The Supai Group

S ubdivi sion and Nomencl a tu re

cKE By EDWIN D. M E

C O N T R I B U T I O N S T O S T R A T I G R A P H !

G E O L O G I C A L S U R V E ! B U L L E T I N 1 3 9 5

The S upai Forma tion of the Grand Canyon region is rais ed in rank to S upa i Group and div ided into four formations tha t range in age from E arly P ennsy lvanian to Early P ermian

D O OFF C W H O UNITE STATES G V ERNMENT P RINTING I E, AS INGT N UNITED STATES DEP ARTM ENT OF THE INTERIOR

B M S ecre ar ROGERS C. . ORTON , t y

GEOL OGICAL SURV E!

M l E . cK e e i V . v y , D rector

Lib rary of Congress Cataloging in Publication Dat a Mc Kee E d in Din iddie 1 9 0 6 , w w , — Th e S upai Group Sub divis ion and nome nclat ure . ( Contrib utions t o s tratigraphy) ( Ge ol ogical S urve y Bulle tin 1 3 9 5 -1 ) : Bibliography p . - . D . : I S up t of ocs no . J — — G 1 . Ge o t ti hic Pe mi n. 2 . Ge t ti hic Penns ni n. 3 . e logy , S ra grap r a ology , S ra grap ylva a ology , — — — Stratigrap hic Nome nclat ure A riz ona Grand Canyo n region. - 1 . . . : in 1 3 9 5 1 Titl e II S erie s . III . S eries Unite d S tate s Geological S urve y Bull e t — — . N 4 7 5 6 1 9 02 2 Q E 7 5 B9 o . 1 3 9 5 1 [ Q E 6 7 ]

For sa e b th e u e r n te n d e n t of ocum e n ts ov e r n m e n t r n t n ffice l y S p i D , U . S . G P i i g O

ashin ton 040 W g , D . C . 2 2

- - S to ck Number 024- 001 02656 2 CONTENTS

In troduction : field terminology and new nomencla ture Wa tahomigi Forma tion M anakacha Formation We scogame Forma tion E splanade Sands tone Correlation wi th previous subdivi sions Type section of Supai Group in Havasu Canyon References ci ted

ILLU STRATION

FIGU RE 1 . n x ma of su n n n t n n I de p Hava Ca yo , or her Arizo a

CONV ERSION OF MEAS U REME NTS TO METRIC EQU IV ALENTS

1 mile

CONTRIBU TIONS TO STRATIGRAP H!

THE S U P AI GROU P — S U BDIV ISION AND NOM ENCL ATU RE

M cKEE By EDWIN D.

ABSTRACT

The Supai Formation of the Grand Canyon region is raised in rank to Supai Group and nt s su s s n and t n n t s divided i o four formations . Wide pread rface of ero io hi co glomera e bed r separate these formations which range in age from Early Pennsylvanian to Ea ly Permian . st to un s t t n the Watahomi i Manakacha and Wesco ame From olde yo ge , hey are amed g , , g t ns and th s n n n t s t ns t s t ns are in Forma io e E pla ade Sa ds to e . The ype ec io of he e forma io su n n in he n Hava Ca yo t vici ity of Supai village .

INTRODU CTION : FIELD TERMINOLOG! AND NEW NOMENCLATU RE Probably the firs t geologis t to carefully consider subdivis ion of the

u o on n o o o n e un s was . . S pai F rmati i t l gical , readily rec g izabl it F E M f o f s o o u . In n o o atthe the U S . Ge logical S rvey maki g a t p graphic map B n u n in 1 90 - 3 no s of s the right A gel q adra gle 2 , he ticed that the red bed thi o on o o n H s f rmati , t gether with the verlyi g ermit Shale , characteri tically

o n o o n n s n s s on ou er ded i t three pr mi e t cliff , i ter per ed am g f r well o s n on f o o un s was devel ped slopes . The di crimi ati o these t p graphic it ’ called to my atten tion by Matthes in the 1 930 s in connection with my “ s u s of n ss on o us u t die the Supai Formatio . A field cla ificati that pr ved ef l in o rec rding data at that time and in all subsequent work resulted . u s on of u on s s of o o ss on us S bdivi i the S pai the ba i t p graphic expre i , ed u n s n - n s on o n o o n un s : d ri g the pre e t field i ve tigati , rec g ized the f ll wi g it un o n u s n un s n Upper cliff it, l cally i cl de a recedi g ledge it (E pla ade cliff) Upper s lope unit (divided by conglomerate into two parts) Middle cliff unit Middle s lope unit Lower cliff unit Lower s lope unit s un s can ou ou n n on and The e it be traced thr gh t the Gra d Ca y , they o one end to the o ou in n differ remarkably little fr m ther , alth gh , ge eral , J l J2 CONTRIBUTIONS To STRATIGRAP H!

un o ss and o n n o s and the cliff its are m re ma ive pr mi e t t ward the we t, the In n s n slope units are less conspicuous in that direction . ma y we ter sections the middle s lope unit is so weakly developed that the lower and i n s s to o . u o n t middle cliff u it eem merge t gether F rtherm re, the ex reme n n n on s on s in of o s o wes ter Gra d Ca y , lime t e bed the middle the l wer l pe unit are so massive and cliff forming that this unit locally is divisible into three subunits .

