Foundation of Exact Geologic Correlation

View metadata, citation and similar papers at core.ac.uk brought to you by CORE

provided by University of Northern Iowa

Proceedings of the Iowa Academy of Science

Volume 22 Annual Issue Article 32

1915

Foundation of Exact Geologic Correlation

Charles Keyes

Recommended Citation Keyes, Charles (1915) "Foundation of Exact Geologic Correlation," Proceedings of the Iowa Academy of Science, 22(1), 249-267. Available at: https://scholarworks.uni.edu/pias/vol22/iss1/32

This Research is brought to you for free and open access by the Iowa Academy of Science at UNI ScholarWorks. It has been accepted for inclusion in Proceedings of the Iowa Academy of Science by an authorized editor of UNI ScholarWorks. For more information, please contact [email protected]. ~..,.-=.c:-___:;o'.::...------~ -- -

Keyes: Foundation of Exact Geologic Correlation GEOLOGIC CORRELATION. 249

FOUNDATION OF EXACT GEOLOGIC CORRELATION.

CHARLES KEYES. In the last generation or two there appears to have been little advancement made along lines of general geologic correla tion. Two controlling reasons stand out prominently. On ac count of the fact that the criterion of fossils is so largely mis used and is so generally unchecked by other critical criteria it is continually losing much of its former precedence. The adop tion of the lithologic formation as the cartographic unit is also almost a complete failure for the reason that no account is taken of the change,· replacement and effacement of its essential characters from place to place. All this confusion gives rise to an interminable synonymy which even a specialist in a circum scribed region cannot always satisfactorily make out without de tailed review of the original sections on the ground. When the mania for proposing new tit.res for geologic forma I I &.: tions becomes. so acute as it has in the case of the collector of ( fossils there is little real h.ope of simplifying stratigraphy so ! that the average. worker going into a district may. easily un derstand, aNd· without undue expenditure Of time and effort, acquire fundamental insight into the problems presented. In the last quarter, of a century there appears to be not a single systematic effort on the part of the geological surveys of the country to accomplish what should have been done years and years ago. Instead matters in this respect are growing rapidly worse instead of better. In no field of science is there presented so chaotic a state of nomenclature as that relating to stratig raphy. l In casting about for tlie proper area for which to construct a suitable generalized section of local rocks the quadrangle as r ordinarily selected appears to be much too small to be of any real ' service. The county is likewise too limited in extent. In size the state seems most satisfactory for trial-tests: in continental correlations. A comprehensive section of the Iowa rocks was given last year in the Proceedings of the Academy. This year a similarly constructed section of the Missouri rocks is annexed for comparison. Later, sections of Kansas, Oklahoma, Western

Published by UNI ScholarWorks, 1915 1 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32 250 IOWA ACADEMY OF SCIENCE GEOLO~

Texas, New Mexico and Arizona will be presented, as parts of a ' south . can be suggested fc broad but exact scheme of general correlation. known only from the ~ecc As fundamental elements in the upbuilding of the North Of the Ozarkian series. American continent the areas of Iowa and Missouri present some very nearly the exact eqm exceptionally instructive contrasts. In the geological sections · th The Roubidoux sa of these two. states the record of each physical event is accentu nor . mond sandstone of the s ated and paralleled with those of others. probably represents so:ne Several notable features first deserve enumeration. In the The Gunter sands~one .is. one area certain phases of unconformity are repre8ented by tre In the Ordovicic divi1 mendous sections of sediments. At one time a great and. lofty represented by the yell mountain range stretched across the northern area, while in the found in• the north. Eai south remained a lowland plain. In its present aspect the Ozark sented in Iowa by depoi dome did not exist until very recent times. These circumstances which have no sediment have an important bearing upon the proper interpretation of the developed in the sout~. regional stratigraphy. The Tennessean seri~s For many years the two sections have appeared to be so un .re aches in southern. Mis . like that little exact comparison was possible. This apparent attains great diversity ll discrepancy arises from several causes. First, there is small distribution it exten~s attempt to assign to the several geologic formations recognized the Mississippian series their proper taxonomic ranks. Second, different· names for the therefore, really belong same terranes are used in the two states. Third, state lines pre the sedimentation of .w vent workers in the one province from extending their investi The importance of t~1s gations into adjoining districts and thus making exact strati The Arkailsan series . graphic correlations. Fourth, terranes are represented in one by a marked hiatus. T state which have no exact depositional equivalent in another. strata in such a mannE Fifth, change in lithologic character of formations tend to con if not one of co:mple1 fuse the delimitation of formations. Ozark dome in souther'. The similarities of the two sections are as important as are great Arkansan foni;! sandstones. This atta11 their differences. The former are the more app.arent since the ness of more than 15 taxonomic values of the several formations, the usage of the equivalent of the ~nc~ same nomenclature, and the positions of the terranes in the time the coal meas:iires m t scale are made to harmonize in a way never before attempted. bonic successioD; !1l?P, To the detailed differences a,ttention is specifically called in an any marked divisim to assign a taxo1 other place. ~ose visions eguivalen~ to Of the larger differences between the two sections the most cedure is not behevei notable may he briefly enumerated. First of these are those and it is difficult. to which relate to the Cambric rocks. The Croixan series, which vance over our prior in Iowa is scarcely exposed above stream-level, is well differen Another notable c tiated in Missouri and· widely outcrops around the Ozark dome. general sections is tl rine Tertiaric beds; Although the successions in the two states have nearly the same nental deposits of thi thickness no equivalents of the subdivisions recognized in the sections with the gre

https://scholarworks.uni.edu/pias/vol22/iss1/32 2 !~ .

