Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Southeastern Arizona and Southwestern New Mexico

I

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By AUGUSTUS K. ARMSTRONG and BERNARD L. MAMET

U.S. GEOLOGICAL SURVEY BULLETIN 1826 DEPARTMENT OF THE INTERIOR DONALD PAUL HODEL, Secretary

U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director

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Library of Congress Cataloging-In-Publication Data

Armstrong, Augustus K. Mississippian (lower carboniferous) biostratigraphy, facies, and microfossils, pedregosa basin, southeastern Arizona and southwestern New Mexico.

(U.S. Geological Survey bulletin ; 1826} Supt. of Docs. no. : I 19.3:1826 Bibliography: p. 1. Paleontology-Mississippian. 2. Paleontology­ Pedregosa Basin. 3. Paleontology-Arizona. 4. Paleontology-New Mexico. I. Mamet, Bernard L. II. Title. Ill. Series. QE75.B9 no. 1826 557.3 s 88-16040 [QE729.2] [560'.1'72709791] CONTENTS

Abstract 1 Introduction 1 Previous studies 1 Stratigraphy 4 Lower boundary of the Mississippian 8 Units overlying the Mississippian 8 Escabrosa Group 9 Keating Formation 9 Bugle Member 9 Witch Member 10 Hachita Formation 11 Paradise Formation 13 Western facies of the Escabrosa Limestone 15 Rancheria Formation 16 Summary of the lithologies of the three regional facies 17 Lithologies of the western facies 17 Lithologies of the central facies 17 Lithologies of the eastern facies 18 Microfossils, foraminifers, and calcareous algae 18 Biostratigraphic correlations 18 Mississippian carbonate facies and paleotectonics 19 Conclusions 24 References cited 24 Supplementary data: Detailed biostratigraphy 30 Index 39

FIGURES Frontispiece. Photograph of northeast side of the Big Hatchet Mountains, N.Mex. 1. Index map of New Mexico and eastern Arizona 2 2. Map of New Mexico and eastern Arizona, showing Mississippian and earliest Pennsyl­ vanian regional tectonic features 3 3. Correlation chart for the Mississippian System of New Mexico, eastern Arizona, western Texas, and southwestern Colorado 4 4. Correlation diagram showing microfacies and microfossil zones in the eastern, central, and western facies 6 5-8. Photographs of: 5. Northeast side of the Boss Ranch section, Pedregosa Mountains, Ariz. 9 6. Escabrosa Group on the north side of Blue Mountain in the Chiricahua Mountains, Ariz. 10 7. Typical dark-gray chert of the Witch Member of the Keating Formation in the Blue Mountain section, Chiricahua Mountains, Ariz. 11 8. Contact between the Witch Member of the Keating Formation and the Hachita Formation 12 9. Time-stratigraphic chart for the Paradise Formation 15 10. Stratigraphic chart of Mississippian microfossils in southwestern New Mexico and southeastern Arizona 20 11. Isopach map of western New Mexico and eastern Arizona for Lower Mississippian zones pre-7, 7, and 8 23 Contents V 12. Idealized sequence of standard facies belts for the Escabrosa Group, Escabrosa Limestone, Lake Valley Limestone, Las Cruces Formation, and Rancheria Formation 24 13. Block diagram illustrating facies environments and lithostratigraphic units in the Mississippian of southern New Mexico and southeastern Arizona 26 14. Isopach map of western New Mexico and eastern Arizona for Late Mississippian (Meramecian) zones 12 through 15 27 15. Cross sections illustrating Mississippian regional stratigraphic relations across the Pedregosa Basin 28

VI Contents Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Southeastern Arizona and Southwestern New Mexico