Although subdivisions of the Supai as originally delineated were based

n on o o and n on s of o s n e tirely t p graphy ( i directly the type r ck repre e ted), n s un ] on s and su s to o n certai key bed , fa a z e , marker rface came be rec g ized, nd n o to o M a they le t much supp rt correlations from place t place . os t important of the key beds are widespread conglomerates that occur at three horizons (in addition to the ba sal conglomerate on the Redwall on f Limes t e surface) and are recognized throughou t mos t o the region . s on o s o s to s o u 1 ou two- s the The e c gl merate , l we t highe t , cc r ( ) ab t third

s n u o s o un n s of un di ta ce p the l wer l pe it , (2) ear the ba e the middle cliff it, and 3 ou of u ( ) ab t the middle the pper s lope unit .

The key bed conglomerates are dis tinctive li thologically The upper two on o s sso su s of os on n c gl merate are a ciated with marked rface er i , havi g as u as 45 in nn s us s to s n i on relief m ch feet cha el ; th , they eem repre e t reg al un on o In so s of n s o s . on n u and c f rmitie me part the regi , mari e fa a ab ve below these conglomerates show that hiatuses of appreciable magnitude s n u w o in are repre e ted by them . The ppermos t conglomerate as rec gnized

25 of 3 1 s ons su one was o n in 1 9 of ecti that I mea red, the middle rec g ized 27 s ons and o one in 1 4 of 5 n ecti , the l wer 2 sectio s .

Partly on the ba sis of widespread eros ion surfaces and diagnos tic con glomerates as sociated with them and partly on the basis of topographic ss on s n u of n n on expre i that facilitate mappi g , the S pai s trata the Gra d Ca y are here divided into four formations which together are class ed as the u o 1 is s u . us u o on of on 1 9 0 S pai Gr p Th , the S pai F rmati Dart ( ) here rai ed in n to u ou and n ou o ons as o o s ra k S pai Gr p divided i to f r f rmati , f ll w o s to oun s : Wa tahomi i Manakacha and Wesco ame ( lde t y ge t) g , , g o ons and n n F rmati E spla ade Sa ds tone .

WATAHOMIGI FORMATION

The Watahomigi Formation i s named from Wa tahomigi Poin t on the wes t side of Havasu Canyon abou t PAmiles northwes t of Supai village and o f s n is as directly ab ve the type section o this formation (fig . The pelli g

1 6 . n on . 9 2 U S . o o u o u give the Ge l gical S rvey top graphic map , S pai , Ariz s n i s o n n a su n ns but Thi ame a c mmo family ame among the H va pai I dia ,

o H su M s o 1 and os or of the fficial ava pai ember hip R ll , 972, m t all the “ n ns of I dia this name use the spelling Watahomigie . 3 THE SUPAI GROUP— SUBDIV ISION AND NOMENCLATURE 1

— FIGU RE l . su n n n t n n s n u and nts on Hava Ca yo , or her Arizo a , howi g S pai village poi n n s the Watahomi i Manakacha and Wesco ame t ns ca yo wall from which g , , g Forma io derive their names and the eros ional bench ( shaded) for which the Esplanade Sand s t n i n t n Of t ns : Manakacha Wes m s . t s co a e o e amed Loca io ype ec io MWE , , g , and s n W h mi i W ata o . E pla ade; , g 1 4 ooN i 'Rmtn l ot“ 7 0 an RA' noM y nr

‘ ' l hr forma t i on c onsis ts large ly ol linir s t om and modal/nit; in a b out

' fi i a o onionoand in mos t auras lon ns a lt id slo " w i h i t ‘ ll 'fd l tt n l w p , , g y p , h c . t ' i e ’ t t ' ! t h i th i nfi tiv a s w ll im f t . mm n h om i m ol e n i l d a L b on C o o ly , o n u l nu u ut ! t r ne r it e n n tl m o ns c t mg o w : o on a o a s bas , a d a o : m o lo a lly a b ou

' - t w r t t c nct e m lr th ir t he t o hii ds h dist i op . Th idd d ol lot mo ion is t m tit t m t ime t ne n n vv « i n" ti n o p o d os ly ol l s o a d lo ns a nwwi Jill in W wo o s, dividing t he lon na tion into lowe r two wi ts an: lfl ‘llt‘ V ‘Ed

n l onnl v v v no ' t ht ' l n w n o t lil ’ e n vr o a id o o Mo o a ag ; upp r Va , ab u ‘ a r z t y r t : W t ‘ l lonu ww is noid n d o b At ol n in . h h mi i a b w g , o a mg l ata o g i o n t r w t ' t ' n v onlommhly on h Red all l l im wm and it onlon nahly o erl ain by me k n t n m a lw Forma io .

