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 .