern edge of the of r S map , all the roads and highways on the east side the iver pey in this sheet are included within the second or Keith d istrict of the

of ad l I. . . county These ro s are c assed as , II , III They a n n h ve , along with their bridges , bee much improved withi the ten are past or twelve years, and now throughout the whole district a t in a very fair and passable condition . Three years ago s eam C u C roller and plant were purchased by the o nty ouncil, and in the parishes where there is traction engine and other heavy traffic the former unsatisfactory condition of these roads has been immensely u ff improved by roll ing. The road metal sed in the di erent districts d ue of is very diversified in character. This is partly to the cost for f carriage any considerable distance rom the good quarries, and also to the initial e xpense which would be incurred in providing means of access to places where suitable rock is situated at some f distance rom a public highway .

Und er the Local Government (Scotland ) Act 1 889.

hee 8 78 Exp lanation of S t 5.

TAB LAR S TATEMENT OF ROAD METAL SED IN THE CO NTY OF U — U U ELGIN SHEET 8 5.

From information su ied b Mr. ALEXANDER HOGG C .E. C ount Road Sur e or. ppl y , , y v y

Paris h . Loca it C ass of Meta . Remar s. l y. l l k

FromFochab ers war s tream s to nes . Fair ood ua it to d S g q l y. Ta en from Focha er Keith . k b s

Burn .

Focha ers Stream and fie d s tones . From Ri er S e and b . l v p y heaps carted oif land . Fair good quality.

T n Stream stones . From Focha ers Burn y et . b and other s treams Fair oo g d quality.

S e mouth Di e . DO . an fie d s tones From Ri er S e and p y , ppl d l . v p y e h aps carted off land . Fair ood u g q ality.

Rothes Orton. Do . Ri er S e . Fair ood ua it . , , v p y g q l y

Rothes Police Borough Blue greyquartz -s chists Bottom of quarry good Crofts u rr ua it i s f Q a y; q l y ve n o Barytes .

Stream s tones R. S e . Fair ood ua it , p y g q l y. - Water worn s tones and Pits N .E . of Birchfield stron it r ood roc c u d b e g p g avel . g k o l g ot to wes t . l sc rd en Stream and i s Of fair u P u a . p t tones . q ality ; from glacil d eposits ; good roc to west f k o Abbey. h w n Hard tz o fels Ver su erior ro Kinloss Sout La re ceton Quarry. Quar y p ck for pathic g neiss with road metal the best s ma ranite eins in the count ll g v . y.

Forres Wester New Forres .

Rafford Briach to Raff ord from Lawrenceton and

Wes er New Forres Do . d o. d o Do . d t . . o . Other arts of Parish Water-worn and and Good ua it p . l q l y. stones

h Wh e Pari h DO . T e ol s .

Birnie The who e Parish. Do . Good , l rock available to the E . of Shougle .

noc and o Eas ter E chies uarr . Decom osin ranite . Good ua it . K k , l Q y p g g q l y Water-worn and an D Do d o . . l

s tones .

- uarr near Carron Granite c ose rained . Rather s oft Q y , l g .

Road Station. - rron Water worn and and Good ua it . Ca . l q l y s tones

The whole Parish. Wells 9 Mineral . 7

M ineral W ells

Chalybeate springs are of frequ ent occurrence along the outcrop - A n f of the ferru gin ous black schists . mongst the bes t k own o ’ are P a Dufitown u these the riest s Well ne r ; a well at T lloch, west of Kininvie and a very strong iron spring which rises in the of a a of B H th w C middle pe t moss west rown ill in e Lo er abrach , f r and has a great local reputation o its medicinal qualities . The water of the bu rn below Tulloch is also strongly impregnated with alum derived from the decomposition of the iron pyrites in the black schist .

Iron .

A thin vein of ironstone w as at one time wrou ght on the western

of Ben A Arnd ill . J . S G. base igan , near y . W .

dix 8 1 App en .

APPENDIX .

I PART .

PALE ONTOLOGICAL .