MANAKM JHA FORMATION

‘ ’ ' l ht ' m kaflha Poi nwt ion it twnusd h om Manal w ha Point on thr

‘ ‘ “ t e f i t w v t ' e no aid l l w n on m l ai ll . hi n o l ! oo h y , d y a bo Sup i ay l s w ll i g is ’ u t e if r e u it m nding o U p i . C y log nl Su v y may on nr mwy h may ol h ovel uadran e At nu n! thr ol li: ia l la t /mo nMr ml mhi Roll ” “ q gl , ; l o r p , W : W

" ' ‘ ‘ th e sp e ll ing Maria nna lot th e i ndian la mily oi tha t nanny l ht ' tyul ' w t ion oi t he Iom wt ion i alon th r wlw n i whinh e ins n t g Am a l , b g i l e thi c r t t r t e i vil ag and wind! up nnyomid o ward h p oin . Th Ma wl a olw

t r e t w' « t e t w m i nim oi h low s nui ooi Jill in h Sui/i i i Group and als o l onwll

' l nt l w t l we r a il t n t ' t ' t t c t w h oi slow a l o i ( o l l uni and n ddl slop uni ). i onsis s oi t i t m lr ’ dd ul l imy naturis t/i n" oi W i l tl)‘ lim mt onr wi th minor amoonnol ’ t ' t v t c l t e W t n t t ht ' mudo m . m h h m o l i o s o n o whly on a a o igi l on a i on, lr i ondni y in moot plai n ht ing indi wuid b y it t ha n” : h ow slow b e l ow to « lill a ll ow an d by tl w pn uwnu ' ol thr lowe rmost bandwnwa ol t he ‘ ’ nl ' l r ! l nd t t u l t Mnn w w . l h opp : r i o my ol l w lomw ion it! an on on on ni y

' nwi lu ' d by n out la w oi e ros ion and b y 2) Win d nonglonu wu' ol thr

' t e l ‘l ll t t u r n h m w w li uni li /l na ) , o

f t t t c' ”i Wait ol disi n oo u l ow linidt ran n hrou hout h Grand Can on . g gi g, g y ' ' “ l l u' omw: wi t ( olop v unit ) it “ithm Awloi n oi Ur i Moint ' tna n l l ) am; p “ t hi : l t e t l l t ‘ l w w r nu ' w t m . hm ound i n i w no l l q l l fl a l id ol i h ” .

Mit! V0 11 MA‘I ION

‘ - ' i ' ‘ ’ l he Wi w i gmm l onnnt ion is na me d li om Wt w w i tu l oint on t hr W ‘ 0! w i n ol l lnw a n n a ut m l” t wr t t w C yo , b o 5 i ; w o h l ol Sumovilla mand

‘ dnm t l a llow l l h i n w w t r a ! y wi nn i Ca yon, do n hit h h pr wn m

( l l twln i n " t t t t ' f ' U t xm ) ho , ni il o h vlllny Immin A goo d M N) " ol lw loi t i ml l t i l l lb “r n e d a lon t hi " l t t r t n d i v : r i s g s a l, bu h ry o wi n it on /hm h ‘ ' tw il t lu t r i t 1 “ ‘ " l " hn i nor h . l h W / 44mm l t flfl tl jflfil ,d onmwn l y oi min o r

‘ 4 nm lwdd ad nd to ni ' i wi nd linu' t r w m nf t l l w o o y oo n hit h lon nw wo l n lll , ‘ but i t nu lwlfl os h oot lo ll ‘lu' b lt l lfl ‘ tumm sl opc oi ntmlmwul hit up) ”

’ lt t ' v uu e e i v v b l jfl it no n w wn l in th t yp o n t i on but it w t/ n! manl y v i y

' wlu n 4 law l l ‘ ( - t t t l i mnd i n ; on. Modmo m i t w o n bu no no ' ‘ THE sc p s r OE OL P — nmrz wrsmrs A ND m uem n r ru 15

i the Supa G roup .

1 s . 87 21 in erri n to t s en c is ca ve d in the u e rm o t p , ) ref g hi b ch , whi h r pp ’ n i ow s nd s to be s O the u a n his dm t io n O the Tom ea are a . Sub a e d f S p i , p f p sequen t references to the Esplanade pla tform were made by Davis o nso 1 1 1 . o on n 1 1 . a t 9 1 9 1 4 . 8 1 3 922 R bi ( , p N ble ( , p . 2 . 7 : . p D r

. w o h nd 1925 and Ot s . n tual the n as e t t e sa ( , p her Eve ly , ame appli d ' “ s ton a o s the b n h : for con en n O r ferenoe the ro u o f e th t f rm e c v ie ce f e . g p hard sa nd s tones which suppo rts and for ms this shelf is termed the

‘ ' ” te 1 29 . ton M O u o m on . 9 E splanade Sands e [ ember f S pa i F r ati ] (Whi . p “ l l and th e u 0 e O u a r -red sa ndstones are ) pper 27 fe t f the S p i , ha d , dark "

no n o s the s n sa n s on S to anow 1986 . k w l cally a E pla ade d t e ( y , . p The formation consis ts pri marily Of very fine grained cr os s -s tratified n t o unts o f s ts to ne sandsto e that form s mas sive cliffs . I incl udes small am il and u s on th e h n o s o s b n s or c s ses and in m d t e at w at er i t l pe . e che , re e .

s rn r n n on on a ns so ns b d s o f s u . ear we te G a d Ca y , c t i me exte ive e gyp m N r n of n Can o n it G a d Wash Cliffs in the extreme wes tern part the Gra d y .

