S KETC H

OF T H E

‘ Geo o of A ab gy ama.

B EUGENE ALLE N m y 51 m , Eh . D ,,

State Geolo is g t .

The five great divis ions ,based u pon the peculiarities of the f c organic life o each,into whi h ,according to Professor Gekiei, r s fi the geological ecord has been clas i ed are " (1 ) the Archaean ,

sometimes cal led the Azoic (lifeless) . or E ozoic (dawn of life) (2 ) the Pal eozoic (ancient life) or Primary (3) the Mesozoic (middle life) or S econdary ; (4) the Cenozoic (recent life) or _ Tertiary,and (5) the Post - Ter tiary or Quaternary The following table shows the order of successi on of th e m o of m stratified for ati ns Alaba a,together with the position in the geological column of those formations either Wantin g or not yet recognized as occurring in the ,S tate 2 a t c y F L G o o O A ABAM A .

T ABLE O F GE O LO GIC A L - FO A T IO RM NS .

R c - e ent S o ils an d alluvia m.

li- i l oxi or coas t formatio ns . ‘ Pleis tocene . . River terraces (s ec ond bottoms ) . ‘ Ozark sands .

5 L afayette s ands an d pebble beds .

m o s . Mioc ene . Pascagpn l a an d Grand Gulf for ati n

'g Xigfiggg white li mes tone .

Claiborne . Buhrs tone .

H atch eti b ee . ’ l Bas hi or oo d s b u fi . T us c ah oma. Nanafalia. Naheola. ‘ S u c ar noc h ee. Clayton or Ru tl

Ripley Ro l m tten i es tone . Cretac eous

l T uskal oos a.

. . Wa nting in A l abama.

Wa t i n n ing A l abama.

Pe an Wa t A l rmi n ing in abama.

oal M a es C e s ur .

1S u b - Carboniferous

D evo a B ac k h ni n l s ale .

-t n Clm o or Red mountain , ' E r en ton o r P l e a es o e . _ lh m im t n k ox d olo e an d en n mit er l;~

oc c o ' o r M Ch ol c c o ontevall os hales ,inc ludi ng th e a i a We1 s e t C mbr n n r quar zi te . oosa s l e C ha s .

' A r c haean Crystalline s c his ts

i n n the t givi g de ails concerning these formation s, it will be, for many reasons, mos t convenien t to consider them in t his orical order . G L Y L 3 E O OG OF A ABA MA .

C RYS T L LINE s c ms r s A . ARC H /E AN.

These rocks occupy a somewhat triangular s haped area in th e eastern part of the S tate,bounded by a l ine ru nnin g ap proximately as follows " F rom the Georgia line,near the north

' eas tern corner of Cleburne county, southwes tward through

Cl ay and Coosa into Chilton, an d th ence eastward throu gh

E lmore,Tallapoosa,Macon and L ee to th e Georgia l ine again , i about opposite Columbus . Th ese rocks difler from th e other rocks of the State in being made up of distinct, often well crystalli zed minerals, of which quartz, feldspars ,micas , an d horn blende form the great mass of the rocks in qu es tion ,whil e subordinated to these, other mineral s occ ur; either forming rock varieties of limited distribu tion, or as ores of valuable m m m w s etals,as inerals of econo ic value,or other i e of interest .

' As before stated,the great mass of these crys tal l in e rocks are aggregates of the minerals,quartz,feldspar and mica,often

' f associated with hornblende . O these the quartz an d h orn rid m m m m bl e e alone so eti es for great rock asses . Granite, gneiss, mica schist,quartzite and hornblende s chist,or slate, are th e most abundant of these rocks, while soapstones, or m s n m m m e steatites,and li e to es,are of uch ore li it d occurrence. " They are all disposed in beds of varying thickness,which are seldom in horizontal position, bu t are usu ally tilted at some considerable angle to the horizon,th e dip or slope of these beds bein g prevalently to the southeast,while the trend or strike of their upturned edges is,as a rule,to the northeast and south n m t h west . In crossi g this country fro the nor hwest to t e southeast,it can n ot fail to strike the obs erver that,as he ap pr oach es the s ou theastern border, he has evidences of con n f a A s tan tl y increas ing amou t o dec y among the rocks . long th is southeastern border they are often nothing more than stratified clays,which are the res u lt of their decay from th e ' ac tion of the atmos ph eric for ces . This decay often reaches to a depth of fifteen or twenty feet from the surface,as may be

’ d s n s een in many of th e railroa cut . I these clays,ledg es or thin sheets of quartz,which is practical ly unaff ected by th e “ weather,may be seen protrudin g ; or broken down by alterna 4 GEOL OG Y OF A L AB AM A . tion s of heat and cold, they cover the ground with angular fragments,that in process of time are worn into th e rounded pebbles that are so widely distributed over the rest of the

S tate . The conclusion seems unavoidable,that the southeast ern part of these crystall ine rocks is older,or has been longer subjected to sub - aerial decay, than the parts further to the n orthwest .

T h e Crystalline S chists,or Archaean ROCks ,have, in other parts of the U nited S tates,been arranged in two series,called

‘ H u r om an and L au r en tian ,the latter being the older of the two and presumably th e oldest rocks of which we have any knowl m edge . By so e geologists these are considered as older than an y of the stratified fossiliferous rocks,W hile by others they, as well as the H u ronian , are thought to be the altered and c rystallized sedimen ts o f the Cambrian ,S ilurian,and perhaps l ater ages . W t m d m ithou atte pting to deci e any of these atters for .

A labama,we may again recu r to the fact that th e rocks n ear

' “ th e eastern border of this region appear to be mu ch ol der ,or at least to have been very much l onger exposed to the dis in te

‘ grating action of the atmosphere than those towards the west, o r northwest,and it is almost certain that some of the rocks

“ along this northwestern border are nothing more than th e C hoccolocco or Montevallo shal es and the Weisner quartzite m m to e eta orphosed,or changed crystallin schists .

‘ l n o i — r an i Mater ia s of E co m c " al u e. The g tes and g n ei s s es m m h above na ed are used in so e slig t degree as building stones, an d deserve more attention than they have received from quar m rymen . The sa e rocks, especially the granites , which are found chiefly along a belt running northeast from near Brad ford,in Coosa county,are also largely used for the manufacture o f millstones .

r an d D ol omi —N M a bl es tes . ear Talladega and Sylacauga o ccurs a bed of good crystalline marble that ' has been worked at mb ,and e m m a nu er of localities has yi lded so e fine aterial . In L ee county, near Opelika, there is a crystalline dolomite which is white,and would make a fine ornamental and build n f m ing sto e,hardly to be distinguished ro marble . This sub stance has for years supplied the Chewacla lime works and m gives a li e of very superior quality . G Y A B 5 EOLOG OF LA A MA . — oa ~ S ps ton e or S teatite. This rock is found in several parallel n m belts runni g northeastward fro the Coosa river. It has been

e in C m o quarri d ha bers . county for the manufacture f mon

“ u ments ,headstones,and the like,and for furnis hing fir e- proof lining to the Chewacla lime kilns,for which purpose it answers . m ad irably .

“ P or cel ai n Cl ay - The decomposition of the feldspar of granites, an d other rocks,gives rise to the formation of clays which,when not mixed with other substances,are suitable for m the anufacture of porcelain and fine ware . The best kn own occurrences of this clay are near L ouina,Randolph coun ty, and S a in C N near oc patoy, oosa,and otasulga,in Macon . — Gl as s S an d There are some friable white s andstones in

Chilton county that crumble readily between the fingers,which, with proper selection, would furn ish pure silica fit for th e manufacture of glas s . — A s bes tos This su bstance occurs at various localities in

Coosa,Tallapoosa and Chambers counties,near the deposits of N corundum,belo w to be noticed . othing h as yet been don e toward the development of these beds,and it is n ot known that" x ffi t they e ist in su cien quantity to be of value . — Mi cah In some of the mica schi sts and gneisses, especially in the northwestern part of the region of the crystallin e rock s there are veins filled with large crys tallized masses of quartz, feldspar and mica,and it is these mass es of mica that furnish W e the mineral in quantity . have as yet no regular works amon g the mica veins,bu t enough h as been done to show that m mica plates of very good size can be gotten in any places . T h e ancient excavations that ar e foun d alon g the belt of coun try from Chilton to Cleburne county, mark the spots where mica has b een mined in the past, and the e xperience of th e mica miners in North Carolina goes to show that the best mica h ol d m i s. usuall y to be found by reopening t ese ines . — Cor u n du m Has been found in considerable quantity near

D u dl eyvil le,in Tallapoosa county, and also near Bradford, in C m Coos a county . That in oosa is usually very uch altered, an d it wo u ld be probably difficul t to use it because of the ff T h alteration which it has su ered . e Tallapoosa corundum m is,s o far as yet known , in frag ents,the solid bed having never been un covered . 6 Y A A BA MA GEOLOG OF L . — Z ir c on Has been found near Bradford,il l Coosa county, n n m early transpare t and well crystallized . T h e best speci ens o f s m m m thi ineral are so eti es used as gems .