By Augustus K. Armstrong and Bernard L. Mamet 1

Abstract western New Mexico, and southeastern Arizona (figs. 1-3). Our investigation of the Mississippian outcrops, carbonate Initial Lower Mississippian deposits of southwestern New rocks, microfossils, and microfacies in the Pedregosa Basin Mexico and southeastern Arizona are early Tournaisian (pre­ zone 7) in age and rest unconformably on rocks of Late Devonian and adjacent areas is based on field studies from 1956 to 1978. age. Mississippian sediment was deposited during a marine The thin sections on which microfossil and petrographic transgression across an erosional surface of very low relief. analyses were done are deposited in the U.S. National Museum Early and middle Tournaisian marine transgression began in in Washington. Calcareous algae and foraminifers are used to southwestern New Mexico and adjacent parts of Arizona, de­ construct regional correlations among the stable-shelf-plat­ positing the Keating Formation of the Escabrosa Group and, to form carbonates, the somewhat deeper water, crinoid­ the west, the lower part of the Escabrosa Limestone on a shoal­ bryozoan bank carbonates, and the semi-starved-basin, ing subtidal to supratidal carbonate platform. By the end ofTour­ spiculitic carbonate facies. naisian (late Osagean) time, epicontinental seas had flooded Specific descriptions, and the locations of outcrop sections much of New Mexico and Arizona. The Hachita Formation of described in this report, are shown adjacent to the stratigraphic the Escabrosa Group in the Pedregosa Basin was deposited in sections that form the regional diagram (fig. 4). The locations shoaling water as crinoidal sand on a wide carbonate shelf. To the west in Arizona, the stratigraphic equivalent of the Hachita of outcrop sections not discussed in this report but shown on Formation is the upper part of the Escabrosa Limestone, com­ the index map of New Mexico and eastern Arizona (fig. 1) can posed of peloid/calcareous-algal micrite deposited in subtidal to be found in the reports by Laudon and Bowsher (1941, 1949) intertidal environments. A major regional marine regression and and Armstrong and Mamet (1974, 1976). The microfossil ensuing transgression that took place during early Visean (in part zonations established and described by Sando and others Meramecian) time are represented by a hiatus in the upper part (1969) and Armstrong and Mamet (1977) are used in this of massive encrinite of the Hachita Formation in southwestern report, along with Dunham's ( 1962) carbonate-rock classifica­ New Mexico. This hiatus is expressed in the unconformity be­ tion. tween shelf carbonates of the Lake Valley Formation and deeper­ Acknowledgments.-We thank Frank E. Kottlowski, direc­ water, basinal carbonate rocks of the lower part of the Rancheria tor of the New Mexico Bureau of Mines and Mineral Resour­ Formation in south-central New Mexico. In southwestern New Mexico and adjacent parts of Arizona, the Paradise Formation ces, for his continuing support of this project. Kenneth E. represents shallow-marine sedimentation that ranges in age from Caster, formerly of the University of Cincinnati, suggested this zone 15 (late Meramecian) through zone 19 (late Chesterian). study to Armstrong in 1956 and supported his efforts in the The upper part of the Rancheria Formation and the Helms For­ study of corals and brachiopods. We are grateful to James Lee mation of south-central New Mexico and western Texas are a Wilson, formerly of the University of Michigan, and Robert deeper-water facies of the Paradise Formation. N. Ginsburg of the University of Miami for many hours of con­ Over the entire region, Lower Pennsylvanian sedimentary versation and discussion on carbonate depositional models and rocks truncate Mississippian sedimentary rocks of Tournaisian, diagenesis. James Lee Wilson, Sam Thompson III, John E. Visean, and Namurian age. Repetski, and J. Thomas Dutro, Jr., reviewed the manuscript; we appreciate their time and help in greatly enhancing the quality of this study. INTRODUCTION

This study describes the stratigraphy, carbonate facies, paleotectonics, and micropaleontology of the Mississippian PREVIOUS STUDIES rocks in the Franklin Mountains of western Texas, south- Fossils from Mississippian rocks of New Mexico were first identified by White (1881) at Lake Valley, N.Mex. Cope

Publication authorized by the Director. U.S. Geological Survey, October 5, 1987. (1882a, b) referred to the rocks at Lake Valley and proposed 1 University of Montreal, Quebec, Canada. the name "Lake Valley formation." Herrick ( 1904) used the