NOTE ON THE FOSSIL FISHES O F THE OLD RED SANDSTONE

O F SCO LAND BY DR . RA A R F .R.S . T T QU I ,

M r H ha i as d me t o fu ish a i f stat m t a d i . orne v ng ke rn br e e en reg r ng ou r know ledge of the d istribution of fossil fishes in the Scottish Old Red Sand st I sub mit the f w in t s which i in fact the one, ollo g no e , g ve , , s ubst ance of a paper read b y m e at the meeting of the British Asso

iation at G as ow in S t m 1 901 . c l g ep e ber , There are three d istinct fish -faunas in the rocks d esignated Old ” i i The fi st is that of the w Red Sand stone n S cott sh geology . r Lo er ld Red Sa d sto of the c nt a a of Sc t a d t ica d d O n ne e r l v lley o l n , yp lly evelope in Forfarshire its characteristic fis hes being Species of C ep halasp is and Pteras is as w as Acanthod ians of the a Olimatins Parexns p , ell gener , , - Enthacantkus I sol maca/nthus and M esacantkns . his fish fauna is , , T closely allied t o that of the Low er Old Red San d stone of the West of E n la d which is a ai i d with thos of the ow D nia of g n , g n l nke e L er evo n

S itz b O f Pod ia and of C am b l t w in C a ad a. It d iff s p ergen , ol , p e l o n n er , h w f m that of the ow D ia C if us im st n of o ever, ro L er evon n ( orn ero L e o e) the it d Stat s ma d in the a s c f m the att of the Un e e rke ly, b en e ro l er t i tic Pter i ians and C e halas id ians d s the Cor charac er s asp d p p , nor oe M koer u b It niferous Show any Acanthod ians unless ac acan th s e one . m us t be m mb d how that the C if us im st on is O f re e ere , ever, orn ero L e e ur ma in o i in h in f m d u d co d iti s p ely r e r g , av g been or e n er n on very d ifferent from those und er which the Lower Old Red of Forfarshire or it d the Low er Devonian of Canad a were d epos e . — The second great Scottish Old Red fish fauna is that of the O cad ia s i s which i s t o the th of the G am ia s and this r n er e , l e nor r p n , fauna is st i i d iff f the F fa hi n r k ngly erent from that o or rs re bed s . O ly two a and n ot mm n t h The gener a single species are co o o bot . occurrence near Thurs o of species belonging t o the Forfarshire Acan - thodian P ct/reams recurva c A as s has b m ti d b Sir A . G iki , g , een en one y e e

the auth it of the at M r C . P ach b ut th must a on or y l e . W . e , ere be mista of id tificati n h for I ha all the s cim ns of ke en o ere, ve gone over pe e Caith s s fish- mai s c ct d b M r P ach which are in the B itish ne re n , olle e y . e , r Mus um in the Mus um of P actica G and in the Ed in u h e , e r l eology, b rg M us um of Sci n c and Art with ut findi a trac of P arexus e e e , o ng e , nor ha I s it in an oth c l cti n of f f m th dia d ve een y er ol e o ossils ro e Orca n be s . Parexus recurvas d s h w ccu in the ow ld Red Sand st oe , o ever, o r L er O one Of Hereford shire . Not are the F fa sh and O cad ia fish-fau as disti ct b ut only or r ire r n n n , h i s cti faci s s m t o i t in t d i cti ns The t e r re pe ve e ee po n d ifferen re o . 82 Explanation of S heet 8 5