Keyes: Foundation of Exact Geologic Correlation )!ENCE

GEOLOGIC CORRELATION 251 pr~sented, as parts of a Iat10n. south can be suggested for Iowa, where the rocks are mainly of the North buil~ing known only from the records of deep-well sections. i M1ssouri present some Of the Ozarkian series the Jefferson dolomite appear8 to be th: geological sections . very nearly the exact equivalent of the Shakopee dolomite o:f the ysrnal event is accentu- north. The Roubidoux sandstone corresponds to the New Rich mond sandstone of the same region. The Gasconade dolomite enumeration. In the probably represents somewhat more than the Oneota dolomite. ~re represented by tre- The Gunter sandstone is a local deposit. 1me a great and. lofty r In the Ordovicic division the Early part of the sequence, iern area, .wnile in the represented by the Yellville dolomite, does not appear fo be isent aspect the Ozark found in•the north. Early Siluric sedimentation is not repre : Thes!l circumstances sented in Iowa by deposits. Early and Mid Devonic terranes, ~ interpretation of the which. have no sedimentative representatives in Iowa, are well developed in the south. . ppeared to be so un The Tennessean series, which is so poorly developed in Iowa, ~i~le. This apparent reaches in southern Missomi a quite remarkable thickness and li'1rst, there is small attains great diversity in lithologic character. In its geographic ~rmations recognized . distribution it extends far southeastward into Alabama; while :erent. names for th the Mississippian series extends southwestward. The· two- series h" e Ird, state lines pre- therefore, really belong fo quite distinct geographic provinces, mding their investi the sedimentatio-n of which overlaps somewhat along one edge. naking exact strati The impo-rtance o-f this distinction is not generally recognized. represented in one The Arkansan. series in both Missouri and Iowa is represented tivalent in another by a marked hiatus. The plane of unconformity bevels all older lations tend to con~ strata in such a manner as to indicate a long period of erosion, if not o-ne of complete planation. On the south side of the s important as are Ozark dome in southern Missouri appears the feather..edge of the apparent since the great Arkansan formation comprisjng coal-bearing shales and sandstones. This attains in central Arkansas an enormous thick ' ·the usage of the ness of more than 15,000 feet. This series is the depositional irranes in the time equivalent of the unconformity which characterizes the base of . before attempted. the coal measures in both Missouri and Iowa. The entire Car lcally called in an- bonic succession appears so important terranally and has so many marked division lines that Chamberlin and Salisbury pro pose to assign a taxonomic to each of its two principal di sections the most rank visions equivalent to that of .Devonic or Cambric. This p.ro f these are those cedure is not believed to have sound stratigraphic :foundation; ixan series, which and it is difficult to see how the proposal is any distinct ad I, is well differen- vance o-ver our prior conceptions.

! the Ozark dome. Another notable difference between the Missouri and Iowa ~ nearly the same general sections is the presence in the first named state of ma rine Tertiaric beds; and in the last mentioned state of conti ·ecognized in the nental deposits of the same age. The correlation of both of these sections with the great "Southwest standard section is also given.

Published by UNI ScholarWorks, 1915 3 ~ l Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32 1 .l• GE~ 252 IOWA ACADEMY OF SCIENCE

GENERAL GEOLOGIC SECTION OF· MISSOURI. PERIODS ISUB-F

PERIODS SUB-P. SERIES ERAs I TERRAN ES THICK ROCKS --- LATE_ LATE---· 25 Loess ------Interval I ------Unconformity Wisconsin 25 Gravels rQUATERNARIC Mm _____ Pleistocene _____ --- Peoria ------25 Loess DEVONIC------Mm __ _ 0... Interval ----- Unconformity <:) N Kansas ------50 Till Q ---- z EARLY-.- Interval •[;il ----":'" Unconformity --- E ARLl 0 LATE ___ . l'oinsettan _____ Lafayette ------50 Gravels Mm_____ Interval --- --.,.-- Unconformity TERTIARIC ______Wilcox 100 Shales EARLY __ Crowleyan _____ Porter ------50 Clays II L ATE. I Inte,rval ------··---- Unconformity LATE ____ Egypt ------Ripleyan-----~------150 Sands SlLURIC------M ID-- 0 ... CRETACIC______Interval ----- Unconformity <:) Mm _____ ---- N Dakotan ______Nishnabotna 20 Sandstones E <:) ------EARLY __ Comanchan____ Interval ~ ----- Unconformity "' --- L ATE l!! JURASSIC------Interval . ------Wanting TRIASSIC------Interval ----- Wanting I LATE ____ Unrep'sented ------Atchison ----- 300 Shales MID-. Forbes 35 Limestones Platte 125 Shales ORDOVICIC------Plattsmo~tb:-· 50 Limestones Lawrence ---- 250 Shales Missoitrian _____ ParkvilleStanton ______30 Limestones -:;-- 100 Shales - Mm _____ Iola 40 Limestones EARL Thayer ------100 Shales Bethany ------75 Limestones Marais· des C. 30•0 Shales · Des Moines ____ Henrietta ____ 7 5 ILimestones Cherokee ---- · 225 Shales 0 LATE ... Arkansan______<:) Sonora ------100 /Shales N CARBONIC______Q Chester 100 Shales i;.i Kaskaskia 125 Limestones .. 'l'ennessean____ Aux Vases ___ 150 Sandstones Genevieve 150 Limestones ~ st. Louis _____ 200 Limestones CAMBRIC------' Interval ·' ----- Unconformity MID- Spergen ---- EJARLY __ ----- 100 Limestones lflississippian__ Warsaw ----- 65 Shales Keokuk ------75 Limestones Burlington ------125 Limestones Interval ----- Unconformity EARl Chouteau ---- - 80 Limestones PRO SUPERIORIC_____ EARJ Waverlyan ____ Hannibal ---- 75 Shales TER- Louisiana ___ 50 Limestones ozo - Saverton - SEJLKIRKIC ______.. 50 Shales .... IC Grassy ---==== 40 I Shales

https://scholarworks.uni.edu/pias/vol22/iss1/32 4 Keyes: Foundation of Exact Geologic Correlation