Introduction name "Kelly limestone" for the Mississippian rocks of the The Escabrosa Limestone of Mississippian age was named Magdalena mining district. Laudon and Bowsher (1941, by G .H. Girty (in Ransome, 1904) for the lower Carboniferous 1949) divided the Mississippian System of south-central New section in the Escabrosa Cliffs, west of Bisbee, Cochise Coun­ Mexico into five formations and the Lake Valley Formation ty, southeastern Arizona. Huddle and Dobrovolny (1952) into six members (fig. 2). They named the Caballero Forma­ made a regional stratigraphic study of the Devonian and Mis­ tion for rocks of Kinderhookian age in the Sacramento and San sissippian strata of central Arizona that included the northern Andres Mountains and the area around Lake Valley, N.Mex., parts of the Escabrosa Limestone. They described and il­ and applied the names "Las Cruces and Rancheria Forma­ lustrated the Mississippian erosional surface and the effects of tions" to Meramecian rocks in the Hueco and Franklin Moun­ pre-Pennsylvanian solution activity. Gilluly and others tains of western Texas and in the San Andres and Sacramento (1954) established the nomenclature for the upper Paleozoic Mountains of New Mexico. They restricted Beede's (1920) rocks of Cochise County, Ariz., which also included the Mis­ designation of the Helms Formation to beds of Chesterian age. sissippian System. Sabins (1957) described the Escabrosa Kues (1986) published a detailed faunal list for the Caballero Limestone and the Paradise Formation in the Chiricahua and Lake Valley Formations west of the Rio Grande. Mountains. Armstrong (1962) described the megafossils and

110° 109° 1oao 107" 106° 105° 104° 103°

37".

36°

··it~ ~ After Foster and ~ 35° others (1972) ; 0~---:---···,,

fl -·------' ~~ -- ~- - .. ' '

34°

l- 33° After Meyer (1966) ~~I \ I

32°

0 50 tOO 150 200 KILOMETERS

Figure 1. Index map of New Mexico and eastern Arizona, showing locations of outcrop sections used in this report (triangles) and in biostratigraphic and lithologic regional-correlation diagram (numbers; see figs. 4, 15). Contours (in feet; queried where uncer­ tain), isopachs of the Mississippian System. IFZ, lower Paleozoic rocks. Section line 8-B' is dotted.

2 Mississippian (lower Carboniferous) Biostratigraphy, Fades, and Microfossils, Pedregosa Basin, Arizona and New Mexico stratigraphy of the Escabrosa Limestone in the Chiricahua the east side of the Chiricahua Mountains. Hernon (1935) Mountains of southeastern Arizona and southwestern New described and illustrated the macrofauna of the Paradise For­ Mexico. He locally elevated the Escabrosa Limestone to mation at Blue Mountain in the Chiricahua Mountains. Mc­ group rank and divided it into two formations: the Keating Kee (1951, pl. 1) published the first detailed paleotectonic Formation, with two informal members, A and B; and the discussion and isopach map for the Mississippian System of overlying Hachita Formation. Armstrong and Mamet ( 1978a) New Mexico and Arizona. Zeller (1965) published M.K. formally named these two informal members of the Keating Elias' extensive macrofossil list for the Paradise Formation of Formation, in ascending order, the Bugle and Witch Members. the Big Hatchet Mountains. Armstrong and Mamet (1978a, Stoyanow (1926) named the Paradise Formation for out­ b) and Armstrong and others (1979, 1980) published short crops a few miles east of the old mining camp of Paradise, on papers on a regional correlation of the Mississippian System

112° 1110 110° 109° 108° 107" 106" 105° 104°

r' • • 1------L ~" I

ARIZONA

BLACK MESA 36° ______!_ --,'-.}_ '------c-<1:4;_~ i BASIN .s-~<>ol\1 t LA~E PALEOZOIC. TCi> CENOZOIC ;