i tic Si u ia Pteras pid ae and C ephalaspid ae are al so character s Upper l r n th th ha d fami i s as in the st of E a d and s wh . On e , l e , We ngl n el e ere o er n l s the O cad ia fish -fau a h t is d b Ast id ae P terwht g/ , r n n , c arac er e y erolep , ( f d M icrobm ckins Aca th did ae keim canthns Di laccmthus Ost i ), n o (O , p ), eolep ae Os teole is Di lo t r hiz od ontid ae G ro t chiu s Trzstz ( p , p p e as , Thu rsius R ( y p y , ), . cko teru s H t chi idae l tol e is Ct d tid a teru s p ), olop y (G yp p ), eno on e (s ) 1 8 as C cc st id ae Coccosteu s Homos eus Pa ae scid ae Cheirole is , , o o e ( , t ) l oni ( p ) a r ad ma d b M r a s m a i d t o that of the l e y re rke y . J . W. Ev n , ore ll e Upper Old Red t o which it is i e ma sa the set of fish s f u d , l nked , w y y, by e o n a a Of the two in the Upper Devonian of S caum enac Bay in C an d . a which ar m a and F fa shi d s n am gener e co mon t o the Orcadi n or r re be , ely Ce halas is and M esaca/nthus b th also ccu in th s C a ad ia p p , o o r e e n n Upper ' D nia st ata b ut it must b n t d that Ce hala s s o cha act istic evo n r , e o e p s , r er a w D n ia nus is n w f om the O cad ia and Scaumenac Lo er evo n ge , k o n r r n

Ba st ata b a sin u ni u s cim in ach cas am 0. ma y r only y gle q e pe en e e , n ely, g ' d n ca fi a and 0. latice s Tra . s cti . It ma als add w , q , p , q , re pe vely y o be e that Coccosteu s th u h n ot ccurrin in F fa shi is i Ce halas is , o g o g or r re, , l ke p p , a us which s thr u h the tir f mati i f un d not gen goe o g en e or on, be ng o only in the O cad ia s i s b ut als in the w D ia of G man r n er e , o Lo er evon n er y (Hunsriickschiefer) and the Unit ed States (C orniferous ) as well as in the D nia of Ca ad a and the Old Red of Sc tland . Upper evo n n , Upper o N or d oes the Orcadi an fis h-faun a present any greater affinity t o any of the Low er Devonian fish -faunae of Europe or Am erica than it d oes t o th s of F fa shi H f d shi . S cant h w as is the fish o e or r re or ere or re y, o ever, mat ia c ct ed f m the M id d D nia of the Eif it is i t er l olle ro le evo n el , n er esting t o note the occurrence there of a well marked species of

erickth s Pt . Rhenanus Be rich and of a s ci s fe d t o Pt y ( , y ), pe e re rre le is b P f ss von K th i mi t O cadia Osteo p y ro e or oenen, bo be ng pro nen r n a gencr . The thi d at fish fau a is that of the Old Red Sa d st r gre n Upper n one, cha act is d Psammosteu s Asterole is Bothriole is Pk llole is r er e by , p , p , y p , l to omu s S aw i terus Holo t chius and PhanerO le'u/ron which G yp p , p , p y , p , pl ace this series of rocks on the s ame general horiz on as the Upper D ni a of the N o th-w st of Rus sia the Famennien of B ium an d evo n r e , elg , the Cats i of the it d States —the fish- mai s of the Sh t a d d s k ll Un e re n e l n be , w i ti t o a siti c es din t o that of the C h mu ho ever, po n ng po on orr pon g e ng ia h t t B thr l an group (Upper Devon n) of t e Western C on inen . o io ep is d lo t chius are the m st mi nt a of the U Old Red and Ho p y o pro ne gener pper , t is i t stin t o s that th u h the fish-fau na of the i n ere g ob erve , o g Upper D evonian of S caumenac Bay has m any points of afiinity with that of the O cadia s i s the O As terole id s t is a Botkriole is B r n er e , nly p pre en p ( .

d nsis Whiteaves . Cana e , ) ‘ The statemen t by the late Sir Frederick M Coy (Report on Palaeon

t olo in Ann . Re . of S c ta for Mi s Vict ia 1 8 8 9 as t o th gy p e re ry ne , or , ) e ccur nc at M a sfi d in Aust a ia of a Pteras is and of h o re e n el , r l , p , fis es s cia a i d t o Ce halas is Di lacan tkns and keirole is in pe lly ll e p p , p , C p the same bed s with Palaeoniscid m of C arboniferous type is clearly found ed on t mi ati ns The wh erroneous de er n o . ole collection on which this Report as d has us t b f wa d d t o Dr Smith w as b e j een or r e . Wood ward for d es crip ti an d I ha his missi t o stat that ha i t th ca f on, ve per on e , v ng oge er re ully d all the s cim s we f u d t ac f an Pt looke over pe en , o n no r e o y eraspidian or C e halas idian i d d of an thin s cha act is i p p , or, n ee , y g el e r er t cally Devonian . f th fi h -f u The facies o e s a na represented in this collection is u nmis ’ er u takab ly Cwrbonif o s .