GEOLOGIC CORRELATION 253 ~CIENCE

[ON OF· MISSOURI. PERIODS SERIES ROCKS ERAS\ ISUB-P. J TERRANES ·I THICK I Interval ----- Unconformity TERRANES THICK RoCKS LATE ____ Ohernungan ____ Snyder ------125 Shales 25 Loess l';enecan ______. Callaway ---- 50 Limestones terval ----- Unconformity Interval ----- Unconformity __3_0_! Shales . isconsin --- 25 Gravels Wittenberg -- ~oria ------25 Loess DEVONIC------IMm_____ Erian ______Interval ----- Unconformity terval Unconformity Grand Tower 150 Limestones ~nsas ------50 Till ------1------0riskanian _____ Clear Creek-- 225 Limestones terval ----.,. Unconformity EARLY-- Interval ----- Unconformity 1fayette --- 50 Gravels ------Helderbergian. Bailey ------160 Limestones ~erval -- .... -- Unconformity --- Interval ----- Unconformity ilcox ------100 Shales --- irter 50 Clays LATE ____ G oweran ______Sexton ------50 Dolomites ------terval Unconformity Iriterval ----- Unconformity ··------wpt 150 Sands SlLURIC------Mm _____ Niagaran ______Bowling Gr. 40 Dolomites ------terval Unconformity Int!')rval ----- Unconformity ------'shnabotna 20 Sandstones EARLY __ Alexandrian ___ Noix 30 Limestones Girardeau __ 50 Limestones terval ----- Unconformity --- LATE ___ , Maq1wketan ___ , Bufallo ------60 Shales ~erval . _____ Wanting 75 Sandstones ----- 1 Thebes ------teival ----- Wanting ~ Int~rval ----- Unconformity Grep' sented --- McCune ------50 Limestones chison ----- 300 Shales Mm _____ Mohawkian ____ Interval ----- Unconformity 1rbes ------35 Limestones ---- atte 125 Shales ORDOVICIC______Bryant 150 Limestones attsmouth 50 Limestones .Joachim ----- 150 Dolomites Lwrence ____ 250 Shales --- I --- an ton 30 Limestones Minnesotaii_ ___ ; St. Peter____ _ 125 j Sandstones 1rkville -i-- 100 Shales ----~-1------la 40 Limestones EARLY-- Ir,terval ------,Unconformity 1ayer 100 Shales ------Limestones Ca.nadian ______Yellville Dolomites lthany ------75 ----150 trais des C. 30~ Shales Interval Unconformity mrietta ____ 75 Limestones ---- 1erokee ---- 225 Shales .JE.fferson ___ _ 200 Dolomites --- LATE ____ O,i·arkian ______Roubidoux - 150 Sandstones nora ------100 Shales Gasconade i-- 250 Dolomites --- Gunter ------100 s andstonoo Lester 100 Shales Lskaskia 125 Limestones Interval ____ _ Unconformity IX Vases ___ 150 Sandstones mevieve 150 Limestones Proctor ----- 60 Dolomites Louis _____ 200 Limestones Eminence --- 200 Dolomites CAMBRIC------Potosi ------ 300 Dolomites terval Unconformity Doe Run ----- 60 Dolomites ----- MID----- Croi(f;an ______Derby ------40 Dolomites 1ergen ----- 100 Limestones Davis ------ 150 Shales arsaw ----- 65 Shales Lesueur ----· 250 Dolomites lOkuk 75 Limestones Frederickt'n 200 Limestones 1rlington Sandstones ------125 r~imestones I,aMotte 250 ~erval ------Unconformity EARLY-- Interval ----- Unconformity Louteau ---- 80 Limestones PRO- SUPERIORIC____ , EARLY-- Anirnikian _____ , Ironton. ------200 Slates mnibal ---- 75 Shales TER- Pilot Knob __ _ 50 Conglomerates misiana --- 50 I,imestones OZO- ,verton ---- 50 8hales IC SELKIRKIC______Interval ----- Unconformity :assy ------40 Shales

Published by UNI ScholarWorks, 1915 5 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32

254 IOWA ACADEMY OF SCIENCE GEOL

ROCKS ERAS PERIODS I STJB-P.1 SERIES TERRANES I THICK I ARCH Skrainka Diabases ALGOMIC---·----- LATE---· Franooisian ____ Iron Mount'n 300 Porphyries EO- 500 Granites ZOIC Knob Lick------SEQUENCE OF RC -AZO- Not exposed-. IC ERAS PERIODS SUB-P. --- LATE..---, ---·

QUATERNARIC•. MID-----· J ...0 0 N 0 Ii!: Iii ---· 0 EARLY--. - - LATE ____ l - TERTIARIC------· ---- MID---·--· 1 ------EARLY--. - LATE ____ ] ---- ' . I , (

Mm______-

...0 ICRETACW------L 0 N 0 ---- 1ll Iii l!l EARLY __./C I_

JURASSIC------LATm ____ IJ16 . .I TRIASSIC______EARLY __.I~ I

https://scholarworks.uni.edu/pias/vol22/iss1/32 6 Keyes: Foundation of Exact Geologic Correlation GEOLOGIC CORRELATION 255 ~NCE

RANES I THICK I. ROCKS ll:a ____ \Diabases l{ount'n 300. PorpJ:iyries Lick--- 500 Gramtes SEQUENCE OF ROCK FORMATIONS IN KANSAS. --s:posed-. . ERAS PERIODS SUB-P, SERIJilS TERRANES THICK ROCKS

25 Alluvium LATE---- Recent ______.1------Interval Unconformity Wisconsin -- 100 Loess Kingsdown __ 150 Adobes Pearlette --- 25 Volcanic ash Meade -----··- 40 Gravels QUATERN ARIC-- MID-----· Pleistocene _____ Interval. ----- Unconformity Kansas ----- .6Q Tills Afton ,,.------25 Clays Inter\ial ----- Unconformity EARLY--. 10 Clays Interval ------Unconformity Blanco ------100 Sands LATE---- Tea:homan ______! Goodnight --- 150 Clays TERTIARIC------· Interval ----- Unconformity MID---·--· Loupian ______Ogalalla ---- 300 Sands Clays Arikaree ------500 EARLY--. Not exposed Interval ----- Unconformity LATE---- Montanan ______1------Plerre ------400 Shales Niobrara ___ _ 300 Chalks 1 Hays ------·· 50 Limestones Victoria ----- 150 Shales 100 Shales , Coloradan ______g~~~~1orii"-::: 100 Ldmestones Graneros ---- 150 Shales 50 Shales ICRETACIC------· MID-----· ~~;%1fc;!"me __ _ 150 Sandstones Dakotan ______Pete ------50 Shales \ Interval ----·· Unconformity --- Mentor ----- 100 Sandstones I Interval ------Unoonformity EARLY .•. Comanchan ____ Kiowa ------·· 150 Shales Cheyenne ___ _ 60 Sandstones . I Interval ----- Unconformity 1------1---- \ IChaquaqua __ 75 Shales JURASSIC------LATE---- Morrisonian ___ . Travester ------50 Shales Unconformity a------____I . Interval ------\ !Trujillo ------75 Shales TRIASSIC------EARLY .•. Dockuman _____ Tecovas. ------50 Shales . I Interval ----- Unconformity

Published by UNI ScholarWorks, 1915 7 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32