35" TO HQLOCENE ' ! 4--+--...... -- I PEr,INSYLVANt. N_-MlSSISS\PP\AN-~ I ! I I i i 34° L __ _ i \ i 0~ i--- : : ! : ~~ ·~ i I _____ \ ~-···· :_,'( ___ 1 ·J:--~ -- --~ r· : I i ~ \ I A i------_L --:, • \ 33° i i. • ' \-­ i "\ t i r·-. • • \ ~ \ I I • L .. ----: i : I j ~ - ~1- ---·: I r • \S\ -- ---~'--1 : PENNSYLVANIAN RANC~ERIA i ' "'o• j : \ FLORIDA UPLIFT BASIN , 32" . • Mississi*-·~an car~nat:~ LATE ~ISSI~SIPPIAN f.-)_·-~----·-·-·-·:-·-·-·-;'\~.. -·-·:- 6 .• ( s elf basil'\----\ STARVEni BASIN "· •· '-~ ' ...,,... :PEDREGO Ai·-·-·----~----·-· -·\.,_\ I '~ - .._- - 6 ...... 1 ~ BASIN ~ ! MEXICO \ ~EXAS ...... _ : • ..O.q~~ I \.,. •, I -...... ______; _____ ~---·-·-·l.._??ok".j ''""'\ I '· /

0 50 100 150 200 KILOMETERS

EXPlANATION

Anticline+ Syncline+ Showina plunge

Figure 2. New Mexico and eastern Arizona, showing Mississippian and earliest Pennsylvanian regional tectonic features. Triangles, locations of outcrop sections used in this report.

Previous Studies 3 of southwestern New Mexico and southeastern Arizona. STRATIGRAPHY Armstrong and others (1984) documented the Mississippian­ Pennsylvanian transition and hiatus in the Pedregosa Basin of The stratigraphic sections described in this report were sys­ southeastern Arizona and southwestern New Mexico. tematically measured and sampled at 1- to 1.7-m intervals for

This report Q) c: 0 c: N ca E' Q) Q) ~.!! c. en -~ en :;; 0 ca 0 I >CI) en (/.) :5 LU - ~ -(.l ~

c: c:"' -~- ""::::1 • 0~ ..c:caJ2t en C. ca- j§ al 0 N

c: 19 -~-f--.--- :5 ~ 18 ~~f--.--- 2 17

16s l---- 16i - 15 Escabrosa --- Escabrosa Escabrosa Limestone Limestone Limestone c: jpart) jpart) jpart) ca 14 Q) - en Reworked regolith > 13 with boulders - 12 1------c.. ::::1 11 0 Sectoon cut by ? ? [,. t5 - Cenozoic fauh ? ? .. 10 9 - Mooney FaHs Mbr 8 -fii,jiidel-, ~ 1_St>!!!'&!~b!o_l c: "' "'c: "'"'"' c: "'c:"' ca e.s e.s "'"'"' c: 0"' 0 ·u; .Q "' .Q "' ~~ .cu; Escabrosa Escabrosa "Cii :.:::;~ ~.5"' "' "' "' "'"' "'~ .5"' Limestone Limestone c: 7 UJ _. ~:§ ~:5 ..... _. :5 Whitmore jpart) jpart) 0 Wash 1- Member

Pre-7 r1 ·1Tn rr TTin II II Tin riTil llf TTITI !II nIll rT II llllYII JJ Ll u LLLI-J._LWJ.Uj_ Rocks w...l!-l.I_UIAJJLL!Jl__.lj_l )jllJ_J_IIJ-.LliJ..L 1.1 J.l_J---Jl..LJ lL!.JJ l...ul U.-~.._.l!~~I..J...~--ucr..v~.Jr-<..'"'t~~ J I ILl IJ I I Perch a beneath !Devonian) IIDevonian) IDevonian) IDevonian) IDevonian) IDevonian) IDevonian) IDevonian) IDevonian) Mississippian Shale Martin Martin Martin Martin Martin Martin Martin Martin Martin Upper System Formation Formation Formation Formation Formation Formation Formation Formation Formation IDevonian) i

Figure 3. Correlation chart for the Mississippian System of New Mexico, eastern Arizona, western Texas, and southwestern Colorado. Krukowski (1988) reported a Kinderhookian age based on conodonts for the Caloso Member of the Kelly Limestone in west-central New Mexico. Wavy line, unconformity (queried where uncertain); arrow, direction of relative movement along fault.