H RA AI . R. . T QU R 83 Ap pendix .

S or THE F L RR NG AT TYNET B RN IN THE ORC AD AN LI T OSSI FISHES OCC U I U , I

SER ES BY DR. R . H . RA A R F .R .S . I , T QU I ,

’ P terzchth s M illeri A ass Di lo teras A as siz ii Trai ] . y , g p p g , l ' ' p rod uctus Gyrop tychzus microlep zd otus (Agass .

Gl tole is le to terus A aes . oblongus _ yp p p p , g ' ' Chezra a t r hisoni A ass . Di tcrus Valenciennesn Sed w . and c n hus M n c , g p , g

lat E ert . M urch. us , g '

D i lacanthus striatus A as s . Coccosteus d eci zens A as s . p , g p , g

Osteole is a r e i otus A ass . Cheirole is Trailli A ass . p m c ol p d , g p , g

S ci s ccur in at Gam i and e s wh the M a Fi th pe e o r g r e, l e ere on or y r , b ut which I have not seen from Tynet Burn as yet

’ D aca thus l is inus A ass . pz l n n p , g ri tenuist atus , Traq .

NOTE ON THE FOSSIL PLANTS O F THE OLD RED SANDSTONE

R I F . S . O F S COTLAND BY M . R. K DSTON, . R

The Foss il Plants of the Old Red Sand stone of Scotland Show a d fi d th —f d d i isi of this f mati The a is not clearly e ne ree ol v on or on . flor n um us in t u s ci s for ma of the s ci s w hich ha b ero r e pe e , ny pe e ve een made have b een found ed on material far too imperfect to be of any scientific value . ' ' R c d s of the ccu r c of Le id od end ron Calamz tes etc. in t he e or o r en e p , , ,

Old Red Sand st of Sc t and m us t I am af aid b e ca c ed . In one o l , , r , n ell s m cas s I ha s e the s cim s which the c d w as mad o e e ve e n pe en on re or e, and with the m st i a i t tati of th s a it is even o l ber l n erpre on e e gener , impossible to ad mit the Specimens into the genera in which they had been placed . The upper d ivision is characteriz ed by the occur ren ce of Ao'chceop ' ' ' kibern icw F s s . and c tai s an a t th d isti ct a f m te ms , orbe p , on n l oge er n flor ro in d i i i n that of the two und erly g v s o s . The O cad ia d i isi c tai s a e c mm a t Which I r n v on on n v ry o on pl n , '

d d as Psilo h ton robus tzu s Daw s . B tt e and m rf ct recor e p y/ , on e r ore pe e s cim s ha sh w me that I w as in and that the a t I had pe en ve o n error , pl n i d t o Psilo h ton robustius Daw s w as the w t i of bel eve be p y , on, lo er por on the a t wh s u a t was t he Ptilo /z ton Thomson/i Daw s pl n , o e pper p r p y/ , on , ’ a his S i i whose stem is the C au lop tems P eachii of S lter . T pec es s very “ mm in the C aith ss a s and is ti abs t f m the P th co on ne fl g , en rely en ro er ' - shi and F fa Old Red st ata. The so ca d L co od ites M illem re or r r lle y p ,

Sa t and a few th s ci s are a s culia to the C aith ss a s . l er, o er pe e l o pe r ne fl g The Lower or Perth -Forfar Old Red is characteriz ed by the presence

r in ce s Daws o and var . ornatu m Daws P silo h ton of Psilop hyton p p , n , , on, p y ’ us Daw s Arthrostz ma o'acilis Daws Z oster' o k llnm robus ti , on, g g , on, p y

r ianum Penhallow and Parka, d eci iens F mi etc . My ton , , p , le ng,

" far as I w at s t ach of th s d i isi s is cha act iz d AS kno pre en , e e e v on r er e fl cul ia to its f b ut the wh su ct ui s a th u h by a ora pe r el , ole bje req re oro g he i ht of m c t dis c i s revision in t l g ore re en over e .