25;6 IOWA ACADEMY OF SCIENCE GEOJ GENERAL GEOLOGIC ERAS PERIODS SUB-P. SERIES TERRANES THICK ROCKS

I Quarter ERAS PERIODS Stra-P. master ---- 300 Sandstones 1Greer 100 Gypsums ·1Woodward __ 300 ~nales LATE---· LATE---- Oirnarronian___ Blaine ------ 75 Gypsums M":m ____ _ Enid ------100 Shales ---- QUATERNARIC Interval ____ _ Unconformity --- EARLY-- 'Vellington __ 200 Shales Marion ----- 150 Shales .. Winfield --··-- 100 Shales Oklahornan ____ . Riley ------60 Limestones LATE---· Matfield ----- 75 Shales Wreford ,____ _ 50 Limestones Neosho 125 Shales Cottonwood _ 10 Limestones ---- MID ____ _ Atchison -- 500 I shales CARBONIC-~--L-. Forbes ----- 30 Limestones I Mm ______Platte 200 Shales Plattsmouth 50 Limestone~ Missourian _____ Lawrence __ _ 300 Shales TERTIARIC------Stanton ----- 125 Limestones Parkville ___ _ 100 Shales Iola ______30 Limestones Thayer ----- 100 Shales Bethany ----·· 225 Limestones EARLY--. Marais de C.- 400 Shales Des Moines ___ Henrietta __ _ 100 Limestones Cherokee ___ _ 300 Shales Arkansan______Interval ----- Unconformity --- Tennessean ___ -1 Unrep:eiiented EARLY ___ llfississippian __ Keokuk ------75 Limestones Burlington __ 100 Limestones

EXPLANATORY NOTE. LATE ___ _

The carbonic section of Kansas soon comes in for detailed discussion in an other connection. There are several cogent reasons for not adopting here the subdivisions suggested. by the Kansas geologists. As the divisional lines fol lowed well show they are not materially different from Broadhead's arbitrarily chosen and "convenient" groups of half a century ago. CRETACIC------That Kansas geologists should not agree among themselves upon what forma Mm____ _ tions their several subdivisions should include, that tliose in neighboring states should not agree among themselves or with the Kansas workers, and that none of these should agree with the Federal representatives and others who have vis ited the region is not passing strange because none of the expressed opinions take into account genetic bases. Until the laws of priority in names, the canons

of nomenclature, the basic principles of stratigraphy, and the essential in EARLY __ fluences of regional diastrophic movements are recognized. -confusion and dis agreement must continue to prevail in the simplest matters.

https://scholarworks.uni.edu/pias/vol22/iss1/32 8 Keyes: Foundation of Exact Geologic Correlation DIENCE GEOLOGIC CORRELATION 25-7 GENERAL GEOLOGICAL SECTION OF NEW MEXICO. ~RRANES THICK ROCKS

PERIODS SUB-P. SERIES TERRAN ES THICK ROCKS uter- ERAS aaster ---- 300 Sandstones ~er 100 Gypsums --- . _..,______LATE---. Jarnadan ______.. 25 Abode ,odward -- 300 ~nales ~ine 75 Gypsums Palomasan ____ ------100 Shales MID----- . ------200 •.rm ld ------QUATERNARIC --- erval Unoonformity ------.------250 Gravels ------EARLY-- Gilan______1llington -- 200 Shales Interval ---- Unconformity ,rion ------150 Shales -- --- nfield --··-- 100 Shales Llano Limestones LATE---. Peoosia'li-"----- Estacado __ 300 Sands ey ~----"--- 60 :tfield ----- 75 Shales ---- ·eford ,_____ 50 Limestones Interval ----- Unconformity osho 125 Shales --- ttonwood 10 Limestones MID ______Sante Fe 50.0 Clays - Arriban______~ Galesteo -----· 800 Sands I ~hi son ------SOO-lshales • rbes 30 Limestones Interval Unconformity ------Shales ---- ~tte 200 0 ------fttsmouth 5_0 Limestones ... Chaco 1000 Clays Shales TERTIARIC______Canyon wrence --- 300 Ohaman______tnton ----- 125 Limestones =IOI Largo ----- 700 Sandstones rkville ---- 100 Shales = a ------30 Limestones fl: Interval ----- Unconformity ayer ------100 Shales I;,) 225 Limestones Torrejon ...... 300 Marls thany ----·· ---- "" EARLY--- Lrais de C._ 400 Shales Interval ----- Unconformity inrietta --- 100 Limestones Naoim-ientan ______.. ---- erokee ------300 Shales Puerco 500 Clays Unconformity -· ____ ..; ---- terval ------Interval Unconformity· Unrepresented Archuleta _...;_ 250 Conglomerate ---- i Aztecan.:': ______1okuk 75 Limestones .. Interval --- Unconformity 1rl!ngton -- 100 Limestones .. - MaJ1:well 800 Shales Ratonan ______Houten -----··---- 600 Sandstones . ·-·. ~ -. Maya 100 Conglomerate ,·l, ------! ------Unconformity --- Interval --··-· Navajo 1000 Shales Pictured -----· ::>TE. Larainian______Cliffs 150 Sandstones ---·------LATE ____ Unconformit.Y Interval ------Lewis 600 Shales in for detailed discussion in an- Chacra------200 Sandstones Montanan ______Mesa Verde __ 800 Shales 1asons for not adopting here the• Pina Vltitos_ 250 Sandstones its. As the divisional lines fol Interval ----- Unconformity ent from Broadhead's arbitrarily ..0 ------try ago. c CRETACIC------La Jara ----- 1000 Shales IOI Coloradan______Apishapa ---- 500 Shales !Ilg themselves upon what forma ~ Timpas 300 Limestones :§) MID _____ ------' that those in neighboring states r;u Galllnas ----- 200 Shales .;!!! Kansas workers, and that none of Glorietta ...... 300 Sandstones Dakotan______------:atives .and others who have vis- Interval ----- Unqonrormity 1 none of the expressed opinions --- Kiowa ------100 Shales Conglomerate ; of priority in names, the canons Garrett ------50 ------atigraphy, and the essential in EARLY ___ _Oomanohaii_ ___ Interval ----- Unconformity re recognized confusion and dis ------Washita 500 Limestones plest matters. Fredericks- burg ------200 Limestones 17

Published by UNI ScholarWorks, 1915 9 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32

258 IOWA ACADEMY OF SCIENCE GEOLI

ERAS j PERIODS I SuB-P.1 SERIES TERRANES I' THICK I ROCKS PERIODS LATE---· Intervfl,l ---- Unconformity ------1------'--~ LATE ___ ~ 11 Chaquaqua -·· 150· Shales Travester --·· 100 Shales !-----Mm___ ._,ll .TURASSIC------· Mm_____ M orrisonia'ft___ Exter ------7 5 Sandstones ORD!)VICIC-~--~- --- ~ Unconformity Interval ------EARLY .. ]J EARLY-- Zunian______McElmo 300 Shales La Plata ------300 Sandstones LATE~--· l Wingate ----- 900 Sandst