4 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico carbonate petrographic studies, microfacies analysis, and mi­ Mexico and southeastern Arizona. The outcrop sections are: crofossil zonation. The principal stratigraphic diagram forms in western Texas, Vinton Canyon in the southern Franklin a line of measured sections (A-A', fig. 4) that starts near El Mountains, just north ofEl Paso; in southwestern New Mex­ Paso, Tex., and extends westward across southwestern New ico, the Florida Mountains, Klondike Hills, and Big Hatchet

lane 11 974), !Laudon and Bowsher 11949) This report Yurewi·cz 11 977), K k. d h 1 ' Armstrong and Mamet 11974, 1976) 1 I I Laudon and Bowsher n949) ott ows an ot ers 1963) Q) c: 0 N 0 ·.:(I)"' - ·~ c..J .5 >< 0 ~~~ 0 ~sz -ti ~::!!: en ~

19

Log Springs 18 Format1on

? ? ? 17 16s

Cowles Unconform· Member ably overlain 16i by Permian ~ "-' "' c: Rancheria ~·~ 15 u E Manuel· c ; - Formation ~ 0 a: u.. .••d fi·i =i=~- ? ? ? Member .! ~ i :FE 14 ~~~ gL~-...-<~.-..--1 Turqu~lo .; Member 13 ii~ .!f.,_ Macho Member 12 ? ? 11

Las Cruces Formation of Laudon V'l."l'l-.1 .~ll ILA? and Rancheria Bowsher Oooa Ana Formation (1949) ~ ~---~~.!!- ? ~!'. ? ? ] ! ~::~r 8 1------T~erra ~A...J-..1 .1-L-'--V~h.-'--J-.uc.....-_,_ ...__..._, Blanca T11rra Blanca I ., T~erra Blanca ! Member g Member .! 1-- .M"!!!i'!!.- ~ ----·- o; r----- ~ Nunn NuM E Nunn = 7 f---7- ~--~·.!'!b!!.._ :.5 1-:.Mf!!..'b!!._ :.::; 1--.~"!!'fl~­ Alamogordo .!" Alamogordo ! Alamogordo Member ~ Member > Member tC: .:11------._ ro ~ ~Anctr_ecrto_ r-A..-eci;- Q.)·- :! ~ Andrecito "'C ~ Member Member Member c:o -~ ·- 0 ::::t::...c: Caballero Caballero Caballer~~~ Pre-7 ~~~For~~~~~~~~~F-or~~tioo~~~-Fo~rm-at~ioo n nn ...... cha..--.....,WllljJJ IJ IJ J l Rocks I~J..-V..PerJ....L....chaf....LU.-1."'-.J--'Per lll. LlliJ Up~;c~; ~~~r~c~; Ouray beneath Shale Shale Sly Gap Sly Gap Shale Shale limestone Mississippian Formation Formation 1 Upper 'Upper (Upper jUpper (Upper jUpper I 1 jUpper System Devonian) Devonian) Devonian) Devonian) Devonian) Devonian) Precambrian Precambrian Precambrian Precambrian Devonian)

Stratigraphy 5 105" 104"

WESTERN FACIES <

32" <

Symbols explained in figure 1 A < .,., =<= ·-"'-0 :£g~~ < _J < Q) c

~Q) E :.:; < 7-8 .,"'