R . KIDSTON . EEp lanalion of Sheet 85.

PART II .

LIST O F PUBLICATIONS REFERRING To THE GEOLOGY AND MINERALOGY OF THE D I SHEE 85 ISTRICT INCLUDED N T .

1 7 75. Hist of the P haw ory rovince of Moray . S .

“ 1 8 3 An ac h P c 0. count of the Great Flood s of A ugust 1 8 29 in t e rovin e

of M a and the ad ini dist icts b Sir h s . Dic or y jo ng r , y T o k ud Bt La er, .

“ 1 8 35. Essa the G of M a b J h M a ti Hi hl and y on eology or y, y o n r n . g

S oc. Tm ns . Vol . V . new i s . , , ser e

“ 1 8 36 On the G of M a sam auth . u art. J ourn . . eology or y, e or Q A ricultw e N O V g , . XXX

1 8 40. G ica Ma of Sc t a d J h M accu ch F R S eolog l p o l n . o n llo , . . .

“ ' 1 842 S tch of the G of M a b Pat ic Dufl . ke eology or y, y r k .

“ ' 1 842. The G s of Banfishi rc b R F H Cunni ham . Trams . eogno y , y . . . ng Hi hl an d oc Vol X IV g S ., . .

“ 1 842 h R ati s of the d iff a ts of the ld Red Sa d . On t e el on erent p r O n stone in which Organic Remains have recently been D iscovered " ” in the C unti s of M u a Nairn Banfl and I ss b J . o e rr y, , nverne , y

G. M a c ms M .D . P roc. Geol . Soc. V ol . III . l o on, ,

“ n the Sa d of M a shir and E i c tai i Re 1 8 58 . O n stones or y e lg n on n ng p ti ia R mains and th i R at i s t o the Old Red S a d l n e , on e r el on n ” st of that C u t b Sir R . I . M urchis . u a/rt . J ourn . one o n y, y on Q

l c Vol . X V . . 41 9 Geo . So ., , p .

“ 1 8 59 The Ge f the w N th a t of the P i c of . ology o Lo er or or ern p r rov n e ” M a b Dr G d of Bi ni Edin . New Phil. J owrn or y, y . or on r e .

Vol . IV.

“ N t s F ssi if us ca iti s of the Old R d Sa d to f 1 8 60. o e on o l ero Lo l e e n s ne o

the East of Sc t a d G . The Geolo ist Vol . o l n , regory g , pp . - 1 42 1 48 .

6 Ge of the N th of Sc tla d b P f Ni l 18 6 . ology or o n , y ro . co .

' 1 87 1 . On the O d M tam hic R c s and G a it of Banfishire l er e orp o k r n e ,

b . F . Jami s F .G.S . u art. Jow n Geol S c Vol y T e on, Q . . o ., . XVI 101 X I ., p . .

1 8 Sam tit and auth . Geol . Ma . Vol VIII 1 34. 77 . e le or g , . ., p .

86 “ Eap lanation of Sheet 85.

I PART II .

LrsT OF MIC ROSC O PIC SECTIONS PREPARED FRO M RO CKS C O LLEC TED

Locality.

Biotite Granite . G ac Harness etween Round See . l k , b p Hi -‘ l l ll and Meik e Conva . a r t e See . 8 7 . C rron, S t a hsp y . p

Ruthrie A er o ur. See . 36 . , b l p

B rn of othes e ow et h l . See . 38 . u R , b l N er y p

’ ‘ S W N ether 2 miles S.

ee Quartz Diorite. 4 mile S. of Dand aleith. S pp.

ee 3 38 . S pp . 7,

38 . See pp .37 ,

' Hil l a o e C on e oc Rothes . See. . 33 . b v R k, p

E. of Sto Hi l . See .33 39 . b l pp ,

r - Netherl Bu n of Rothes See . 38 41 . y, . pp

- See pp a38 41 .