' apparently interfingers with the Pakoo n Lime s tone o f Mt ' Nair ( 195 1 ) un o s fo r t s o a o n is der Shivwits Plateau . The type sec ti n elected hi f rm ti

on ss s o the nn an o n of Ha as u al g the Apache trail , where it pa e fr m i er C y v rrnit S a e to th e broad E splanade platform bench occupied by the l l e h l . e It is unde r a n The Esplanade Sands tone is Of Wo lfcampian ag . l i s n an e unconforrnably by the Wescogame Formation of La te Pe nn ylva i ag . The boundary is marked by a well -developed s urface of ero sion wi th so me - channels more than 40 feet deep and by a pe rs is te nt lime sto ne pe bble con o na d is o e a n b the Her t Sha e of gl mera te . The Es pla e v rl i y mi l Leonardian age and separated from it in ma ny plate s by a greatly n n chan eled surfa ce of eros io . J4 CONTRIBUTIONS TO STRATIGRAPH!

The formation consis ts largely of limes tone and muds tone in about

u o o ons and in os s o s s o s eq al pr p rti , m t area , f rm a ledgy l pe , which retreat f ss Re ll n on o o dwa s o . o ne fr m the rim the ma ive Lime t e C mm ly , o on o o u s or n its s and no o u s o ou c gl merate cc r at ear ba e , a ther cc r l cally ab t - f o n i two thirds the di s tance up . The middle third o the f rmatio s o os os of s on and o s ss in so es ons c mp ed m tly lime t e f rm a ma ive cliff m ecti , n n n o o two s dividi g the formatio i t three parts . The l wer part are believed on un n to of M orrowan u r o con fa al evide ce be age; the pper pa t, ab ve the i Atok n in homi i s s uh o s ons to a . Wata gl merate , c idered be age The g re t conformably on the Redwall Limes tone and i s conformably overlain by an k h on the M a ac a Formati .

MANAKACHA FORMATION

The M anakacha Formation i s named from Manakacha Point on the f n n i s s o H su n o o u . s s s ea t ide ava Ca y , directly ab ve S pai village Thi pelli g

o n to o o u us on o o of u acc rdi g U S . Ge l gical S rvey age t p graphic map S pai

u dr n on o H su M s o 1 9 us s q a a gle , Ariz a; the fficial ava pai ember hip R ll , 72, e ” th e spelling M anakaja for the Indian family of that name . The type s on of o on is on ns in ecti the f rmati al g the Apache trail , which begi the

n M anakacha village a d winds up the canyonside toward the point . The consis ts of the lowes t mass ive cliff in the Supai Group and also the small n or s n ons s s be ch lope above it (lower cliff unit and middle s lope u it) . It c i t of crossbedded limy sands tone or sandy limes tone with minor amounts of i i on u s on . s s on o on a hom o m d t e It re t c f rmably the W ta g F rmati , the boundary in mos t places being indicated by a change from s lope below to cliff above and by the presence of the lowermos t sands tones of the M naka h n f n i n un on o a c a . The upper bou dary o the formatio s a c f rmity marked by a surface of erosion and by a basal conglomerate of the Wesco ame o n of Man kacha un is Atokan on g F rmatio . The age the a cliff it , th n e basis of diagnos tic fusulinids ranging throughout the Grand Canyo . The upper part ( s lope unit) is either Atokan or Des Moinesian in age; os s s u n of f il th s far found in it are not unequivocal evide ce either .

WESCOGAME FORMATION

The Wescogame Formation is named from Wescogame Point on the

s s of H su n on ou s s of u and we t ide ava Ca y , ab t 3 mile outhwes t S pai village o Hu n on o n s n n directly ab ve alapai Ca y , d w which the pre e t mai Hu o s to oo s on of ( alapai) h r e trail the village passes . A g d ecti the o on i s os on s t bu t the s on is on f rmati exp ed al g thi rail , type ecti the Apache no n n f s trail farther rth . The Wescogame is composed domi a tly o ma sive crossbedded s n s on or s n s on o s o n n a d t e a dy lime t e which f rm a pr mi e t cliff, bu t n u s u it i cl des abou t half the s lope ( upper s lope unit) above . Thi pper slope is not represented at the type section but is present nearly every s ih n n n Mu s on i s n but not ro where el e Gra d Ca yo . d t e s pre e t p THE SUPAI GROUP— SUBDIV ISION AND NOMENCLATURE J5

n Wesco ame o i on l s portionate ly abundant in the formati o . The g F rmat

of n s n usu n s and o s . s s probably V irgilia age , a i dicated by f li id c ral It re t unconformably on the Manakacha Formation and is unconformably n beneath s trata of Wolfcampian age in the E splanade Sands to e .