w~ <

EXPLANATION SEDIMENTARY STRUCTURES

Bird's- eye ---L... Crossbedding Mountains, E Intraclasts Q Vugs 4 Ajax Hills,Tombstone Hills, SE 1,4 sec. 4, T. 23 S., R. 23 E., t:, Chert - Calcite pseudo- SW 1,4 sec. 23, T. 20 S., morphs or gypsum R. 22 E., Arizona Arizona 3 Dry Canyon. FOSSIL PARTICLES Whetstone Mountains, .(11). ~ "r NW',4 sec. 23, T. 19 N., R. 19 E., Stromatolite Fusulinids Echinoderm* Bryozoan ")-.. 00 ~ Sponge spicules Solita,9 coral Colonial carol Broch1opod ROCK TYPES (J» 6 Cal~ous Pele~pod Ostracode Molluscan algae db IJ, fragments Foraminifers Leaves CARBONATE PARTICLES OTHER THAN FOSSILS COATED PARTICLES . Size Mud ONE MORE THAN c:=J ~ la= ~ COAT ONE COAT Sandstone Argillaceous Chert Covered SILT 0 limestone interval SAND '*' -o- 0010 0 0 SUPERFICIAL f&~'R-=l GRANULE ¢1 ~ l===tJ 0010 @ Conglomerate Nodular limestone PEBBLE .. PISOIO Shale ;n shale

Figure 4. Correlation diagram along section line A-A', extending from Vinton Canyon in the Franklin Mountains of western Texas to the Vekol Mountains of Arizona, showing microfacies and microfossil zones in the eastern facies (Las Cruces, Rancheria, and Helms Formations), central facies (Escabrosa Group, Paradise Formation), and western facies (Escabrosa Limestone). Wiggly lines, unconformities; vertical jagged lines, facies changes; oblique arrows, directions of faulting.

6 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico CENTRAL FACIES EASTERN FACIES Pedregosa Basin A'

1 0 Vinton Canyon, Franklin Mountains. 5w~ sec. 67, blk. 82, El Paso County, Texas

(5 c:: en ~ ~ -~ -~ ~ Q) .E ~ 1-en 1-en :I '~ >- >- § 2 en en c..~~· UJ!~ :::; z z~ c: c: )!:;:; ~ "' 2 20 en-~~ 0 ~ z :::; CD z

~ 19 ~ Asteroarchaediscus c: 1--- ~;:- biofacies 18 ~ ~~ - z j 17 u 16s - 161 en - - ~ 0 15 c: - [J. ~ z c:; 14 Bri.msia z <( "' i 0 ::> biofacies CD 1L - a: c.. ~ 13 <( iii Q; u en :::; - iii en 12 ~ r-- 11 r--- 10 METERS - 50 c: 9 Q)"' 40 g> i--- ~ 8 D Big Hatchet Mountains, c'S Columbiapora 30 iii NE ~ sec. 30. R. 15 W .. T. 30 5 .. and ;;; i--- biofacies NE ~ sec. 32, R. 15 W. T. 30 5., 1-- 7 I 20 ~ New Mexico i--- ~ -~ ~ 10 "t).>< u 6 Pedregosa pro-7 Asphaltinella Mountains. ~~ biofacies 0 5E~ sec. 19 5W~ sec. 20 and NE~ sec. 29, T. 2 1 5., R. 30 E., Arizona