Gr aphi te~ l s widely disseminated in small quantities in many of the crystalline rocks,sometimes impregnating alum in ou s slates to such an extent as to render them suitable for l i m m ubr cating purposes . S o e very fine sea s of graphite have recently been found near E n itach opka,in Clay county,and it is probable that it will be found in other counties in sufficient u ffi q antity and of su cient purity to be valuable .

Gol d - Most of the gravels and sands of this region have

" in the past been profitably worked for gold . Arbacoochee,

Ch u l ifin n ee,Pinetucky and Goldville are well known localities .

F or many years,however,this kind of work has ceased,and s o has the working up of the quartz in stamp mills . There is r eason for thinking that, with the new processes for the e xtraction of gold from low grade ores,many of ou r ores can T h yet be worked with profit . e geological survey is at present engaged in , the investigation of these processes in

K= = con nection with the Alabama gold or es . — m n Capper . The history of the copper ini g in Alabama is S m d s imilar to that of gold . o e years ago a good eal of money was invested in a copper mine in Cleburne county,and the ore wa works flourished until the rich surface s used up . The

’ mu n dic or main body of the vein , containing only a small d percentage of copper, coul not be profitably s mel ted, on I a u n of m cco t distance fro lines of transportation, etc ., and m work there has been suspended for a nu ber of years . Cop m per is known to occur in very any localities in this region , bu t the mine above named is the only on e wh ere any system f atic work has been done o late years . — Man gan es eZ Although man ganese is very extensively dis tributed through this region,no large deposits of it have ye t b een found . — m a I r on Or es . The i port nt iron ore of th e crystalline rocks is Mag n eti te,and it has been found in most of the counties of this region of the State, but n ot, so far, in great quantity, a h h m lt ough searc has been very persistently ade for it . Good

* A b u l l eti n (No . 4) o n t h e lower po rtio n o f th e gold regio n h as been publis hed wa a s s inc e th e above s in m nu c ript . A 7 GEOLOG Y OF A LA BA M . sized fragments of magnetite,in dicating a bed of considerable k n C u C Ra Ch m thic ness,have,been fou d in leb rne, lay, ndolph, a i n bers and Tallapoosa counties . Talladega county there is a sandstone impregnated with magnetite to such a degree as ir almost to make it a wor kable ore of On . — 1 1 c mc ut e or Specu l ar Or e Is also common in many of the rocks of this region ,but no large beds of it are yet known . — “ L i m on ite I S also abundant in many cases as gossan, m f m . S i . e.,the result o the deco position of pyritous ores o e of the limonite, however, which was once used in the old

Catalan forges appears to be of a diff erent kind . In all the region where the rocks are partly or entirely composed of horn blende,these iron ores of various ki nds are more or less abundant .

- E n or P yr i te. xte sive beds of iron pyrite pyrites are known S not in Clay county,of this tate,but have yet been worked . Most of the copper or e of the S tate is pyrite with a certain con cen tr atl n percentage of copper . In g these ores, the sul phur of the pyrite is allowed to go to waste . In the E nglish in m works, this is u tilized . anufacturing sulphuric acid, the profit upon which alone pays well,whilst the copper and also ffi the iron are pure gain . With capital su cient to provide for manufacturing sulphuric acid, copper works will be made to pay a much greater profit t han they do now . In view of the recent discoveries of phosphate in F lorida,it might be well to take into consideration the possibilities of our pyrite beds as n m for m fu r ishing aterial the anufacture of , sulphuric acid,

- used in the production of super phosphates .

R u ffl e or T i tan i c A c i d- m of , Is a ineral very general G s eCl m n s m m occurrence . ood p e have co e fro Coosa and Chil I ts ih m ton counties . uses the arts are li ited,but its value as a cabinet specimen ,well crystallized, will command a ready sale . — m Tan tali te. This rare ineral has been found for the first S C time in this tate,in oosa county,near Rockford . The anal

- L S m L ys is of it,by J . awrence ith,of ouisville,Ken tucky, was h il l publis ed the first edition of this book . — B er g/L This mineral has been obtained from Coosa county m m in c rystals,which have yielded very handso e ge s when ou t . 8 GE OL OGY OF A LA BA MA .

PA L E Z l F T O O C O RMA IO NS .

— Cl as s ification an dL ith ol ogical Char acter s The geol og ic al formations of th e above list, from Carboniferous to the

Cambrian inclu sive,have been grouped together in on e divis ion ,cal l eu P al eozoi c (an cient life) ,in all u sion to the want of resemblance to the present existing forms of the animal and plant remains contained in them .

' In the fol l ovvin g account Of the distinguishing characters of the rocks of each of the great groups of formations Cam br ian , S il u r i an ,D evon i an and Car bon if er ou s ,which constitute — the Paleozoic we shall follow pretty closely what h as already

- been printed in the report ou the Cahaba coal fields . — T h e Cambr ian The rocks of this formation are con glomerates ,sandstones and shales in the Coosa valley region, and shales and shaly limestone in the valleys further west,the maximum thickness of the whole being put at feet ; but th is great thickness is seen only in the eas tern part of the

Coos a valley . In the other valleys the thickness is less than half of the above . The subdivisions of the Cambrian which we recognize in

Alabama are as foll ows The Coosa shales ,the Choccolocco or

Montevallo shales,and,interbedded with the last named,the

Weisn er quartzite . These subdivisions are based rather upon the lithological characters than up on the ch ronological succes sion ,which cannot at this time be given with certainty,for the calcareous shales,which we class with the Coosa,have recently been found to contain upper Cambrian fossils ,while some of the shales of the Montevallo type have yielded lower Cambrian n m M fossils . O the other hand,so e of the ontevallo type of shales may be seen in places immediately underlying the strata of the Knox dolomite,while in other places the Coosa fl tw od m or a o s type of shale has apparently the sa e position . It is very probable that the difi er en ce in the composition of — — e. h the Cambrian shales i . ,w ether calcareous or sandy is du e to the geographical and other conditions existing during their time of deposition , and that both kinds were formed — contemporaneously a part near the shore line ; a part further 9 GEOLOG Y OF A L A BA MA .

t t h e C a out to sea . In cer ain parts of oosa v lley,where both types of shales occur togeth er, the calcareous shales of the Coosa type appear very " generally to u nderlie those of the

~ siliceous or Montevallo type . — Coosa S hak a I n the valleys above mentioned,the rocks of this division are thin bedded limestone,with clay seams between— usually very greatly contorted and tilted at high

n m a gles . t ere these rocks co e to the surface,there results

/ ' ‘ from their decomposition a very s tifi calcareous clay soil .

These lands being very level,and hence very badly drained,

’ are n ot mu ch c u l tivated in Alabama,and are generally known as The shaly limestones that give ris e to these

flatwoods we have called Coosa shales . — 0 M on teval l o S h ak a Ih the Coosa vall ey ,an d es pecral ly in ’ its eastern parts ,and in the southwestern part of the Cahaba valley, towards Helena and Montevallo,we find a considerable thickness of siliceous or sandy shales of great variety of colors , such as olive green , chocolate, yellowish, etc . The original m aterial was a calcareous matter has mostly been pretty m thoroughly leached out, and only the ore siliceous parts left . These s hales crumbl e u p in places to small fragments abou t m m m th e size and shape of s h oe p eg s . So eti es they are ore tough , and, especially towards the east, assume gradually the characters of the semi- crystalline rocks, and it is capable of demonstration that some of the partly crystalline slates of the eastern part of the Coosa valley are only the ch anged or meta morph os ed representatives of th is division , which h as been called the Mon teval l o or Ch oc c ol oc c o s hal es ,from the character istic occurrences in those localities . In the upper part of the Montevallo shales we find beds of blue limestone and gray dolomite,which it is often difficult to distinguish from the

m m -i si ilar rocks occurring in the next overlying the for at on .