ESPLANADE SANDSTONE

The geologic unit Esplanade was called by White ( 1 929) the Esplanade Sands tone Member of the Supai Formation; in the present report the os o on of Esplanade i s raised toformation rank . I t i s the upperm t f rmati

the Supai Group . The geographic term Esplanade comes from the E splanade plat form that i s a prominen t bench in the wall s of the Grand Canyon; i t I S

‘ especially wide and conspicuous in the wes tern part . The term

“ ” n 1 8 n n u to n n on . . u o 8 Espla ade was i trod ced the Gra d Ca y by C E D tt ( 2, 8 1 1 in n to s n is in u os p . 7, 2 ) referri g thi be ch , which carved the pperm t r Sub s n s on s of u in hi s s on of the Torowea . a d t e bed the S pai , de cripti p a ea sequent references to the E splanade platform were made by Davis ( 1 901

nson 1 1 o 1 14 1 8 1 1 9 . on o 9 1 . 9 . 3 2 R bi ( , p N ble ( , p , 2 , 7 ; 2 , p Dart n 1 5 . n n was to s 9 a d o s . u n ( 2 , p ther Eve t ally , the ame applied the a d “ s on i o s n : for on n n of n ou of t e th t f rm the be ch c ve ie ce refere ce , the gr p hard sands tones which supports and forms this shelf is termed the ‘ ’ ” 1 n M f u o n 929 . E splanade Sands to e [ ember o S pai F rmatio ] (White , , p “ 1 and the u 0 of u - s n s on s l ) pper 27 feet the S pai , hard, dark red a d t e are ”

no n o s s n s n s on to anow 1 936 . k w l cally a the E pla ade a d t e (S y , , p The formation cons is ts primarily of very fine grained cross -s tratified s n s on n u s s oun s of s s on a d t e that forms mass ive cliffs . It i cl de mall am t ilt t e and u s on t n o s o s n s or ss s and in m d t e that wea her i t l pe , be che , rece e , f s n n n on on ns so ns s o su . we ter Gra d Ca y , c tai me exte ive bed gyp m Near

n s in s n of n n on Gra d Wa h Cliffs the extreme we ter part the Gra d Ca y , it apparently interfingers with the P akoon Limes tone of McNair ( 195 1 ) un s n for s o on i s der Shivwits Plateau . The type ectio selected thi f rmati on ss s o nn n on of H su al g the Apache trail , where it pa e fr m the i er Ca y ava to the broad E splanade platform bench occupied by the Hermit Shale . is un n The Esplanade Sands tone is of Wolfcampian age . It derlai n n nn n n u co formably by the WescOgame Formation of Late Pe sylva ia age . The boundary i s marked by a well -developed surface of erosion with some channel s more than 40 feet deep and by a pers is tent limes tone -pebble

on o s n is o n H of c gl merate . The E pla ade verlai by the ermit Shale L eonardian age and separated from it in many places by a greatly channeled surface of eros ion .

CORRELATION WITH PREV IOUS SUBDIV ISIONS

u s u n to o o o of M s but n n n of his S b eq e t the t p graphic w rk atthe , i depe de t

o s ons 1 . 1 u an n o ss . 9 6 s s b ervati , L F . Noble ( 22, p ) gge ted i f rmal cla i JG CONTRIBUTIONS TO STRATIGRAPH !

in o n su s ons B and fication of the Supai which he rec g ized bdivi i A , , C ,

His su s on i s s as s s o from top to bo ttom . bdivi i C de cribed the ba al l pe “ ” beginning with a plane of unconformity by eros ion on top of the Red f s n s on s and s on in ou u wall and consis ting o a d t e , hale , lime t e ab t eq al

s s to u n to Watahomi i o on . amounts . It eem be eq ivale t the g F rmati

’ Noble s subdivision B is described as crossbedded sands tone below the

ss and s o . n middle and underlying a thick ma ive cliff ledgy l pe Appare tly , it i s composed of both the M anakacha and Wescogame Foramtidns of “ ” n o o n u s o un n u prese t usage , t gether with the verlyi g pper l pe it ;it i cl ded w s kan V n and Wolfcam ian . ou a rocks of A to , irgilia , p age Alth gh he aware of the widespread conglomerate and eros ion surface at the base of 61 u n o 1 9 . the E splanade Sands to e , he (N ble , 22, p ) placed the pper — boundary higher at the base of the Esplanade cliff .

’ Noble s subdivision A is nearly equal to the E splanade Sands tone of

i s s as present usage bu t did no t include the basal s lope . It de cribed containing sands tone and some sandy shale . Pas t and present terminologies are summarized and compared in the table giving class ifications of Supai s trata .

S ummary of pas t and pres ent clas s ifications of S upai s trata

o lf c a mpia n

E ros io n

V i rgil ia n

A t o k an

T! PE SECTION OF SUPAI GROUP IN HAV ASU CAN! ON

Wata homi i Form io me sured on wes s ide of c o N v o F s; Ne r S u i V i e Coco i o Cou Ar iz . [ a pa llag , n n nty , g at n a t any n at a aj all u er r of S u i Grou me s ured o A che r i or he s of vi e pp pa t pa p a al ng pa t a l , n t a t llag ] Hermi t Shale ts t n t - s - n t n- - n ; and Sil o e , modera e reddi h ora ge , hi bedded , ledge formi g grayish -red s tructureless slope -forming muds tone; toge ther form

c . ledge-s lope member THE SUPAI GROUP— SUBDIV ISION AND NOMENCLATU RE

n n s n s u t 0 9 44 t . ns s ts s t t U co formi ty . Ero io rface wi h relief fee Co i of i ola ed pla eaus of resis tant sands tone tha t rise above generally flat surface

of formation .