Capitan ------2500 Limestones (J Gua;daloupan_. Eddy ------10()0 Sandstones 1------ANIANIC ______, Ir.terval ---- Unconformity --1------Torrance ---- 500 Shales F Yeso ------600 Shales Bernalillan____ Manzano --- 500 1------Sandstones Interval ---· ---- 'Unconformity Tellera ------300 Limestones CARBONIC______M aderan______, Gallegos ----- l.00 Sandstones Antonito ---- 200 Limestones Mm_____ . ------1------Mosca ------200 Limestones Lunasan ______Coyote 75 Sandstones Montosa ---- 400 Limestones ,lZO Sandia ------250 Shales IC Interval ------'Unconformity I,adronesian•.. Alamito ------200 Shales 7'ennessean ____ Interval ------Unconformity Modoc 2010 Limestones NOMENCLA~ Mississippian •. Sierra ------50 Limestones . EllARLY--. I,ake Valley_ 150 Limestones Grande ------25 Limestones Abo Sandstones, Lee. (Bul Waverlyan _____ Interval --- Unconformity Term exact synonym of Man Berenda 50 Limestones LATE---· Martinian ______1------rick. Interval --- Unconformity DEVONIC______---·1------1----- Alamito Shales, Keyes. ( J 01 Mm_____ Perchan ______Bella ------· 250 Shales Probably representative of soi Silver ------200 Shales EARLY •• Interval ---- Unconformity Mississippi valley. LATE ___ _ ------·1------Wanting Albuquerquan Series. The --- SILURIC------· MID-----· Santa Ritan___ Naiad ------· 250 Limestones some quartzites, exposed to t Cibola ------· .---175 Limestones Tijeras canyon, east of Albm EARLY •• Interval ----- Unconformltv

https://scholarworks.uni.edu/pias/vol22/iss1/32 10 Keyes: Foundation of Exact Geologic Correlation

GEOLOGIC CORRELATION 259

ROCKS ~RR~Es \' TiiicK \ PER.IC)DS I Sm!"~· I SERIES I· TERRANES ITHICK I ROCKS rval ____ .. Unconformity --- LATE ____ iltlimbresian, ___ , Cristobal ___ _ 165 Limestones --quaqua _., 15~ Shales vester ...... 100 Shales MID---"-· Montoyan ______Frondosa ___ _ 100 Limestones er ------75 Sandstones ORDQVICIC______1----1~---~-1------Armendaris • 300 Limestones >rval - Unconformity EARLY __ El Pasan _____ J,-----~ --- Interval . ----- Unconformity ~Imo 300 Shaies Plata --- .300 Sandstones LATE~--· Uhiricahuan ___ Lone ------300 Quartzites 1gate ...... - 900 Sandstones Uh~or,idian _____ Carrasco ___ _ 75 Limestones 800 Shales 1 Roux ---- Conglomerate ~arump -- 600 CAMBRIC------. . Burro ------. 500 Quartzites Mm_____ Dragoonan ____ , Hawkins ___ _ 50 Limestones ;rva._l "'I----.. - Unconformity Mangas ------. 100 Quartzites 1jillo ...... -----300 Shales EARLY__ Interval ----- Unconformity pvas 200 Shales ------• Fo.lencian ____ • Graphic ----- 1,0.010 Lavas erval - Unconformity SUPERIORIC____ · Sandoval ___ _ Granites I ---- a.rt er- •:. Interval ~---- Unconformity ~aster ...... 150 Shales ~er 125 Shales· Albuquerquan. Ysidro ------ 1500 Shales ------·· 425 Shales ~fijeras ~----- 250 Quartzites ~ves ------l:'ELKIRKIC_c__ ·__ 'erval . ----·· - Unconformity Interval Unconformity ('}arnuan ______Antonio pitan ------2500 Limestones ··2000 Slates dy ------10'()0 Sandstones ANIANIC------· Interval Unconformity terval -- Unconformity ------1------Truchas 9(10 'Slates rrance - 500 Shales Pecurisan ______Penasco ----- 400 Quartzites BO ...... ---- 600 Shales Serna ------"- 1500 Schists fnzano 500 Sandstones --- Interval Unconformity Lerval - - Unconformity ------Solitario 800 . Slates Hera 300 Limestones H.ociada ---- 250 Limestones ,negos ----- 100 Sandstones Tao11an------"" Sapello ----- 300, Quartzites 1tonito ------200 Limestones Ninos ------10010 Schists osca 200 Limestones Interval ____ _ Unconformity 1yote ------75 Sandstones ontosa ----- 400 Limestones ..iZO Slates india 250 Shales IC Gneisses ------Schists terval -- "C'nconformity - Shales lamito ------200 1terval ------Unconformity odoc ------2010 Limestones NOMENCLATURE AND SYNONYMY. erra ------50 Limestones ake Valley_ 150 Limestones rande ------25 Limestones Abo Sandstones, Lee. (Bull. U. S. Geol. Surv., No. 389, p.. 12, 1909.) Unconformity 1terval ------Term exact synonym of Manzano sandstones as defined by C. L. Her erenda ----- 50 Limestones rick. Unconformity ~terval ---- - Alamito Shales, Keyes. (Journal of Geology, Vol. XIV, p. 154, 1906.) le Ila 250 Shales Probably representative of some part of the Arkansan coal series of the ------200 Shales Liver ------·Mississippi valley. µterval ----- Unconformity --- Wanting Albuquerquan Series. The great sequence of argillaceous beds., with --- some quartzites, exposed to the extent of more than 2,000 feet in the falad ------250 Limestones :ibola ------175 Limestones Tijeras canyon, east of Albuquerque. nterval ------Unconformitv

Published by UNI ScholarWorks, 1915 11 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32