- Bi otite Granite. cuttin E. of tun e See . 39 . g , n l p ll achie.

Di rite with i c sions e Ab erro r. ee . 37 . o , n lu , u S p

s chist .

’ ’ ' Cam t onite . E . an of S o ush Poo See . 41 . p b k pey, H llyb l , p i 8 7 App end x.

‘ L a it oc l y.

Au en Gneiss . eith Banfishire. See . 44. g K , p

Horn b end e Schis t. Kin shau h B ac water. See . 46. l g g , l k p

' B ac water 2 mi es a o e Ar d we See 45. l k , l b v ll p .

i Ep diorit e . See p . 44.

F as er Ga ro. B ac water 1 mi e N of Lod e. l bb l k , l . g

" ale Horn end e chist 300 ard s a ove rid e o er B a See . 46. C bl S . y b b g v l ck p water Ard we l , l . ' Horn end e Schis t. Bum at Find Ouran Burn Tre l e . Se 29 . bl , b e p .

Horn end e Roc . Shenwell B ac wat er See . 4 . bl k , l k . p 5

"

Dia a e Perid otite. Crai d orne Ri er Deveron See . 45. ll g g y , v p

a i Loc l ty.

Biotite Gneiss. Crai e achie cuttin See g ll g. p .

See p . 32.

’ Musco ite Bioti te GIIEiSS . Bl ue Hil A er our. ee 32. v l, b l S p .

Biotite Gneis s and Bio ite S ac of Ballanteem er our. t l k , Ab l

Granite .

Garnet Mus rite Gneiésf. Rothes Burn cm . See p . 28 .

uartz it . Hunt Hi l . ee 31 . Q e l S p .

- z F ls r Hornfe s . uart e a Netherl Bu rn of Rothes . ee . 51 . Q p l y, S p

Biotite Hornf e s . l See p . 51 .

See p . 51 .

ierite Hornfe s Cord l .

And a usite Hornfe s . e l l S e p . 53.

' '

uartz ite . North end of Cr i e achi Brid e ee 51 . Q ag ll e g . S p .

Biot te Gra ite an Biotite Ba l nteem A er our i n d aa , b l . See p . 5] Schis t. 8 8 Exp lanation of S heet 85 .

' Banfishire S eries .

Name.

ee . 23. 9556. Grit . t Deach Ard we . S Al l , ll p

See . 48. 1 59 . Micaceous Grit ummuir S . of eith . 7 . Dr , K p

ee . 48 . 981 . Schis tos e G it i w cuttin Mu en. S r . Ra l ay g , lb p

Ph ite See .21 48 . 933. yll . pp ,

e 21 48 . Se pp . ,

See pp .21 ,48 .

S ee pp .21 , 48.

See 21 48 . pp . ,

1 61 uartz ite with a ate eins Cone Hi Rothes . See . 1 3. 7 . Q , g v . ll, p

’ 2 2 4. Mica S chist. Hau h s uarr eith . S ee . 2. 07 g Q y, K p

1 6 Limes tone. Blackhillock uarr eith. See . 7 5. Q y, K pp

See . 1768. Micaceous Limestone. pp

4 S ee pp.18, 8 .

See pp .1 8,48 .

1 B ac Schist with remo ite. Boharm . See .19 50. 209 . l k T l pp ,

d o Actino ite Belna arrow a mi es N .E of Crai See .l 9 50. 9594. . l . g , t l g pp ,

’ 0 959 . B ac Schist . 1 m l ‘li cf d in ton Ho. 2 See . 2 . 7 l k g , } p tgplegé éf keg See 19 Stream between Blackhillock and p. . ’

Tu och 2 mi es N . of Dufitow ll , l

9 64 Cale silicate Hornfe s . Near Tullochallum p ufitown . See .50 56. 5 . l , pp ,

Rai wa cuttin E. of Dufftown. See .50 56. l y g pp ,

~ 9 0 Chias to ite S ate. Ar d we Inn B ac water. See .53 54. 6 30 l l ll , l k pp

60 Biotite Hornfe s . A o e B ac water Brid e Ard we . See . 56. 9 3. l b v l k g , ll p

’

9599 And a us ite and Stauro ite B ac wate r 2 mi es a o e Ard we See . 54. l l l k , l b v ll p and Brid g e . 9599b e mi es N See 0 Cal careous Grit. Litt Newt on 2 E . of . 6 . 9595. l , l p C rai e achi g ll e.