In fact,the line between the shales an d the K nox dolomite is,

A m d an n so far as laba a is concerne ,rather arbitrary o e.

r — I h Wei s n er Qu a tzi te. the shales j ust described,and most commonly in their lower parts,are found in the eastern part C f m of the oosa valley great beds c quartzite and conglo erate, many hundred feet in thickness,but often of very limited ex h tent geographically . T e quartzite always forms h igh and rugged mountains,sometimes stretching for miles in an u n 1 0 E A A A G OLOG Y OF L B MA . broken range,but as often forming detached an d isolated peaks rising suddenly ou t of the plains and as suddenly sinking down m “ m ” m to the sa e level . The ountain near Colu biana, the

Kahatchee hills,Alpine mou n tain,Mou nt Parnassus ,at Talla dega,Coldwater mountai n and Blue mountain ,near Anniston , W the L adiga mountain, above Jacksonville, and the eisner mountain,east of Jacksonville,are instances of occurrences of W m this q u artzite . The eisner mo u n tain has been ost studied, and its s tratigraphical relation to the Coosa shales,and to the

Cho ccolocco shales,most clearly made out,for which reason we have used the term Weisner qu ar tzite m to designate this h i ember of our Cambrian , which occurs interpolated in t e m f shales ,as local asses of lenticular shape,often o very g reat thickness . P S ff of n m C e rof . a ord, Te nessee,has given the na e hilhowe to similar great masses of sandston e and quartzite occurring in

P . that S tate, apparently below the shales above named . rof S afi ord places these sandstones always bel ow the shales,but this does not seem to be their position in Al abama, as the masses of sandstone occur at diff erent horizons, interbedded

F r n t P . S af with the shales . o this reason we have o used rof ’ ford s n ame . S m n eces _ to designate the rock i ilarly,it appears sary to adopt a distinct name for the thin - bedded limestones “ ” with clay seams, of our flatwoods , since they play a very l subordinate part,if they occur at all in Tennessee . In genera the Choccolocco and Coosa shales ,as abo ve defined,are partly, at least,th e e equ ival en ts of the K n ox sandstone and shale of

Tennessee,but ap parent important differences in th e strati graphy of these beds,in the two S tates ,make it impossible as yet to correlate them strictly,hence ou r adoption ,provisionally at least,of diff erent names . — T h e Sil u r ia n W e have not yet, in Alabama, found it practicable to arrange our S ilurian formation in more than three principal divisions,which ,beginning at the lowest, and coming u pward, are as follows " K n ox dol omi te, T r en ton or

R e M ou n n r P ell i am l i mes ton e,an d d tai o Cl i n ton . — n S f r K n ow D ol om i te This ame has been given by D r . af o d to a series of rocks occurring in th e vicinity of Knoxville,Ten m n es s ee,and inasmuch as the rocks of this horizon in Alaba a

are identical with those described by him,we have retained 1 1 GEOLOG Y OF A LA BA MA .

the m h m im na e in the Alabama survey . T is is one of the ost portant and widely spread of ou r older geological formations , and its c haracteristic rocks are magnesian l imestones,or dolo

mites ,sometimes quite pure,but more often impregnated with m m t d siliceous matter . This siliceous atter is so e imes foun as

a sandy impurity in some of the dolomites,upon the weather F or ing of which it becomes quite prominent . this reason many of the dolomite beds of the lower part of the Knox dolo

mite, when exposed to the weather, show a rough and sandy

surface,marked by shallow cracks running in every direction , as if the rock had been hacked or gashed by some cutting in m strument . These purer and sandy dolo ites, together with

some beds of tolerably pure blue limestone,occur near the base

Of th e Knox dolomite,and are very closely related to the beds “ of the shale division already described) On the other hand, the siliceous matter in the upper part of th e formation is usu

ally found ih masses of chert, of concretionary origin ,impreg

nating the dolomite,and on the breaking down of these rocks,

under the action of the weather, the calcareous parts are

leached out,whi le the siliceous parts usually remain in the

form of angular,flin ty gravel ,which forms the very character of m istle ridges of Knox dolomite . The weathering the li e

stones and th e dolomites, near the base of this division ,has given rise to the formation of gently undulating terranes,with

a deep red - colored sandy loam soil,of more than average fer

til ity,which is the base of the best farming lands in all these E t Bir min valleys . The red lands about lyton ,and in par s of g

ham,and in the Al exandria valley,across the Coosa,are good I n m examples . the upper part of the dolo ite the cher ty,or

siliceous matter,is more abundant as a surface material than

thecalcareous,and the coun try is broken or ridgy,rather than

undulating . S ome of these flint ridges extend for long dis G m h tances unbroken . ood exa ples are the ridges of the nort h h and sout ighlands about Birmingham . In fact,this angular, cherty gravel is found upon all the lands made by the Knox dolomite,but is much more abundant and characteristic in the

upper part . The Knox dolomite con tains very few fossils,and these belong to the lower Silurian horizon of the pal eon tol o

Rec ent inves tigation appears t o s how that part of th es e limes to ne beds belong , in al l probability,to th e Cambrian formatio n . 1 2 GEOLOG Y OF A L A B A MA . gists ,but we have in th e chert itself a characteris tic by which m we c an , as a rule,distinguish it from the c hert of other for a — tions that is, in most of it are small, angular cavities of clearly defined shape,which are usually thought to mark the . u b place once occ upied by rhombohedral crystals of . dolomite,s

' ff was th e r sequently dissolved ou t . Prof . S a ord fi st to call m atten tion to this mark,which we have found to be an extre ely fi" t useful on e The K nox dolomite,as well as the upper . par of m the underlying formation ,seems to have held originally uch u ferruginous as well as sil iceous matter, and thro ghout the region formed both by the dolomite and the upper part of the shale,occur the beds of the brown iron ore,or limonite,which play so important a part in th e econ omic h is tor yo f al l this m region . The iron or e seems to have been derived fro these l m older rocks . A s instances of the occurrence of i onite banks connected with the dolomite an d shale,I may men tion the E d wards ore bank , near Woodstock, the mines at Greely and

Goethite, in Jones valley,an d the g reat beds at S helby, over f m the Coosa . The great bulk o the brown iron ores of Alaba a is from t his horizon .

At th e top of the Knox dolomite, and belonging perhaps to the ne xt, s u cceeding division ,there is rather a peculiar rock h i occurrin g at intervals along Jones valley and elsew ere . It s a br ec ci a,made up of angular fragments,chiefly of th e chert of the Knox dolomite,cemented together into a rock which is a m good many feet in thickness . This rock,being ade of frag ments of th e Knox dolomite,is ,of course,younger, though ,on

account of its materials, we have usually classed it along with m the Knox dolomite . It is seen in the greatest volu e in the

Salem hills,southwest of Bessemer,but occurs upon th e flint

m m e ridge for ing the north highlands at any points , . g ., Bir min h m G S g a and ate City,and also west of pringville . It has

B i r m n h am br ecci a Mr been called the i g by . Russell of the

U ni ted S tates survey,and S al em br ecc ia by us in the S tate v of a sur ey . It is interest as showing that period of disturb ance intervened b etween the time of th e formation of the m and m Knox dolo ite that of the Trenton li estone . — T r en ton or P el li am L imes ton e As its name implies,this

S imilar angular c avities have rec ently been Obs erved in th e dus t of o ther form

at ion s ,s o that this is n o t an alto gether c harac teris tic mark of th e dolo mite . A A BA A 1 3 GEOLOG Y OF L M . d m ivision is ostly calcareous . It may be perhaps,as a maxi mu m, 800 feet in thickness , and varies considerably in quality, th e lower part being usually impure and shaly , while the upper part is mostly apu re limestone, often used for th e pur oi m m pose aking li e and as a flux in the furnaces . The lower part usually holds great nu mbers of shells o f Macl u r ea mag n a, a characteristic fossil of the Chazy limestone of the N ew Y ork

“ geologis ts . The purer limestone above 1 s also quite f ull of fossils ,which,as a group,are those of the Trenton limestone f o New Y ork .