Supai Group— E splanade Sands tone Esplanade cliff uni t: n s t n ss s s u s s s en Sa d o e , ma ive; form re id al hill or me a; ri e above g ‘ su at n t t eral rface A mile orth . E s ima ed

n s t n t - n - n n n t - Sa d o e , modera e ora ge pi k , very fi e grai ed , hick bedded , massive; form s receding round ledges at top of main n st n t - n - n n - n 24 nt to Sa d o e , modera e ora ge pi k , fi e grai ed ( perce ) very n n 57 nt s t us t fi e grai ed ( perce ), ligh ly calcareo , very hick bedded 1 0—20 ft ss t s to n s s ss ( ), ma ive; locally wea her pi ki h gray; form ma ive

n s t n t - s - n n n con Sa d o e , modera e reddi h ora ge , very fi e grai ed , friable; tains medium -scale wedge planar cross -stratification (planes 1 — 1 0 ft long) n s t n t - s - n n n t n to t Sa d o e , modera e reddi h ora ge , very fi e grai ed , hi hick 1 —4 ft t- ss s s t nt t n un n un t bedded ( ), fla bedded; le re i a ha derlyi g i ; upper part contains several 2 to 3 -ft beds of pale-red calcareous s ands tone; forms cliff or receding ledges

n st n and s t n . s t s n s t n is s n Sa d o e lime o e Uppermo a d o e pale reddi h brow ,

n to n n us nt t s n s t n fi e very fi e grai ed , calcareo , friable; i ermedia e a d o e

is t s n n n us s t s modera e reddi h ora ge , very fi e grai ed , calcareo , il y; ba al i n s t n s s t elastic s t out on su . lime o e pale red, il y , ; grai e ched rface The three uni ts form cliffs separated by prominent parting planes; all contain medium -to large-scale cross -s tratification; contain local festoon s tructures; weather wi th black varni sh

n s t n - s - n n n us 6 Sa d o e , pale reddi h brow , very fi e grai ed , calcareo (2 per

nt s t 19 nt t- s ss t n ce ), il y ( perce ), fla bedded; form rece be wee major cliffs n s t n t - s - n n n 75 n t of Sa d o e , modera e reddi h ora ge , very fi e grai ed ( perce ns us nt ns su n u to subrounded ns grai ), calcareo ; co ai ba g lar grai ; ss s t u tu ss nt ns t n n of t - s ts t n ma ive, r c rele ; co ai par i g zo e fla bedded il o e that separates uni t into two parts; forms base of Esplanade cliff

To ta l E splanade cliff um t

E splanade s lope uni t

n st n t - s - n n n un to Sa d o e, modera e reddi h ora ge, very fi e grai ed (ro ded subrounded us t n- 2—3 ft s tru tu ss nt ns ), calcareo , hi bedded ( ), c rele ; co ai several pale-red calcareous sil ts tone partings; forms reces s below mas sive cliff

n s t n t - s - n n n s t t n Sa d o e , modera e reddi h ora ge , very fi e grai ed, il y;very hi to thin-bedded ( 1 —4 contains irregular to fes toon-type s truc tures; form s weak ledge

n t - u s nn s in un Co glomera e , pale red , irreg larly bedded; fill cha el der n un t - s s s t nt . t : n s n lyi g i ; form re i a ledge Ma rix pale red fi e a d . Gravel t s t s — 1 i h u t 3 in . diame er of mo pebble . ; maxim m diame er ; pebbles subrounded to un s t s - t ro ded;poorly or ed;compo ed of olive gray , ligh and - s n gray , pale red lime to e and sil ts tone

n s t n t - s - n n n s n Sa d o e, modera e reddi h ora ge , very fi e grai ed; ome fi e n s t t n to t n- 1 —4 nt ns u grai ed; il y , very hi hi bedded ( co ai irreg lar to fes toon-type s tructure; forms slope wi th weak ledges J8 CONTRIBUTIONS TO STRATIGRAPH!

— Supai Group— E splanade Sands tone Conti nued — E splanade s lope uni t Continued st n t- n s - n t to n n sur Lime o e , ligh brow i h gray , apha i ic very fi e grai ed; n s s u s t nt ns t n n s face marki g gge algae; co ai hi , locally developed ba d wo t t s t n s in and 0 in. s t of cher ; form hi bed (6 . 2 ) epara ed by gray

- - t n 0 in . t t n s il ts o e (2 hick) and capped by 8 in . hick bed of co cre tion ary limes tone

n s t n ra ish~ oran e ~ ink n n t n Sa d o e , g y g p , very fi e grai ed , very hi bedded (ii—2 flat-bedded; forms receding ledges s t n - n t n n u s s - Lime o e , pale red, co cre io ary , very hard; i cl de grayi h red s il t; form s rounded ledge or s lope n s t n - s - n n n s t n- t Sa d o e , pale reddi h brow , very fi e grai ed , il y; iro coa ed; ns tt s t u tu ss . grai bri le; r c rele ; forms s lope .