9 0

E conomic frees tone, 75. ir n o , 79 .

imestone 74 . HA TON ARR fossi s from l , T QU Y , l , minera w e s 79 . Herric s M oss 1 4 8 . l ll , k , , 6 road meta 76 77 . Hi of Sto 31 33. l , , ll b , l l , , s at e 75. l , d iorit e of, 33, 39 . Ei d on H i 1 27 . Ho ush Poo l ll , , llyb l,

E id iorit e 29 . p , Horn end e s chist 29 44 46. bl , , , etro ra hica chara ct er of s on 39 4 . p g p l p g y, , 0 contac t a tera i t on b 47 . HORN E Dr 58 64. l y, , . J , Erra i - t c locks 66. Hornf l in 1 b , e s g , 5 56.

I SLA RIVER 2 4 6 61 72 . FA L S , , , , , , U T , 3, 60.

Features d ue t o fau tin 3 . l g,

acia action 3 . gl l , Fid d ich Ri er 2 5 1 4 15 1 , v , , , , , 7 ,

Fossi ist s l l KE H 1 1 IT , 0, 8 , 22, 31 , 44. from Bur i e House . g , 64 KEMP 4. , J 7 from Hatton uarr 4 . Q y, 6 ID STON R. K , , 58 , 83. fro Plu m scard en , 64. K NG . FALCONE R 4 5. I , J , 7 , 7 from S caat Crai . g , 64 noc and o 24 2 0. K k , , 7 , 7 from rr To ies t on , 64. from T net Burn y , 83 .

Fo iated ranit e 31 44 . l g , ,

LA GH or M ORA 1 7 . I Y , , La es k , 2. La ant oul We s 1 6 . g ll , Lam ro h re p p y , 35, 41 . GABBB O 30. , Limes tone 1 —1 , 6 8 , 20, 74 . etro ra h of 44 . p g p y , etro ra h of 4 . p g p y , 7 C ar et Hi b ll , ana ses of 74 5. - ly , , 7 E ir . GEIKI , S A , 8 1 . uarries 1 . q , 8 C co o ica features 3. l l , Loch Da as 2 69 . i h l ll , , Gheal s d , Al t , 2, 26. Loch Noir, 2. G en Fid d ich 1 4 1 5 1 8 23. l , , , , L ch P ‘ o ark, 1 7 . G en Li et 25. l v , Loss ie Ri er 2 27 28 1 , v , , , , 7 , G en M ar ie 1 5 1 8 21 29 . l k , , ,

G en Rinn es 1 6 22 68 . l , , ,

G en of Rothes 3 6 28 60 72. l , , , , , - G acia d rift 65 7 1 . l l ,

s triae, 65.

a es 0. l k , 7 MAC E Dr. 28 42 51 — KI , , , , , 57 , 66. Granit e, 3 , 1 0, 31 33, 37 . — Mica-schis ts of Ben Rinnes 1 0 31 36 . , , ' — of Banfishire series 21 23. of Hunt Hi 31 . , ll , of ent Hi h — C ra and Series 25 28 . of Ruthrie 36 . l g l , , Minera we s , 79 . ana ses of 43. l ll ly , — — Moin e s chists 10 24 27 46 . et ro ra h of 36 38 . , , , p g p y , Mora 1 y, . d ifferentiation of, 33 . Moraines 71 . contact metamorphism prod uced , M u en, 1 9, 20, 21 72. b 34 51 . lb , y, , Burn f o , 13. fo iat ed 31 44 . l , , Muld erie Hi of 31 . horn end ic 3 . , , bl , 7 ll Muscovite ranite 3 . Granu itic schists of C entra Hi h and s g , 7 —l l g l , 24 28 .

ro ra h of 46 4 . pet g p y , , 7

schist 19 20 48 . Graphitic , , , Gravels — fiuvi o acia 68 70. NE HER C L N 37 . gl l , T U Y, a u ia 72. Netherl ll v l , y, — 2 4 48 . d iorit e of 1 Grit s , 1 6, 3, 7, , 33, 38 4 .