In places ,particu larly in the region south of the Cahaba

' field in Bibb county, the u ppermost beds of this formation , above the purer limestone mentioned, are calcareous shales and shaly limestones,often full of the fossil forms known as

r l W m g apto i tes . here these thin bedded shaly li estones form the surface they make cedar glades . The valley between th e Cahaba and Coosa coal fields shows a wide belt of Trenton limestone,wh ich is particularly pure and well developed near Pelham and S iluria,in S helby N P ’ county,and southwards . ear ratt s ferry , on the Cahaba, and,stretching thence northeastward, there is another great

" belt of it,containing some fine marbles ,which have,in a small ’ degree,been worked at Pratt s ferry . — Th e Cl i n ton or R ed M ou n tai n F or mati on This is the third and uppermost of the divisions of the S ilurian which we m f make in this S tate . The ass of the rocks o Red moun tai n

‘ are sandstones an d shales,which show agreat var iety of color, yellow,red,brown , chocolate and olive green ,in this respect A n i h resembling th e Mo ntevallo shales . lo g w t these are some calcareous and ferruginous rocks,the latter passing into beds

' ' m of red iron or e,made u p of s all flattened nodules ,shell casts ,

- / i . man l aces m etc .,o ferric oxide In y p where ining has pen e m tr ated the or e bed beyond the reach of at ospheric agencies , the ore is seen to be quite calcareous in fact,a kind of highly ferruginous limestone,which ,w hen used in the furnace,often A t contains lime enough to flu x itself . the outcrop the or e is S o seldom calcareous, though Often sandy . far as I know,

" there has been no very satisfactory explanation of the mode of of formation of this ore . It is a very variable thickness,up to twenty feet,and is in more than one bed . It is a remark 1 4 BA GEOLO GY OF A L A MA .

able fact that, while near Oxmoor the ore is some twenty feet

in thickness,j ust across the Cahaba coal field,in the Cahaba

valley,about six miles distant, the Red mountain ,or,rather, f its representative,contains no ore at all in the greater part o

' its length ,n or does it seem,except at intervals,to contain any

of the Clinton rocks,bu t only those of the D evonian and sub m s carboniferous . As is well known, this for ation furnishe the greater part of the material used in our furnaces In

places, the ferruginous limeston e of this formation wou ld

make a fine building stone,an d the same is true of the sand t to v th e a c stones . I would be diffi cult gi e aver ge thi kness of the Red mo u ntain rocks proper ; 1 00 feet might perh aps be a

fair average,for the Red moun tain ,as a topographic featur e, m of a — o C is ade of the rocks , different ges Trent n , linton and

sub - carboniferous,together with the usually very thin black

shale of the D evonian .

“ The thicknes s of the whole S ilu rian, as usually given at m about feet,is only an esti ate . The true thickness it

would be very difficult to determine,especially in the case of the mos t important member,theK nox dolomite,since it is in m s o great part ade up, far as surface materials are concerned, of loos e fragments of chert in which the bedding planes are

seldom to be seen . A greater part of the area of our valleys

is held by this formation than by any other,and its impor

' tance is still further enhanced by the fact that it is th e chief

th e n S . M source of brown iro ores of the tate any . of the e “ ri s m not d big sp ngs is ue fro this formation . “

~ T h e D evonian . - The only representative in Alabama of this system of rocks , which in the S tates further north is of m n great thickness and i portance,is a thi bed of bl ack s hal e, averaging perhaps ten or fifteen feet, but being apparently m absent altogether in so e places . A few fossils have been of N found in it in the valley the Tennessee in orth A labama, o m m of which serve to fix its p sition as a e ber the D evonian . t m The shale,being sof and so ewhat easily eroded, is usually Of covered and concealed by the debris the adjacen t rocks,so that it does not commonly come under notice even where it is m present . It is of i portance chiefly, perhaps, as being the of m of source so e our best known sulphur springs . The s hale usually contains a large amount of pyrite in the form of

| 6 A L A BA A GEOLOG Y OF M .

Knox dolomite enable us ‘ in almost every case to distinguish between the two .

Now,in the anticlinal valleys south of the Tennessee river we find it impossible to carry out this t wo - fold division of the lower or siliceous member of the sub - carboniferous, for the entire member shows,upon the surface at least,little else than m chert,which appears in a mantle of angu lar frag ents,cover ing usually on e side of all ou r Red mountain ridges . W e have called this the F or t P ayn e c her t,and it is prob ably th e representative of both sub - divisions of the lower

‘ ‘ sub - carbonifero u s o r siliceous g l Ol l p of north . Alab ama and

Tennessee,as long ago conj ectured by Professor S aff o rd . Its thickness is net very great, as compared with that of the * upper member .

The upper calcareous member is variable in composition . In north A labama it is chiefly limestone— called mountain limestone,from the fact that it forms the flanks of most of the w m mountains in that section that are capped ith coal easures . W ithin this limestone there is in terbedded a layer of sand — stone of variable thickness perhaps 1 00 feet,at a maxi mum, in the Tennessee valley,while the over and underlying lime m m w stones are many ti es that . As we co e south ard the sandstone becomes more important, and the lower section of the limestone (below the sandstone) appears to give way to,or to be replaced by,a series of black shales closely resembling D m m r e im m those of the evonian , but any o t es assive . In

' many places in the anticlinal valleys ,and especially the furth er south we go, the upper limestone also appears to b e wanting or to be replaced by the shales and sandstones above named . The limestone which comes next below the coal measures is well exposed at many places,as at Bangor, Blount S prings and Trussville,where it is very extensively quarried for use as a flu xin g material in the f u rnaces,as it is in part a very f pure limestone . But south o the latitude of Birmingham it is very rarely seen,and in its stead we fi n d the b lack shales t in mentioned. These shales are of en ters tr atified with dark

at I n th e a c al valle s e e ma s a b e s e nti lin y th r y u u lly en between th e Red mo untain

an d th e o f th e valle a a o s u b - va l ridges rim y n rr w l ey with very go o d re ddis h loamy

ea a a s c va o . T s s o ma b s oils ,n rly lw y in ulti ti n hi il y e in part derive d fro m th e ro c k s f th e S t . L o s o of th e s c eo s o os s o ui gr up ili u , th ugh p ibly from t h e s hales o f th e

Ox oo o zo . We ave o n o o ss s to e e e o m r h ri n h f und f il d t rmin this p int . Y 1 7 GEOLOG OF A LA BA MA . colored limestones,and so metimes with tolerably pure lime ston es, but these are uni mportant in thickness as compared with the shal es and sandstones . The greater part of S hades valley is based upon these sandstones and shales,though the l imestone appears in several places, and southwestward,be yond the end of the Cahaba coal field,these rocks make a very prominent topographic feature . The sandstone which in north Alabama lies between the two beds of mountain limeston e has a very close resemblance in texture and other characters to the lowermost rocks of the coal measures , commonly called the millstone grit, and it makes its appearance in that part of the S tate either as a bench along the sides of th e Cumberland mountain spurs or else as the capping and protecting rock of a detached ridge separated from the S and mountain (coal measures) by a narrow valley of erosion . In the anticlinal valleys further south, this s andstone with the lithological characters above named appears commonly as a distinct ridge running parall el to the escarpment of the coal measures,with a narrow valley to of shales between . It appears best advantage on one of the detached ridges above spoken of,near Tuscumbia,at th e site of the old college town of L aGran ge,and we have often used th e name L aGran ge sandstone to designate it ; but the name L aGrang e has been used to denote an entirely diff erent formation, which has caused us to replace it by the name

Oxmoor,where the rocks are also well exposed and where the shales are more conspicuous than at L aGran ge. — m Coal Meas u r es . The strata of the coal easures are sandstones,conglomerates,shales and coal beds in many alter nations, and at on e horizon , at least, occurs a thin bedded th e m C limestone . The thickness of easures of the ahaba coal to field is estimated by Mr . S quire be feet,and the esti M Cal l e mate for the Warrior field, by Mr . c y, is about the c o f same . The conglomerates are found prin ipally at the base th e measures,though a very h eavy bed of .this rock occurs also d T u kaloos a at the top of the meas ures in Shelby an s counties . W e have good reason for thinking that all our coal fields were at one time continuous an d have b een separated by subs equent l d — changes into the three distinct fie s named by Prof . Thomey ' — from the rivers which drain them the Coos a, Cahaba an d 1 8 O Y A A B A A GEOL G OF L M .

War r i or . W e . find fields should expect to the _ succession of the coal seams and of other strata the same inall three fields, and undoubtedly su ch a similarity or equivalency will one u h m ou r day be thoro g ly ade out . At the present,however, knowledge of the fields is so limi ted that it is n ot possible to

‘ corr el ate th eir s eams fully,though some identification s have m been very satisfactorily ade . t h al l e on In e reports of Messrs . S quire and Mc C y the Cahaba and Warrior fields full particulars will be found con cerning these fields,and the reader is referred . to these reports i r ' n d b for information as to details . In the W arr o a Caha a

fields there are about forty coal seams,of which twelve to fourteen have a thickness of two and a half feet and upwards , f M o coal,which can be profitably mined . uch of the coal, however,which is actually mined n o w comes from a much m l ace ' we s aller number of seams . In another p shall give a few particulars concerning each of the three fields above named .