260 IOWA ACADEMY OF SC[ENCE GEOl

Antonio Slates. Thick, somewhat metamorphosed, argillaceous beds Chaco CZays, Keyes. (l which lie beneath the Tijeras quartzite, and are well displayed at the 1908.) Main body of cla~ north end of the Manzano mountains. They are underlain by other but the W a~atch sequence of th as yet undetermined sediments .. Chiacra Sandstcines. Mas An.tonito Limestones. Lowermost of the heavy· gray limestones ex member of the Mesa Verde 1 posed in fine; sections at the southern extremity of the Sandia range. relief feature in th,e southea Apish:ipa Shales, Gilbert. (Sev:enteenth Ann. Rept., U. S. Geol.·Surv'., Chaquaqita Shales. Sectil Pt. ii, p. 567, 1896.) . fh:~ely exposed in the Chaqli Archuleta. Shales. The title. is here proposed for .that of Ammas . Formation of the San Juan region, ·Which is p.:reoccupied. Chaman, .Seri¢sr Keye~. 1908.) Main body of, so-·ca At·mendaris Limestone~. Main body of the Early Ordovicic lime trict stones well displayed in the Sierra de los Caballos. · Arriban Series, Keyes. (Proc. Iowa Acad. Sci., Vol. XIII, p. 226, · Chaves Shales. . Lowef!U~ 1908.) Essentially the entire Miocene section as represented around the great Capitan limestones fo. southern end of the Rocky Mountains. Chiricakuan SQri(3s. L~t~ Aztecan Series. A thick,. pust-Laramian succession of Cretacic sedi veloped ,in the Chirieah;ua a ments in the San Juan region. · Chloridian Series ... · Mid ( Bella Shales, Keyes. (Trans. American Inst. Mining Eng., Vol. posed in Grant cQunty; a,n XXXIX, p. 147, 1909.) Abrigo sequence of limesto:i;i: Berenaa Limestones,. Keyes. (Trans. American Inst. Mining Eng., Oibo'la Limestones. Impj Vol. XXXIX, p. 147, 1909.) Late. Devonic section of the Mimbres cropping at the· Cibola mill region, whlch possibly repl'esents the attenuated eastward extension of· Cimarronlian Series, Cragl the thick Martinian limestones of eastern Arizona. 18, 1896.) ' BernaliUan Series, Keyes. (Rept. Governor New Mexico to Secretary Colomdan Series, Endlicl of Interior, for 1903, p. 341, 1904.) Term originally proposed for the Ninth .Ann. :Il,ept., p. 126, .~ Mid Carbonic red-beds below the Cimarronian series. . Com,anchan Series, Hill. Bliss Quartzites, Richardson. (Bull. Texas Univ. Min. Surv. No. 9, i887.) 1904.) Basal member of the Mid Cambric .section of the Franklin Coyote. Sandstones, Herri~ mountains; and the sole representative of the Dragoonan series of that Vol. II, fascicle 3, p. 4, 190 area. .. Cristobal Limestones. M~ Burro Qiiartzites. Main body of the Mid Cambric quartzites which tion in the Franklin, Cabam immediately overlie the Ohloridian series of limestones near Silver City. I Dakotan Series, Meek arn Canyon Largo Sandstones, Newberry. ·(Macomh's Exp.ed. Green deJphia, Vol. XIII, p. 410, 1 River, Geol. Rept. p. 1, 1876.) Dragoonan Series, Dumbl Capitan Limestones, Richardson. (Bull. Texas Univ. Min. Surv., No. Vol. XXXI, p.. 1902.) Mi 9, 1904.) vicinity of Silver City. Ori Carrasco Limest01'/,es. Main calcareous member of Late· Ordovicic southeastern Arizona. age well displayed back of the Carrasco smelter property near Silver Dockuman Series, Hill. Oity. 189, 1890.) Cenocene Series. Latest formed deposits 9f the Quaterriaric age. Dolo"Y'esan Series, Cross.

https://scholarworks.uni.edu/pias/vol22/iss1/32 12 Keyes: Foundation of Exact Geologic Correlation i[ENCE GEOLOGIC CORRELATION 26i

1orphosed, argillaceous beds Chaco Giays, Keyes~ (Proc. Iowa Acad~ Sci., Vol. XIII, p.. 225, ii are well displayed at the 1908.) Main body of clays., shales and sands heretofore referred to are underlain by other but the Was.atch sequence of the San Juan basin.. · '·" ~ · .:.· ·· · ;: ·rr " .. Ckacr'a Sandstones. Massive sandstone layers forming. the· upper heavy· gray limestones ex member· of the Mesa Verde coal formation and constituting a prominent :tity of the Sandia range. relief feature iii th,e southeastern part of the San Juan.,~ion. ,nn. Rept., U. S. Ge<>l.-Surv., · Ohaquaqua Shales. Section of alternating red sandstones and shales, finely exposed in the Chaquaqua canyon, i:O. northeast' New Mexico. oposed for .that of Animas , p.reoccupied. ChwwurLSeri~s, Keyes. (Proc. Iowa Acad. Sci, Vol. XIIJ, ,p. 224, the Early Ordovicic lime 1908.) Main body of, so~called Wllsatch section, in the San Juan dis trict~ abaUos. ··Chaves Shales .. . Lowermost se.ction of red which rest. on the iad. Sci., Vol. XIII, p; 226, . ·, . . . . ' ' . . . ·. . sh~les,,- . . '-.. m as represented around the great Capitan limestones i:Q. tlte G,uadaloupe mountains .. Chiricahuan /3(}ri(3s. 'Late Cambric limestone suceessioJ:), well de-

, succession of Cretacic sedi- veloped ju the Chiricah.ua and CaballQS ranges. . . , 1 , - • • ' L ,. -' ,. • • ~ ~, - '• ~ • ' · Chloridian Series.· Mid Cambric limestone succession extensively ex- i Inst. Mining Eng., Vol. posed in Grant county; a,nd probably t:P,e eastern a.ttenuat1Qn of the Abrigo sequence of limestoi:;tes of Bisbee, .merican Inst. Mining Eng., Cibola Umestones. Important Mid Siluric limestone member cmt mic section of the Mimbres cropping at the Cibola mill at Silver City. mated eastward extension of Cimarron~an Series, Cragin. (Colorado College Studies, Vol. VI, p, Arizona. 18, 1896.) aor New Mexico to Secretary Coloradan Series, 'Endiich~ (U. S. Geol. and G~og. Surv. Terr., i originally proposed for the Ninth Ann. Rept., p. 126, 1877.) . l" mian series. Comanchan Series, Hill. (Am. J~ur. Sci.. (3), V~i 'XXXJII, p. 298, exas Univ. Min. Surv. No. 9, i887.) section of the Franklin ~ric . Coyote. Sandstones, Herrick. (Bull. Hadley Lab. Univ. New Mexico, the Dragoonan series of that Vol. II, fascicle 3, p. 4, 1900.) . Cristobal Limestones. .Mai!l l;lody of Late Ordovicic limestone sec [id Cambric quartzites which tion in the Franklin, Caballos, Fra Cristobal and Mimbres ranges. ,f limestones near Silver City. Dalw·tan Series, Meek and .Hayden. (Proc. Acad. Nat. Sci. Phila ·(Macomh's Exp.ed. Green delphia, Vol. XIII, p. 410, 1862.) Dragoonan Series, Dumble. (Trans, American Inst. Mining Eng., . Texas Univ. Min. Surv., No. Vol. XXXI, p .. 1902.) Mid Cambric section finely exposed· in the vicinity of Silver City. Originally defined in the. :brag