N W . 46. ana ses of 44 . GU N, , ly , In dex . 9 1

Scaut Hi 15. ll ,

Ser entine 30 34 . — p , , RED E 1 etro ra h of 44 45. SANDSTON , 0, 58 64. p g p y , .

ar s occu 10. Schists ea pied by, - c as s ification of 58 . ac or ra hitic 19 21 48 . , bl k g p , , l — i mica 21 23 . d enud at on of, 4, 5 . ,

out iers of 61 . Moine or C entra Hi h and l , — , l g l , soi d eri ed from 7 . 24 27 46. l v , , — ntem oraneous a a S ates 21 23 75. co p l v l , ,

Soi s . l , 7 Orcadian series 58 . Spey, Ri er — , v U er 62 64. d aina e s s tem of . pp , r g y , l

fos s i s from 64. d e os its o f 7 2. l , p , rock sections of 27 . — , Va e of 4 6. ll y ,

Sto Hi 31 33 39 . b ll , , ,

Striated surfaces , 65.

Structure of area 10. —, Surface re ief 3 6. l , PE . ACH, C . W . , 8 1 eni e 8 . Sy t , 3 a Pe t , 7 , 72. ’ l e matite eins 28 32 42 . g v , , ,

Perid otite 45. , — Ph lites 21 23 . yl ,

etro ra b of 4 4 . p g y , 7 , 8 P ication of oine s his t s l c , TAYLOR , J 64. Pluscard en A e 63 64 1 . bb y, , , 7 TEALL . H . — , J . J , Po u ation di stri ution of 6 8 . p l , b , — T erraces , 68 72. - Pot ho es 1 . l , 7 Tervie Burn 4 20 62. — , , , Pre acia a e s 4 66 68 . gl l v ll y , , , Tininver uarr Q y, 17 . o T rmore Burn , s ections on, 25.

TRAQUAIR , Dr. , 58 , 64, 8 1 , 83.

Tre e Burn 15 1 6. bl , ,

Tu chan Burn sections on 26. l , ,

Q UARRIES n i 2 g e ss , 3 , 76.

ranite 76. g , — imestone 16 18 . l , — s an 2 5. UPPER LD RED d stone, 6 , 7 O SANDSTONE , 62 64.

schist 6. fossi s of 64. , 7 l ,

s at e 75. l , u r z i e Q a t t , 3. - of the Banffs hire series , 12 16. evid e of un conformit f 2 nce y o , 1 .

con omerat e of 1 6 . gl , of the Cent ra Hi h and series VAL LE S l g l , Y — a e of 4 6. g ,

- - - uartz diorit e 3 39 . re acia 4 66 68 . Q , 7 p gl l , , ,

Va e of the A on 4. ll y v ,

Loss ie 5. , — Spey 4 6. Veins

ca cit e 1 6 17 . l , ,

ranit e 28 32 34 42 43 . AFEORD 1 1 2 5 g , , , , , R , , 5, 0, 7 , 6 , 68 . e matit e 2 42. p g , 7, Resid ua minera s 24. l l , rtz 1 . qua , 3 Ri er s s tems 1 . v y , Road s and hi hwa s 7 g —y , Road meta s 6 8 . l , 7 7

Rothes , 6, 10, 13, 72.

Burn of, 33, 38 , 42 .

G en of 3 6 28 60 72. l , , , , , W ANGIE Hi of the 4 62. , ll , l , , W s e terton, 63, 69 .

AAT CRA G 63. SC I , - ist of fossi s from 64. Zoisite ranu ite 46. l l , g l ,