GE O GRAPHIC AL D IS TRIBUT IO N IN ALA BAMA O F T H E PA L O Z O C FO RMAT O E I I NS .

mm It is a co only received Opinion among geologists,and one capable of demonstration,that the older stratified rocks of th e A ppalachian region of th e U nited S tates, of which the P m m aleozoic rocks of Alaba a for the southwestern termination, are formed principally out of the detritus of a previously ex is ting land area lying eastward of th e present shore line of the Atlantic ocean ,washed down and deposited upon the floor of the inlan d sea,which formerly occupied the greater part of N what is the present U nited States . aturally, by far the greater part of this land was te w ou l d be deposited close to the shore line, while only the finer sediments, such as silt and mu d,would be h eld in suspension long enough to be carried m t h e out and deposited at a distance fro shore . As a matter of fact,in Alabama,in going from the northwest to the south m east, across the region ade by our Paleozoic rocks,we find a ‘ A A BA 1 9 GEOLOG Y OF L MA .

gradual increase,not only in the thickness of th e strata, but in the coarseness of the material ; heavy bedded sandstones an d conglomerates being much more abundant in the eastern pa rt m m m h of this area than farther west . The axi u thickness of t e

Paleozoic rocks in A labama, along their eastern border,is n o t l eSs than feet,but further westward it is probably n ot f h much more than half this amount . After the deposition O t e ’ Carboniferous strata,there followed movements of the earth s crust by which all these Paleozoic deposits were elevated above the sea,and pressed or squeezed laterally from southeast to northwest into a much narrower space th an they occupied m when spread ou t u pon the floor of the sea . This co pression into narrower limits could take place either by the crushin g together laterally of the beds and their corresponding swellin g up vertically ; or by the warping of the strata into more or less closely folded waves or wrin kles running at right angle s to th e direction of the compressing force ; or by fracture alon g the same line at right angles to the compressin g force,and the slidin g of on e part of the strata over another . It is easy to recognize in Alabama instances of all these results of compres sion ; for we find our Paleozoic rocks seldom in their ,original position ; they are mostly tilted at high angles to the horizon the same beds are repeated many times,and sometim es strata are n ow found in juxtaposition which are many hundreds of feet apart in the geological column . The direction Of the dip of these tilted beds is mostly to wards th e south east,and the amount Of the tilting and deformati on is greater in the same direction , gradually diminishing in intensity as we go north A n n i nd1 cated west . fter the uplifti g,faulting and foldi g above , there began a gradual degradation of the strata by atmospheric h m d m m agencies . T e places ost elevate by these ove ents,o r s u ff er m most weakened by fracture,would ost by these mean s . S O th e we find, as a rule, valleys now occupying , what were formerly the crests of th e folds or waves Of the strata,and it is consequently in these valleys that we find exposed the lowest or oldest rocks in the s eries,and the depth of the exposure in proportion to the amount Of the previous elevation .

In accordance with these general principles,we find that the oldest of our Paleozoic rocks have their greatest develop ment as surface rocks along the eastern border of the region of 20 GEOLOG Y OF A LA BA MA .

e. . their occurrence,i . ,in the Coosa valley region Here also we find the strata most disturbed and deformed, while the

‘ rocks of the Clinton ,D evonian, or Carboniferous formations n occur sparingly in th e Coosa valley,except along its wester m t f li it . It is only o the westward o the Coosa valley that these upper strata of the Paleozoic formations are widely d distribute . The areas of ou r coal measures are separated by val leys,in which the older rocks are exposed by den udation as above described . All these valleys have what is called the anticlinal f e. o structure,i . ,they have been eroded out of the crests folds in the strata ; but this structure is generally obscured by the occurrence of faults where the beds onone side of the line of fracture have been pushed up over on those of the other . These valleys are,in succession,going to the northwest " The Cahaba

' val l ey, lying between th e Coosa and the Cahaba coal fields ; ’ ’ Will s val l ey,between L ookout and S and mountains ; R ou p s ’ and J on es vall ey,between the Warrior an d Cahaba coal fiel ds ; ’ ’ M u rpl i r ee s vall ey,which i s a prolongation of Jones valley and ’ separates two parts of S an d mou ntain ; and B r own s or B ig

Spr i n g vall ey, extending down fromTennessee,as a prolonga tion of the S equ atch ee valley,separating likewise two parts of

- m f the Warrior field . In the last na ed valley,south o the Ten n es s ee river,the sub - carboniferous rocks form th e greater part h n of the surface, and t e u derlying and older rocks are exposed N o n ly in isolated tracts . orth of the river,the elevation of the fold has been greater,and the consequent exposure, by erosion of the valley , deeper . In the Tennessee valley likewise, the

- t sub carboniferous rocks occupy the greater par of the surface .

E ach of the valleys above enumerated has its peculiarities,but to go into details would lead us too far . W e may,however, add a few words to what has already been said about the coal

fields . Mater ial s of E conomi c " al u e in th e Pal eozoic Reg ion" — m Coal . The Alaba a coal fields, occupying, as they do, the t h e m troughs between folds or wave crests above entioned, are more or less basin - shaped,bu t the axis of the basin in each case lies close to one side,usually the southeastern ,instead of being in the center,and the slope or dip of most of the strata is consequently towards the southeast . In going from the north G A A BA A 21 GEOLO Y OF L M . east toward th e southwes t,we find the strata of th ese fields n S n m gradually sinking . Thus,o a d ountain ,near the Georgia line,the base of th e coal measures is six or seven hundred feet above drainag e level, especially alon g the elevated r im of th e basin,whil e at T u s kal oos a,the base of these measures lies F r n n feet,or more,below drainage level . o co venie ce, we have designated those parts of th e coal fields which are high above th e dr ain a e l ateau r e i on d , g level, as the p g , in contra istinction

bas i n r e i on to the g ,where they are at or below drainage level , This distinction applies mainly to the Warrior field an d L ook ou t mountain ,the Cah aba and Coosa fields having measures generally below th e drain age level ; but a gradual southeast n m a m si king of the e sures is very clearly seen in the also .

Th e Goos u F i el d - This h as less of what are called the flat measures than either of th e others . It has suffered most from denudation , and h as th e least thick n ess of coal measures, an d consequently of coal seams ; nevertheless,two or three seams of workable size are kn own in the field,and mines ar e in opera — tion in two or three localities Broken Arrow, Ragland,Trout T h e cOal m t Creek ,etc . rocks and sea s in his field appear to be more faulted than in the others .

F i el d— i T he Cah aba. Th s field has been recen tly thoroughly described by Mr . S qu ire, and his report is accompanied by a

ma . m large and detailed p It extends fro Canoe creek ,in S t .

Clair county,to H ays op creek ,in Bibb coun ty, its form very closely resembling the human foot and leg, Mon teval l o bein g close to the heel, and th e part repes en tin g the toe being on m w H ays o p creek, four or five iles est of S cottsville . The field begins t o widen at H elena, an d opens out gradually as it con tin nes southward until it attain s a maximum width of fifteen mi an d a half les,on a line due east and west from Blocton , The

" leng th of the field on an air line is sixty miles,and its area M m . r S about 390 square iles . quire describes eleven s u bor di nate basins in this field,besides the overturn ed measures at

s ou th er n en d of . the ’ the field In consequence of the gradual dip of the basin as a whole toward the southwest,the greatest thickness of the meas u res in this field is foun d in the sou th A m n ow n western end . ctive ining is goi g on at Blocton,Gu r nee, Montevallo, Helena and Hen ry - E llen ,th e seams worked being " At Blocton, the Thompson , or U nderwood, and the 9- 2 GEOLOG Y OF A LA B A MA .

m Woodstock seams ; at Gurnee,the Clark and Gholson sea s ; W h at Montevallo,the Montevallo seam at Helena,the adswort

Mr . m . an d Helena seams ; at Henry - E llen , the Mammoth sea S quire estimates that this field has eleven seams of coal over t wo and a half feet in thickness, aggregating forty feet of m arketable coal . Coke is made in large quantity at Blocton a n d other mines in this field . — War r i o r F i el d The area of this field is estimated at about s square miles,and th e thickness of the measures varie with the localities, it being only a few hundred feet in the n ortheast part of the plateau region , and nearly feet at m m the southwestern end of the field . The nu ber of coal sea s

Mr . M al l varies in the same sen se . c C ey gives about forty seams in this field,fourteen of which are two an d a half feet e m m n and upwards in thickness . The localities wher ost i ing is done are " Pratt Mines , Mary L ee mines , and others near , m m C m n em Bir ingha ; Blue , reek i es, below Bess er ; several mines at Newcastle and Warrior,in Jefferson county ; at Cor dova,Horse Creek ,Carbon Hill and Corona and other localities in Walker county ; Brookwood and Coaling, in T u s kal oos a F r d d d county . o etails concerning the fiel ,the reader is referre

r l W to the report of M . Mc Ca l ey on the arrior basin of the m f r plateau l egion . Coke is ade in the largest quantity Om the coal of the Pratt, Blue Creek,Mary L ee and Brookwood mines .