Published by UNI ScholarWorks, 1915 13 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32

262 IOWA ACADEMY OF SCIENCE GEOL

Eddy, Sandstones, Keyei;i. (J0111:nal 9f Geology, Vol, XIV, .p; 154, Guadaloupan Series, Girt; 1906~)-.. T)le term Delaware· propos~d by G. .B,. Richardson for this 1902.) ' formation is preoccupied. . · Hawkins Lim'estones. In · El/Pooan Series; Keyes"' (Science., Vol. xXIII,-.p. 922, 19Q6.) Term age which are intercalated i: is, restricted to the Early: Ordovicic section of the Franklin, Caballos Grant county. and Mimbres ranges .. ·. Houten Sandstovnes. · Mid . Epice·ne Series, Keyes. (Proc.. Iowa Acad. Sci., Vol.. XXI, p .. 186, northeastern· New Mexico . • l91~.} ,:Early, orpre~Glacial, section of .the Quaternaric succ~~on. J ornadan Series. Prine .Exter Sandstones, ~.;ee'. (Joumal of ~eology, Vol. X, p. 45, 1902.) deposits. : Fr~dericksbwrg :Umestones, white.· (Proc.· .A.cad, 'Nat.. ·sci., Phila Kelly Limestones, Herric1 delphia, 1887, p. 40, 1887.) Part cif Cretacic ~ection well exposed in th.e 310, 1904.) Synonymous wi Sierra, de los Muleros. wj:l&t. of El Paso...... · . Kiowa Shales, Cragin. ( Frondosa Limestones. Main body of Mid Ordovicic"series in Frank- 1894.) Main body of ComB lin mountains, which carries a Gafona-Ti:enton farina. · · . · New Mexico and southweste1 F'!issetmann Limestones, Richardson. (Am. Jour. Sci. (4), Vol. 'XXV, Ladronesan Series, Keyes. p. 4 7~' 1908.) Includes the entire Siluric· se~tion o.f the Franklin moun- 1906.) Remnant of coal-be tains. , .... , ) '"' . . . . _ , _ with the Arkansan series of <. · Galisfoo.Sandsto?1'e'S; Hayden. · (U. S. Geol. and Geog. Surv::. Terr.t La Jara Shales. Thick, UJ Third Ann. Rept., p. 167, 1873.}'' , , dan series around the southe · .· GaUegos Sandstooes. Thick sandstone beds in. the middle. of the Lake Valley Limestones, 1 lVIaderan limestones in the .Sandia· range. Secretary of Interior, for 19~ . Galli~ Sh.ales. · Basal, member of the C9loradan series, well developed bonic section exposed typicl on Gallina Creek, near Las Vegas. Mim bres region. _.

https://scholarworks.uni.edu/pias/vol22/iss1/32 14 I ----=------

Keyes: Foundation of Exact Geologic Correlation

II ENCE GEOLOGIC' CORRELATION }eology, VoL XIV, .p; 15~, Guadaloupan Series, Girty. (A'Ifi. Jour. Sci. (4), Vol. XIV, p. 363, G. _.B, . Richardson for this 1902.) ' ,. Hawkins LimestiJnes. Important calcareous beds of Mid ·Cambric ' ~xni,. p. 922, 1906. )- Term age which are intercalated in the basal section o! quartzite$ exposed in !l of the -Franklin, Caballos Grant county. . Houten Sandstones. Middle sandy portion of the Raton series in ;ad. Sci., VoL .. XXI, p. 186, northeastern· New· Mexico. e Quaternaric suc~~ion. · · Jornadan Series. Principal intermont plains soils and surface i1ogy, VoL X, p. _45~ 1902:) deposits. ~oc .. Acad, Nat. Sci., Phila Kelly Limestones, Herrick. (American Geologist, Vol. XXXIII, p. lc ~ection. well exposed in the 310, 1904.) Synonymous ·with Lake Valley limestones. Kiowa Shales, Cragin. (Colorado College Studies, Vol. ·V, p~ 49, 1d: Ordovicic ·8eries in Frank- o.ton raima. ; ;. . 1894.) Main body of Comanchan shi;iles well exposed in northeastern New Mexico and south~estern Kansas. · · m. Jour. Sci. (4), Vol. XXV, Ladronesan Series, Keyes. (Journal of Geology, Vol. XIV:, p. 154; ~ection o.f the Franklin moun- ... 1906.) Remnant of coal-bearing formation which is to be correlated with the .Arkansan series of the MissiSs:ipp.i valley. ~~~l. a~d· Geog. Surv: Terr.t La Jara Shales. Thick, uppermost black shales section of the Colora. dan series around the southern end of the Rocky mountains. beds in the middle. of the Lake Valley Limestones, Keyes. (Rept. Governor· of Nt.iw Mexico to Secretary of Interior, for 1903, p. 341, 1904.) ·Main body of Early Car >lo:radan series, well d_eveloped bonic section exposed typically at Lake Valley and elsewhere in the Mim bres region. wh,ich lies . below the ~quence La; Plata Sandstones, Cross and Sp.encer. (U. S. Geol. Surv., Folio ote canyons at the _north ,end 60, p. 3, 1889.) 1ediments underlie it: . Laramian Series, White. {Bull. U. S. Geol.· and Geog. Surv. Terr,, of the Early Cretacic section Vol. III, p. 625; 1877.) ~stern Kansas. . . . Le Roux Shales, Ward, (Am. Jour. Sci. (4), Vol. XII, p. 401, 1901.} n widely developed in the Gila Lewis Shales, Cross and Spencer. (U. S. Geol. Surv., Folio 60, p. 4, 1899.) ;he Dakotan ~eries around the Llano Estacada S(J;n.ds, Hill. (Bull. Geol. Soc. America, Vol. III, p. 87, 1892.) Mainly the Pliocene deposits of eastern New Mexico and American Inst. Mining Eng., western Texas. is best shown at Lake Val~ey; Lone Quartzite. · Late Cambric section of alternating quartzites and mtative of the Choute.au hme- metamorphosed ·limestones well displayed in Lone mountain, near Sil ver City. uence superposed on pre-Cam- Lnnasan Series. Main limestone sequence in the Manzano·. moun. tains. r and Irrig. Pap., U. S. G:ol. /Jfaderan Series, Keyes. (Rept. Governor of New Mexico to Secretary extension of the Cimarroman of Interior, for 1903, p. 341, 1904.) · Uppermost gray limestone sequence Lclow the red-beds in the ·sandia. mountains.