n s t n - n n s t s tru tu ss u l Sa d o e , pale red , very fi e grai ed , il y, c rele , cr mb y form s s lope n s t n s - n n n n u a s t t n Sa d o e , grayi h pi k , very fi e grai ed (a g l r), il y , hi bedded ( 1 —2 ft); weathers to rounded ledge

n st n s - n - n n n ous Sa d o e , grayi h ora ge pi k , very fi e grai ed , calcare , friable; form s n st n n un t bu t s nn Sa d o e , like overlyi g i fill cha el

n t - to t- s t n at tt f Co glomera e , pale red ligh gray; form hi bed bo om o - - n n t t r s t . : n eros io chan el . Matrix : pale red o ligh g ay il Gravel ge eral t n — i in n . u t s t diame er ra ge 0 5 2 ; maxim m diame er 3 . ; mo ly sub un un s un os of t- ro ded , few ro ded , ome well ro ded; comp ed ligh gray limes tone and reddish -brown and purplish -gray s il ts tone

Total E splanade slope uni t wi th basal channel sands tone and n co glomera te .

To tal E splanade Slope uni t excl uding two basal channel uni ts

To tal E splanade

n n 4 f cut nt ss t . nn ft and 1 4 t U co formi y Cha el , here deep wide , i o ma ive and crossbedded s n s t n s n tw u a d o e ; filled wi th overlyi g o ni ts .

Supai Group— Wescogame Formation s un t: Upper lope i Not recogn ized at this locali ty . Middle cliff uni t

n s t n n s r t s us t - n s o ts at s n Sa d o e; pi ki h g ay wi h mall r y brow p ba e , gradi g upward to pale red; fine to very fine grained;calcareous; thin bedded — (2 4 ft) at base and at 50 ft above base; el sewhere very thick bedded 1 0— 1 5ft t nn s nt n t n t s nt n ( ); hi er bed co ai fla lami ae , hicker bed co ai large -scale planar cross -s tratification ( up to 50 ft long); contai ns two dark -reddish -brown lenses of flat-bedded s il ts tone at 55 ft and ft above base; weathers wi th dark -brown varnish; form s mass ive

u s t n t- n n n us t n- - 2 ft t M d o e , ligh brow , o calcareo , hi bedded ) fla bedded; contains abundant Riv ularites; form s recess at base of cliff

n s t n t - s - n n n us Sa d o e , modera e reddi h ora ge , very fi e grai ed , calcareo , shaly to s tructureless; forms s lope wi th weak ledges ; fill s U pper part of large channel in older Pennsylvanian rocks n st n t - s n n - n to n n Sa d o e , modera e reddi h ora ge; fi e grai ed very fi e grai ed ,

us t - n u mud ts and s tt s calcareo , fla bedded; i cl des pelle ca ered pebble near base; form s s lope ; fill s channel bo ttoms

Tota l middle cliff uni t wi th basal channel sandstones THE SUPAI GROUP— SUBDIV ISION AND NOMENCLATURE 9 ,J .

Supai Group- Wescogame Formation— Continued Middle cliff uni t— Continued Total middle cliff uni t excl uding basal channel sands tones

Tota l Wescogame Formation

n W nn s t un tt s cut to t s as u Unco formi ty . ide cha el wi h ro ded bo om , dep h m ch as 80 ft in cross -s tratified sandstones of older Pennsylvanian age

x n i (here ft deep);e posed at thi s horizon at ma y places n vicini ty .

Supai Group— Manakacha Formation Middle s lope unit: n t n t - s - n n - n to n n Sa ds o e , modera e reddi h ora ge, fi e grai ed very fi e grai ed; cross -s tratified on large scale ( up to 40 ft long); i ncludes grayish red muddy noncalcareous very fine grained sands tone near base; uni t forms s lope

t s un t - s n To al middle lope i , pre ero io

Lower cliff um t

' s t n s - n - n n n subrounded s t Lime o e , grayi h ora ge pi k , very fi e grai ed ( ), il y , (insoluble 33 percent); cross -s tratified on small to medium scale; wea thers wi th black varni shed surface; form s massive resi s tant cliff wi th rounded edges n st n - - u n n s t n ss Sa d o e , pale red p rple , very fi e grai ed , limy; ro gly cro

s t t t u n s ts 2— 3 ft t nt ins s s t n ra ified ( ab lar pla ar , e hick); co a ome lime o e ns le es; form s cliff or receding ledge .