- C Red M m n Red I r on Or e. The linton or ountain for atio d f carries a varie thickness o red fossiliferous ore . This forma tion occurs on the ridge on each side of the anticlinal valleys above named,and in each of these, at on e or more points, the ore is of quality and quantity which make it of commercial i mportan ce . The great bulk of this ore m ined in Alabama comes from Red mountain ridge, alon g the eastern side of m R ’ Ga G Jones valley,fro eeder s p to ate City . At on e place r e m the o is twenty feet,or ore in thickness . On the west side of Mu r ph rees valley,along th e western border of the Coosa valley above S pringville,and at Attalla near the base of L ook o u t mountain,and along the eastern foot of L ookout at inter v R u m x i als up to o nd ountain ,the ore is also e tens vely mined . — B r own I r on Or e This ore is usually associated with the strata of the lower S ilurian ( Knox dolomite) an d the upper

24 GEOL OG Y OF A LA BA MA .

t S prings,in D eK al b county,but occurs in small quan ities in several localities in th e s nb - carboniferous formation . — Man g an es e Or e Like th e brown iron or es ,is usually found

' associated with the sub - carboniferous or the lower Silurian

e. . T u C beds, g ,in Blount, s kal oos a, S t . Clair, alhoun and other counties,but it h as nowhere yet been found in sufficient qua n mm tity to be of great co ercial importance . — S an ds ton e F or building purposes has been quarried from the strata of the coal measures n ear Cullman ,from the Clinton formation in Wills valley, and elsewhere from the Cambrian m m n for ation in a y localities . — S i cl er i te or Spathi c Or e,or Cl ay I r on S ton e Is common th e m n ot in coal easures ,but as yet mined .

B l a k B . c an df Is also n ot uncommon in the same formation B — m au xi ter . This i portant mineral, used as a source of metallic al l u min u m,is n ow being shipped in large quan tity

’ m n . fro Cherokee county . It is associated with the brown iro O ores of that region . ther occurrences are known in Calhoun county .

MES O Z OIC A ND C E NO Z OIC FO RMAT IO NS C RE T A

C E O US AND T E RT l A RY .

' After the accumulation as above described and the eleva vation above th e sea of the sediments which make up the

Paleozoic formations,they con stituted the land area of Ala m ba a . This ancient land area was in the northeas t part of the S tate, its gulf border bein g then along a curved line m t n th passing fro the nor hwest cor er of e S t ate, thro u gh F ayette Court House,T u s kal oos a, S cottsvill e,Centreville and D W etumpka,to Columbus,Georgia . uring the next following geological periods, which have been named Cretaceous and

Tertiary,this land mass, disintegrated by atmospheric agen m cies,furnished the aterial which was carried down by rains, rivulets and rivers to the gulf and spread upon its floor in the

’ form o f beds of pebbles and coarse sand n ear the shore and in the s hallow places, in the form of fine sand and clays in the 2 0 GEOL O G Y OF A L A BA MA . deeper parts an d farther from the shores,while in still deeper waters ,not reached or only partially aff ected by the washings from th e land,flourished the corals an d other marine animals which formed the limestones . D uring all this time there was a g r adu al el evati on of the land— varied at intervals by periods of rest and even of down — ward movement in striki n g contrast to the manner in which the Paleozoic deposits were elevated and compressed together, m folded and faulted . The result of this ovement was to tran sfer southward , step by step, the shore line of the gulf and to add to the dry land, in successive belts , the sediments

m n h of which had accu ulated alo g the coasts . As eac belt these deposits was added to the dry land, it,in turn,was sub j ected to erosion ,and contributed its share to the materials carried down by th e streams an d deposited upon the bottom of the sea,to form the strata of the newer formations,them

i n m m fir m selves ti e and in si ilar way to be added to the land .

F rom this acco u nt,it will be seen that our Cretaceous an d Tertiary formations con sist of strata h aving a ge ntle slope toward the south and coming to the surface,or outcropping, — in approximately parallel belts across the State th e oldest beds farthest north and the n ewer beds occupying the surface, on e after the other,as we go southward in the order of their relative age . By making careful examinations and measurements of the various strata,as exposed along ou r rivers,in gullies and other natural sections,an d bv making use of the reco rds of artesian

’ borings,the quality and thickness of the sediments of these

m n m . ,two for atio s have been worked out with so e accuracy . If all the strata cOu l d be penetrated by a single boring,we should find about feet of them belonging to the Creta ceou s ,and some feet to the Tertiary,an d we should also m be m m fin d. as ight expected fro their ode of deposition , that / the greater part of these sediments consists of sands inter s tr atified wi th thin sheets and,in some instances ,with thick beds of clay . i At two hor zons ,viz " in the u ppermost of the Cretaceous and at th e top of the Tertiary also,we find important calca ’ r eou s deposits,the rotten limestone of the Cretaceous, which forms the basis of our prairie lands, being about feet 26 E Y G OLOG OF A LA BA MA . thick, and the white l imestone of the Tertiary, which al so ms or m I n for prairie li e lands being 200 or 300 feet thick . the eastern half of the State one of the lowermost of the m Tertiary beds is a li estone . Among the sandy strata of the Tertiary we find several important beds of marine shells which can be used as marls, and also beds of lignite or brown coal,which,though small of value as fu el ,h as recently bee n f ound to be the bes t material to be us ed in the clarifying of sugar ; —At Cr etaceou s . the bottom of the Cretaceous, we find about feet of clays and sands, more clayey below and sandier above,constitu ting what h as been called the T u s ka ‘ o l o s a formation . Thes e beds are much thinner,going eastward, Ch and on the attahoochee river,are less than 1 00 feet . In the w lo er part of this formation there are imppr tan t beds of clay, c u m in which purple olors are conspic ous . So e of thes e clays will one day come extens ively into u s e in the manufacture of m fire brick and various kinds of earthen ware . In the sa e for mation are f ound beds of yel low ochre,which have been mined in two or three localities . A fairly good qual ity of iron ore is N likewise found in many places in this formation . ext above T u s kal oos a m t 300 a the, co e abou feet of strata chiefly s ndy,to m a which the na e E u taw has been given . These beds, long the

Tombigbee and Alabama rivers, have yielded very few fossil

remains ,but going eastward,they become highly fossiliferous . Next above the E utaw follow the calcareous beds of the * r otten l imes ton e, 1 ,000 feet thick alon g the Tombigbee and

Alabama rivers,bu t becoming much thinner toward the east, h and giving out entirely before the Chatta ooc he is reached . This formation gives ris e to the calcareous soils of the black

belt,or canebr ake,. on e of the most noted farming regions in At a and m the State . the b se at the top of this for ation are two beds of phosph ati c gr een s an d,to which special attention will

be directed l ater . The uppermost divis ion of the Cretaceous has been nam ed R i of S pley. The strata are,in the western part the tate,cal car eou s below and sandy above ; toward the east this formation

* k e a A par t of this ro c k is a. true c hal f o rmation , rath r th n a limes tone . T h e o e a o h c h i th e name,rotten limes to ne,is open to many obj ec ti ns ,c h i f m ng w i s fac t l l that th e greater part of th e formatio n i s n ot a limes tone at a ,s tric tly s peak ing . A 27 GEOLO G Y OF A LA BA M . becomes much thicker,being feet on the Chattahoochee S m m river . In the eastern part of the tate the ost i portant strata of the Ripley are th e blu e micaceous marls which play s o prominent a part as a soil maker . M ater i al s of E con omi c I mp or tan ce i n the Cr etaceou s The most importan t materials in this formation are the ph os p hates . These occur as n odu l es of nearly pure phosphate of lime,similar to the phosphates of S outh Carolina,but which have nowhere been found in great abundan ce, or as ph osphati c g r een s an d,more or less calcareous,containing up to five per c ent . of phosphoric acid, occurring in large quantity . As above indicated,there are t wo horizons where these materials occur,namely,at the base and at the top of the rotten lime stone, and they outcrop across the S tate in two belts, on e immediately north and the other immediately south of the m black or prairie belt . In the Alaba a Geological Reports, and in occasional papers,much detail has been given concern ing these marls ; their capabilities have been fully shown by n experimen ts in several localities . It will, however,be a lo g time before they come into general use,as a mountain of preju m m M dice and conservatis will have to be first re oved . aterials of exactly similar quality have for many years been used with the best r esults in New Jersey . A part from these marls and phosphates , the Cretaceous has little to show of valuable mate rials, except the clays and ochres in the T u s kal oos a series ar m above alluded to . The clays e ined at several points along the Alabama Great S outhern Railroad in Jefi ers on and Tuska Y m m m loosa coun ties . ellow ochre fro this sa e for ation has been mined for a number of years in E l more county, near

Coosada station .

— s u b- T er tiar y. The divisions of the Tertiary have been

‘ of given fully in the table at the head the present article . A few words of explanation may be added

At the base of the Tertiary is found an impure limestone, thin and inconspicuous in west Alabama,but thickening east on C 200 ward until, the hattahoochee river,it is fully feet .

This we have called the Cl ayton l i m es ton e,formerly known d a r ou m on m as our y g p,fro a locality the Alaba a river .