Published by UNI ScholarWorks, 1915 15 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32 GEO IOWA ACADEMY OFSCIEN(i)E N-acimientan Series, Key Magda.Zena Grc. Colorado Sci. Soc., Vol. III, p. S., Ge_ol. ~ur;y,,r N-0,d®r p, 93, 1888.) ·-· ' R-Qci

Published by UNI ScholarWorks, 1915 17 Proceedings of the Iowa Academy of Science, Vol. 22 [1915], No. 1, Art. 32

IOWA ACADEMY OF SCIENCE 'GEO

Sandoval Granites.· Red granites penetrating all pre~Cambric rocks Truckas Slates. The up] of the Sandia, Magdalena and other ranges. · .. :.· . at Picuris, north of Santa . Santa Fe Clays, Hayden. (U. S. Geol. Surv. Terr., Prelim~ ·Field · Travester Skales. Varieg ·Rep.t., p.,66, . .1869.). sandstones well displayed Santa. Ritan Series. Mid Siluric section as repesented around ·Fort Mexico. '.Bayard, and in the .Caballos and Franklin ranges; it carries the Niagaran Trujillo Shales, Gould. fauna. Surv., No. 191, p. 26, 1907: · Sapello · Quartzites . . Main body of Archeozoic quartZites below the Valencian Series. Late1 thick limestone. section in the. Solitario · peak region, northwest- of Las granites. · . Vegas.. · Vermejo Skales, Knowl1 · Serna Schists. Basal part of the Archeozoic section near Picuris, 527, 1913. Probably exruJ north of Santa Fe, on the west flank of the Rocky mountains. Washita· Limestones, Sh1 Shandon Qitartzites, Gordon.: (Prof. Pap. U. S. Geol. Surv., No. 68, p. 583, 1857.) . p. 225, 1910.) • Basal quartzites in the Caballos mountains, probably Wingate Sandstones, D11 bEifonging to the Dragoonan series. p. 136, 1885-.) ' Shinarump CmgZom.era'tes, Powell. (U. S. Geog. and Geol. Surv., Yeso: Shales, Lee. (Bu Geol. Uinta Mts., p. 41, 1876.) Tetm restricted to middle Sierra Limestones,·Keyes. (Trans. :American Inst. MiningEng., Vol. y sidro Skales. The thi XXXIX, p. 149, 1909.) Uppermost member of Early Carbonic se ments lying above the g~ . quence. at Lake Valley... sharp, truncated arch irJ Silver Shales, Keyes. (Traris. American Inst. Mining Eng., Vol. Manzano ranges. XXXIX, p. 147, 1909;) Mid Devonic black shales, weathering brown zunian Series, Dutt<>n. or red, of the :Mimbres region .. 1885.) SoUtario Slates. Extensive -section of tilted Archeozoic beds lying above the main limestone exposed. in Solitario ·mountain, northwest ·of Las V..egas. Taosan Series. T11ted Archeozoic sediments exposed in Solitario ·peak. They strike N. 50 degrees W., · across Taos county, and· dip about 60 degrees SW. · · · Tec01Jas Shales, Gould. {Water Supply and Irrig. Pap., U. S. · GeoL Surv., No. 191, p .. 231, 1907.) Tellara lA'mestones; '])hick; uppermost gray limestone member· of the Maderan series exposed on the east flank. of the S1;1ndia .range. · Tijeras (juarleites. Thick quartzitic beds best ex:p.osed in the great Tijeras arch of pre-Cambric rocks at the south end of the Sandia range. Timpas IAmestones, Gilbert. (Seventeenth Ann. Rept., U. S. Geol. Surv., Pt. ii, p. 566, 1896.) · · · 'L'ortance Shales. Upper, or verniillion section of the, Bernalillan series of C'arbonic red-beds in the Manzano mountains. · . . · To-rtijon Clays, Dall; (Eighteenth Ann. Rept. ·u. S. Geol. Surv., Pt. ii, p. 347, 1898.)

https://scholarworks.uni.edu/pias/vol22/iss1/32 18 Keyes: Foundation of Exact Geologic Correlation

DI ENCE 'GEOLOGIC CORRELATION

~ating all pre~Cambric rocks Truchas Slates. The upper slate section of the Archeozoic .succession at Picuris, north of Santa Fe. . Surv. Terr., . Prelim; ·Field Travester Shales. Variegated beds,lying immediately above the Exter sandstones well displayed in Travester canyon in northeastern New as repesented around ·Fort Mexico.. . nges; it carries the Niagaran Trojillo Shales, Gould. (Water Supply and Irrig. Pap., U. S. Geol. Surv., No. 191, p. 26, 1907.) · · . Leozoic quartzites below the Valencian Series. Latest pre-Cambric succe8Sion of volcallics: and ~k region, northwest· of Las granites. Vermejo Shales, Knowlton. (Am. Jour. Sci., (4), Vol. _XXXV, p. Bozoic section near .. Picuris, 527 1913. Probably exact equivalent of Mesa Verde shalea. Rocky mountains. Washita· Lim.eStones, Shumard. (Trans. St. Louis Acad. -Sci.; Vol. I, ). U. S. Geol. Surv., No. 68, p. 583, 1857.) ltballos mountains, probably Wingate Sandstones, Dutton, (Sixth Ann. Rept. U. S. ·GeoL Surv., p. 136, 1885.) • S. Geog. and Geol. Surv., Yeso: Shales, Lee. (Bull. U; S. Geol. Surv., No. 389, p: 9, 1909.) Tetim restricted to middle section of Bernalillan series. ican Inst. Mining. Eng., Vol. Ysidro Shales. The thick argillaceous member of Proterozoic sedi tber of Early Carbonic se- ments lying above. the g1·eat quartzite, which· is best exposed in the sharp, truncated. arch in\ Tijeras canyon between the Sandia and n Inst. Mining Eng., V oL Manzano ranges. 1k shales, weath~ring brown Zunian Series, Dutt<>n. (Sixth Ann. Rept. U. S. Geol. Surv., p. 137~ 1885.) ilted Archeozoic beds lying lrio mountain,· northwest of

1ents exposed in Solitario Taos county, and dip about md Irrig. Pap., U. S. GeoL ay limestone member ·of the the ·Sandia range. 1· best exp.osed in' the great th. end of the Sandia range. ~h Ann~ Rept., u. s. ~leol.

section of the Bernalillan tnountains. · . Rept. U. S. Geol. Surv., Pt.

Published by UNI ScholarWorks, 1915 19