- n st n and s ts t n . n s t n u n n Sa d o e il o e Sa d o e , pale red p rple , very fi e grai ed; locally massive and thick bedded wi th limes tone lens es ; grades downward i nto pale-reddish -brown calcareous shaly to thin-bedded sil ts tone; in terval forms receding ledges s t n s - u s u n s n ns u 40 Lime o e , grayi h red; incl de m ch very fi e a d (i ol ble 4 percent); crossbedded ( tabluar planar); sets medium thick ( 1 3 ft); contains jasper near top; forms receding ledges s t n u - t- r n tt Lime o e , medi m ligh g ay; i cl udes sca ered very fine grained to fine-grained sand; cross -s tratified (medium scale); contains abun dant chert and jasper;wea thers to rough black s urface; forms prom inent ma ssive cliff Limes tone; light brownish gr ay wi th pale-red blotches; thick-bedded (4— 1 5 ft); contains jas per layers and veins near base; cross -s tratified (medium scale); forms cliff ts t n - s - n us 22 nt u s ts Sil o e , dark reddi h brow , calcareo ( perce ), cr mbly; re on irregularly channeled surface of brigh t-red muds tone Total lower cliff uni t

To ta l Manakacha Formation

s n s u t u tu ss s - n s u is nn Ero io rface . S r c rele reddi h brown s il ts to e rface cha eled to — dep th s of 1 2 ft a t irregular interval s and locally removed entirely n by erosio . — Supai Group Watahomigi Formation: Lower s lope uni t: Concealed slope

n s t n - s - n n n n n us Sa d o e , pale reddi h brow , very fi e grai ed , o calcareo , s truc tureless; forms conspicuous marker bed; wea thers into rounded ledge overlying weak cliff

tst n s - u to t- Sil o e , grayi h red , m ddy , very limy , wavy fla bedded, lami nated contains thin jasper lenses a t top; form s weak cliff J l O CONTRIBUTIONS To STRATIGRAPH!

Supai Group— Wata homigi Formation— Continued Lower s lope uni t— Conti nued

Mu s t n - s t us to t- n te d o e , pale red , il y , calcareo , wavy fla bedded , lami a d ‘ ‘ (A—x i form s steep s lope Concealed s lope; probably grayi sh -red mudstone n t and s t n u - a - n t n con Co glomera e lime o e , medi m d rk gray , co cre io ary; tains some jas per and lenses Of intraforma tional limes tone pebbles ; form s rounded ledge or s teep s lope; marks base of Atokan s tra ta

s t n t n s n s t nta ns un a nt Lime o e , very ligh gray , mag e ia , very il y; co i ab d elongate concretions and lenses of gray cher t; forms ledge at top of series ts t n - s n Sil o e , dark gray , friable; form be ch

s t n t s t n - n t - e 2—6 ft Lime o e, very ligh gray , il y , fi e grai ed, hick bedd d ( ); contains thin jasper layers and crosscutting veins throughout; form s series Of ledges separated by thin —l ft) muds tone beds s t n t- n s - t nt th Lime o e , ligh brow i h gray , dolomi ic; i erbedded wi black muds tone containing network Of calci te veins; wea th ers to concre tionary spheres; forms s lope

s t n e u - n - n nt ns un nt s Lime o e , m di m gray , fi e grai ed; co ai ab da ja per layers and secondary calcite fillings along fractures ; weathers to

s t n t- n s - s t th s n s Lime o e , ligh brow i h gray , il y; wea er brow ; form weak

s t n s - u nt e t n Lime o e , grayi h red , irreg larly bedded; i erbedd d wi h brow muds tone; forms s lope n t and s t n u - t- s t nta ns Co glomera e lime o e , medi m ligh gray , il y; co i local jasper lenses and lenses Of dark intraforma tional limes tone pebbles t nt s in . t to n s s s s (max . ) a p of u i t; form s erie of re i a ledge - - Mu s t n u s t us u r s s . d o e , pale red p rple , ligh ly calcareo , cr mbly; fo m lope

s t n u - t- n - n nt ns t n u Lime o e , medi m ligh gray , fi e grai ed; co ai hi irreg lar jasper layers ; cons i s ts Of a s i ngle very thick bed; form s res is tant cliff Concealed talus s lope ts t n - s n s s Sil o e, pale red, haly; largely co cealed; form lope

- n t t s s s t nt . Co glomera e , pale red, very hick bedded; form re i a ledge - - n n Ma trix: pale red very fine grained to fine grained sa ds to e . Gravel : - 3 n in t n u to su n u r s Of mos tly 14 4 i . diame er; a g lar ba g la ; compo ed - s - n t - n - n and t dark reddi h brow , modera e ora ge pi k , very dark red cher and flint Concealed mpe ts t n - s ss n t st n s Sil o e , pale red, haly , fi ile; lami a ed lime o e bed in s . ) cattered throughout interval; form s

n te k- s - n t n- to s un t s Co glomera , dar reddi h brow , hi bedded haly; i form

- t : n n s t n and s ts t n . ledge . Ma rix pale red very fi e grained sa d o e il o e : un nt $64 4 in i . n t s t u Gravel ab da diame er pebble , wi h a maxim m - nd t Of ii in . s t a diame er ; compo ed Of very ligh gray , pale red , dark t to Of gray chert; abundant brachiopods ( Compos ita sp . ) a p

- n t ss un t s e . Co glomera e , pale red , ma ive; i form l dge - - i 3 6 in . n t t t : u s t n . : st Ma rix pale red m d o e Gravel mo ly diame er , wi h

x u t in u s t n nt ma im m diame er Of 8 . irreg larly haped wi h ra dom orie a tion; composed of ligh t-Olive-gray and da rk-reddi sh -brown s t n s - n ti t - 2—4 ft t s Lime o e , yellowi h gray , apha i c , hick bedded ( ); wea her to very pi tted surface; forms ledge