Next above the Clayton ,we find on the Tombigbee river,a s eries of black clays, 1 00 feet in thicknes s,well expos 28 F' A A GEOLOG Y O L B A MA .

Black Bluff , on the S u c ar n oc hee r i ver , and,th r efore,called by w d m n the latter name . These clays thin do n rapi ly , beco i g more calcareous toward the east,and in Wilcox county fof m f m W w the base o so e fine prairies . Beyond ilcox county ,to ard

‘

f et . the east,this section o the Tertiary has not y been identified ' Next succeedin g the S u carn och ee,or Black Bluff group,is ’ th e fil ath ews L andi n g , or N ah eol a s er i es , Composed of gray san ds and clays ,with a highly fossiliferous bed at its base,an d On the m b a thick bed of lign ite at the top. To big ee river this E it group is nearly two hundred feet in thickness . astward, decreases in thickness,and is lacking en tirely on the Chatta

T he u N an al i a s er i es h ooch ee river . next gro p,called the af , maintains a tolerably uniform thickness across the State from d m the Tombigbee to the Chattahoochee . The be s are ostly sandy,but contain a great number of shells of a small oyster

e N ma called g r yph oea thir s a . ear the Alaba river,and eastward, the upper part of this group contains a gray aluminous rock , which very closely resembles th e buhrstone below described, ” - and,from this resemblance,called by us pseudo buhrstone . — er i m f Th e T u s c ah om a. This s es consists ainly o gray and yellow laminated, cross - bedded sands an d sandy clays,gener ’ ally poor in fossils, except at Y ellow Bluff and Bell s L anding, m m on the Alabama river. It aintains a pretty unifor thickness across the State of about 1 40 feet . — of T he B as hi . The characteristic feature this group in western A labama is a bed of green sand marl ,highly fos s il if ’ erou s , having its greatest development at Wood s Bluff,on the mm m Tombigbee river . I ediately below this arl we find several E f S e u l ah beds of lign ite . ast o the p g river,according to Mr . "

L angdon , the lignite is wanting . The thickness of this g roup varies,it being on the Tombigbee about eighty feet,and on Pea river 1 50 feet,while on the Chattahoochee river it is only forty four feet,and nearly devoid of fossils . — m m of T he H atch etig bee. This e ber consists brown , purple and gray laminated,sandy clays,and cross - bedded sands,about

1 75 feet thick,on the Tombigbee river, where a great abnu d E ance and variety of fossils are met with . astward ,th ese beds thin down ,and on the Chattahoochee river the thickness is n ot more than ten feet,but the lithological features remain practi cally constant . OF A A BA A 29 GEOLO G Y L M .

— I n m Th e B i t/tr 8 t0 7te. the western part of the S tate the ost prominent rocks of this series are aluminous sandstones ,or siliceous clay stones ,varying slightly in composition,and poor f A m f in ossils . In eastern laba a the percentage o clay decreases and the rocks become more calcareous ,an d the fossil s more abundant, and in place of the s il icified casts characterizing them on the Tombigbee and Alabama rivers, are extensive of m beds of shells, which oysters for a very large proportion . On the Tombigbee the thickness of this series is estimated at

400 feet, and this thickness decreases until, on the Ch attahoo chee river, it is less th an 200 feet . — T h e Cl aibor n e The thickn ess of this group On the Ala bama river is about 1 45 feet, and at Claiborne Bluff several m distinct strata have been described . The ost important of these occurs at the top, and is a bed of sand seventeen feet in

‘ thickness , filled with th e beautifully preserved shells which m have made this locality fa ous . Below this comes a series of beds,in which an oyster called os tr ea s el l cef or mi s is the most abundant an d characteristic fossil . Below these ostrea sellae formis beds we find another highly fossiliferous stratum, ex A m L L posed along the laba a river at isbon anding . The most persisten t member of this series is that which 1 s characterized by ostrea s el l aetormis ,and this is the only representative of the

Claiborne formation on the Chattahoochee river, where the

- thickness is only seventy fi ve feet .

- T h e Whi te L im es ton e. This is the uppermost member of m the E ocene in Alabama . The ost abundant and characteristic rock is a white,friable limestone " i cks bu r g l imes ton e) wh ich when freshly quarried can easily be cut with a saw or axe,and is used extensively,in the region of its occurrence,in the con n d T h struction of chimney a pillars for houses . ech ar ac teris

m r bi tic fossil of the white li estone is the o toi ol es lyel l i . The thickness of th e formation in Western Alabama is about 200 feet,which thickness it maintains across the S tate,being at l east 27 5 feet on the Ch attahoochee . The lower part of this series is made of an impure,clayey limestone (Jacks on ) ,which , in disintegrating, gives rise to black ,calcareous soils, similar to those of the black bel t of the Cretaceous but the topogra phy in these Tertiary prairies is extremely broken,and the n m region of their occurre ce is usually known as the li e hills . 30 L A GE O OGY OF L A BA M A .

— w Th e Gr an d Gu l f . S outh ard of the region of the occur

rence of the white limestone we have recently found,in Wash

in gton Mobile, Baldwin, and E scambia counties, sandstones

' an d cl ays of variegated color,which are characteristic of the

. i Grand Gulf formation of D r . Hilgard It is always exceed ngly diffi cult to discriminate between th e disintegrated portions of the rocks of this formatio n and th e surfa ce beds of drifted

materials wh ich over lie th at whole region , and. for this reason the presence in A labama of the Gran d Gulf beds has not until

lately been deffin itel y ascertained . Thes e beds belong, most

probably,to the Miocene division of the Tertiary,but th e ah

sence of well - defin ed fossils prevents our arriving at certainty n o this point . m m T h e Pas cagou l a F or mation . A ong the aterials brought up by an artesian boring in Mobile recen tly are some shells that have been recognized as characteristic of the Mio m n o m cene horizon . Inas uch as arine shells have as yet been

found in the Grand Gulf beds,it seems best to give a distinct

n m to M - m a e this obile shell bearing stratu . A fossiliferous stratum with the same shells as those from the Mobile boring h L . . as lately been discovered by Mr . C Johnson,of the U nited

States geological su rvey,on th e Pascagoul a river,in Missis mm sippi . This bed lies i ediately over strata of undoubted

Grand Gulf characters,and it may be a marine phase of the

Grand Gulf,but withal so entirely different from th e other d m f be s of this for ation as to be worthy o a name of its own ,

J u P s and Mr . ohnson has s ggested a cag ou l a,from the original

locality . n Mr . Johnso ,has also recently traced the Miocene fos s il if er ou s of m u f on C h deposits Alu Bl f, the hatta oochee river, in F lorida,westward an d n orthward to within a few miles of the C southern boundary of ovington county . It seems altogether probable that this phase of the Miocene will be found to extend into Alabama,an d. it may turn out to be identical with our Pascagoula, as above defined . The deep beds of sa nd which overlie this whole southern country stand in the way of geological examination , and t h e only chance of fin ding exposures of th e Tertiary beds which underlie these sands is l u fl'fs in the b and banks of the creeks . The recently dis cov ered phosph ates of F lorida are all associated with Miocen e

32 OF A A BA A GEOL O G Y L M .

The formation has recently been further studied by Mr .

McGee, from the Mississippi to the Potomac, and named by h im Appom attox,but recently an older name of D r . Hilgard has on e of ou r m im been adopted, namely " L afayette. It is ost portant formations , inasmuch as it makes the basis of the f g reater part of the soils of the lower p art O the S tate . These sediments ,like the all u vials,have no necessary connection with the rocks upon which they are now found, though in many cases to some extent modified by them,and their distribution is such as to precl ude the idea th s t they have been transported

n r m r In d \ and deposited by a y st ea at p esent e xisting . eed,r nan y / of the ph en emen a,seem to be explicable only on the supposition that they are carried along by rapid c u rrents of water,flowing fro m the n orth to the south, and s preading over t h e entir e width of the S tate from the east to the west ; more than this, the same deposits in th e adj oining S tates show that this great

flood was not confined to narro w limits, bu t extended over the f whole width of the Gul and Atlantic S tates . The thick n ess of these beds in A labama will perhaps average about fifteen or twenty feet,bu t we often find the older valleys excavated in the Cretaceous and Tertiary strata,which have been s u bs e quentl y filled in with these beds of pebbles an d sands to a depth

- of fifty or seventy five feet . The pebbles occur commonly near th e base of th e formation,and above them come the sands and the red loam,which latter usually forms the s u rface, except m where re oved by denudation . The beds of th is age are usu a m of m ally spread, as antle co paratively uniform thickness,

‘ over hill and dale of the older formations . In this way the red l oam of the L afayette group h as come to be the sub - stratum of th e m best far ing lands of the southern half of the State,an d its excellence is enhanced by the admirable under - drainage ff th e b a orded by peb les upon which it so aften rests . This formation occupies in Alabama perhaps five times the super ficial h l m area of any ot er sing e for ation . This formation until recently has been considered as a member of the Pleistocene,and the characters of its materials and the pecu liar distribution of the formation , s o utterly unlike those of the oth er Tertiaries, might well be considered a r s favoring this interp etation of the age ; but,on the other M m hand,Messrs . cGee, Cha berlin and S alisbury have traced 33 G A A BA A . I EOLOG Y OF L M

some yellow gravel,wh ich they consider L afayette, ben eath .

Certain deposits,which they make the lowest of the Pl ei s to

of L t it - m cene . If this yellow gravel is afayet e age, see s r P e necessary to assign it to the later Tertiary o liocene . Ther seems to be reas on f or h Opin g that foss il remains will yet be i foun d in the L afayette that will fix definitel y ts geological ag e.

A T E A RY FO RM T O N QU N A I S .

th e r " O th P Pl ei s toc ene. In tabula iew f e leistocene formations of A labama,and in the des cription which follows, the arrangement must n ot be understood to be chronological, for it is certain that,to some degree at least,these formation s

were contemporaneous , and they very plainly grade into each mu difi er en t ot her . Being accu lated under conditions, they.

are rarely to be seen togeth er, s o that their precise strati

‘ graph ical relations are n ot easily made out . In two instances I think I have s een the g ray Ozark sands overlying the second bottom loams,bu t in neither case could I be perfectly certain of the identifications . — R i ver T er r ace or S ec on d B ottom D ep os i ts The l ivers and other larger streams of A labama, especiall y those traversing the region over wh i cli the mantle of pebbles and sand above

described h as been spread,flow alon g val leys of varying width (often four to eight miles) cut down in to the rocks of th e i i country (Cretaceous and Tert ary) . The mmediate channel s of these streams, always more tortuous than the valleys above

mentioned,are excavated ou t of materials which have in th e past been depos ited by the stream itself,or ,at l east,by the cu r rents which once occupied the valleys between wh oes widely separated borders the present streams pursue their winding

courses,touchin g these borders,n ow on the on e side,now on

s ec on d bottom de os i t h the other . These constitute the p s ,whic

' are always above overflow,and vary in thickness from sixty

feet upwards,in the central part Of the S tate, to less than ten m feet,near the gulf . In co position they are uniform, and n o one familiar with our l ower rivers can fail to have noticed 34 OF A BA A GEOL OG Y LA M . t he comparatively low bluff s which form the banks on at least h m m one side of t e river . The second botto s for a nearly level terrace, sometimes a mile or two in width, slightly above the m high water ark of the rivers on which they occur . The first bottoms or flood plains,annuall y overfio wed, form a narrow t m f errace on one or both sides of the strea . o cou rse lower

“ than the main mass of the second bottom depos its out of h e n w ich they have b en excavated . The materials of the seco d " bottom are sand and clay in varying proportions ; these pre s ent usually very indistinct marks oi stratification,especially

' in the upper parts, wh ich are commonly s tifi er and more clayey than the lower and are u niversally used in the manu

I n of th e facture of brick. many places we find near the base terrace deposits a clay filled with fragme n ts of twigs and other vegetable remains,and in this clay are the roots of the stumps m n entioned below . As above stated,the immediate chan el of the stream is cut into this material,and the lower beds being m m uch ore sandy than the upper,there is a constant under m ining and caving Off going on on the outer side of the bends . i As this cav ng prog resses, stumps and logs are f i equ en tl y brought to view which have been bu ried under these deposits .

These are commonly s upposed to be cyp ress stumps,and are u in h m us ally a fair state of preservation . All the other p eno ena of the second bottom deposits go to show that they were connected with the n ow existing systems of drainage, but were formed when the general level of the waters was higher than at present,or before the streams had cut their channels

to . m the present depths The second botto s. are less local in c haracter and less closely connected with existing streams than th e first bottoms ; but, on the other hand, much more restricted and closely related to these streams than are the m h L various aterials constituting t e afayette series . Ou r second bottom deposits are probably nearly equivalent in time to the Port Hudson and overlying beds of the Mississippi river, but the material Of the latter is quite diff erent from that of our rivers,the diff erence being probably due in th e main to the fact that the Mississippi river reaches u p into the region once occupied by glaciers . The Port H u dson deposits m are built u p mainly of the aterials of glacial origin . The only o rganic remains which the second bottoms are known to A A B A M A 35 GEOL OG Y OF L .

m c ontain are th e cypress s tumps above mentioned . S o e of th e most productive soils of Alabama are formed of these second bottom materials and most of the celebrated river plantation s of former times rest upon these deposits . — Ozark S an ds While the terrace deposits j ust mentioned are confined to the immediate vicinity Of the rivers an d larger water courses, and are rarel y elevated more th an fifty feet above these waters, we find,especially in the southern part of the S tate, a mantle of gray sands ,with pebbles at the base, overspreading the country between the water courses up to 5 altitudes as high as 1 0 to 200 feet above sea level . These sands correspond to th e i nterflu vial phase of the Columbia Mc Gee m th e o formation of Mr . ,as the second botto s are repr s entative of the fluvial phase . The Ozark sands usually lie unconformably upon the red

loam of the L afayette formation , with a sharp and distinct

line of demarkation between th e two,and,wh ile scarcely ever more than four or five feet in thickness and holding very little

gravel upon the divides ,they increase in thickness and in the percentage of pebbles along the slopes leading down to the minor streams,ofteii forming sandy terraces on e- fou rth of a A a d mile in width alon g the creeks . s bove state ,the strat ig r aphic al relations of these sands to the second bottom

deposits are not easily made out, since they rarely occupy the same areas,yet they often form a sort of third or higher

terrace along some of the larger rivers ,a few feet above the m n d second botto s a quite as wide . ‘ — ’ —“ B il oai J oas t S an ds This includes the immediate gulf coast and islands of Mobile and Baldwin counties and an exten u of M m sion p the bay obile to an undefined li it . The name

should not be understood as implying sterility,f or much of the ” h e of he t t m . M region is choice truck far ers r . L . C . Johnson, wh o has recently given this part of the S tate some study,de scribes the coast sands as consisting essentially of thin alter

' and an d nating layers of sand s y clay . The formation is quite variable becau se,in the course of its str u c ture,old beaches and marshes ,both salt and fresh,were worked in with the regular strata, and now,when exposed along the shore,appear as a t m O h t m . t Mr . patch‘ of black bot o often studded wi ld s u ps J ohnson thinks that these deposits on our coast are the result 36 ~ ‘ GEOL OG Y OF A L A B A MA . of three principal agencies , viz " the tides of the gulf, the

Mississippi river,and the united rivers that pour into Mobile m f m bay . The ti e o their accu ulation was probably, in part at least , contemporaneous with the formation of the second bottom dep osits,but,inasmuch as the same agencies are active at the present time that have been for a ges, thes e c oast sands grade into the recent shore deposits . Mr . Johnson has

‘ recently shown h ow the waters of the Mississippi in 1 890, breaking throu gh the levee at the Nita plantation , poured through Ponchartrain and other lakes into Mississippi sound, carrying its sediments to the very mouth of Mobile bay . Naturally the contributions of the Mississippi river are more pronounced as we g o westward,and at Biloxi a boring for an artesian well has given a good section showing the alternations of coarse sand with marsh mu d down to a depth of eighty feet .

Mr . Johnson has proposed the name B i l oxi as a substitute for coast sands . — “ Recent U nder this head are included all soils , first m n bottom deposits,sand bars,etc .,now in progress Of for atio ” or attribu table to causes now in operation . — — A l l u vi al F l ood Pl ai n D epos i ts S wamp an d F i r s t B ot — Of tom L an ds . The current a river is rarely so sluggish as to allow the complete deposition of the finer matters held in suspension in i ts waters,bu t gently flowing streams con s tan tl y leave on their banks, where the retardation of th e cu rr ent by friction is greatest, a mixture of fine sand and W th clayey matter . hen , however, e waters rise above the banks and spread over the flood plains, the matter held in in — suspension will be dep osited parallel zones the pebbles , sands and coarser meterial on the immediate bank of th e stream,where th e current is swiftest,and the fine sand and clay further back in the swamp,where the comparative still ness of th e water permits the complete settling of all th e matter held i n suspension . The soils of the river swamps, thus accu mulated,are of extraordinary fertility,but have the t serious drawback tha they are liable to periodical overflow .

These deposi ts are being made at the present time,and they, ' ther efore,represent the most recent geological formations and form the natural transition to the soils ,which will be discuss ed in another article .