Stratigraphy 7 Mountains; and in Arizona, the Pedregosa Mountains, Mule argillaceous and have a yellowish-gray tint. The basal Es­ Mountains, Ajax Hills, Waterman Mountains, and Vekol cabrosa carbonates are of pre-zone 7 and zone 7 age in the Mountains. Pedregosa, Mule, Whetstone, Waterman, and Vekol Moun­ Three main lithologic successions are recognized, forming tains and in the Tombstone and Gunnison Hills. They rest un­ a western facies, a central Pedregosa Basin facies, and an east­ conformably on yellowish-gray to maroon sandstone and em, semi-starved-basin carbonate facies. The most westerly limestone of the Martin Formation (Upper Devonian). The outcrops studied for this report are the Vekol and Waterman Devonian-Mississippian hiatus represents latest Famennian Mountains sections in Arizona on the Papago Indian Reserva­ and earliest Toumaisian time. On the basis of conodont tion. Here, the Escabrosa Limestone disconformably rests on studies, Moore and Barrick (1988) found a substantial hiatus the Devonian Martin Formation and is overlain unconform­ in the Big Hatchet Mountains, encompassing the latest ably by thin beds of Morrowan sandstone and fusulinid lime­ Devonian and most of the Kinderhookian, at the base of the stone. The Escabrosa Limestone sections in the Vekol and oolitic limestone. Waterman Mountains are thin in comparison with the Es­ cabrosa Limestone to the east in the Mule or Whetstone Moun­ tains. UNITS OVERLYING THE MISSISSIPPIAN In southeastern Arizona and southwestern New Mexico, Transgressive Pennsylvanian basal quartz-pebble con­ the boundary of the Pedregosa Basin delineates an important glomerate and quartz sandstone, succeeded by shale and fos­ facies change within Mississippian carbonates. The major dif­ siliferous, oolitic limestone, were deposited above the Late ferences are that the Escabrosa Limestone west of the Ped­ Mississippian erosional surface and unconformity. This rela­ regosa Basin contains, in zones 7 and 8, an Asphaltinella and tion is observed throughout southwestern New Mexico and Columbiapora calcareous-algae biofacies which is absent in southeastern Arizona. Pennsylvanian strata in southeastern the Keating Formation of the Escabrosa Group. Furthermore, Arizona truncate progressively older, Mississippian sedimen­ the dark-gray, silty-chert, spiculitic Witch Member of the tary rocks to the west. In the Pedregosa Mountains, the Keating Formation of the Escabrosa Group is not recognized youngest beds are Chesterian, whereas in the Vekol Mountains west of the Pedregosa Basin. Massive encrinite of the Hachita they are Osagean (figs. 3-4). In the Big Hatchet Mountains Formation is also represented in Meramecian encrinite of the of southwestern New Mexico, the hiatus between the Missis­ Escabrosa Limestone in the Mule Mountains of southeastern sippian and Pennsylvanian Systems represents small parts of Arizona. In the Pedregosa Basin, the Escabrosa Group rests zones 19 and 20. Elsewhere in the Pedregosa Basin, in the on the Upper Devonian Percha Shale and is overlain by the Klondike Hills of southwestern New Mexico, at Blue Moun­ upper Meramecian (fig. 3) and Chesterian Paradise Formation. tain in the Chiricahua Mountains, and in the Pedregosa Moun­ Farther east, the Escabrosa Group and Paradise Formation tains of southeastern Arizona, the hiatus between the two grade laterally into the Mississippian Las Cruces, Rancheria, systems represents the upper part of zone 18 (Chesterian), all and Helms Formations. In the Franklin Mountains, the Las of zone 19 (Chesterian), and the lower part of zone 20 (Mor­ Cruces Formation rests on the Upper Devonian Percha Shale rowan). In the Florida Mountains, carbonate slope sedimen­ and is overlain by the Rancheria and Helms Formations, tary rocks of the Mississippian Rancheria Formation are which, in tum, are overlain unconformably by Pennsylvanian unconformably overlain by carbonate rocks of the Hueco For­ fossiliferous limestone of the Magdalena Group. mation (Wolfcampian and Leonardian). This relation and large hiatus reflect the Pennsylvanian Florida uplift (Kot­ LOWER BOUNDARY OF THE MISSISSIPPIAN tlowski, 1960, 1963). To the west, in the Waterman and Vekol Mountains on the Papago Indian Reservation, the Mississip­ In southwestern New Mexico, pre-zone 7 beds of the Bugle pian Escabrosa Limestone is Toumaisian in age and is over­ Member of the Keating Formation unconformably overlie the lain by Lower Pennsylvanian carbonates. Box Member of the Percha Shale (Famennian, Upper De­ At the top of the Gunnison Hills section, a thick regolith is vonian). This relation is observed in the Klondike Hills, Big developed on the Escabrosa Limestone. The Mississippian Hatchet Mountains, and Peloncillo Mountains. To the north, limestone surface has solution holes filled with red-maroon in central New Mexico, the shallow-water, cratonic Caballero clay and silt and reworked cobbles of fossiliferous Mississip­ and Lake Valley Formations have a similar depositional rela­ pian limestone and chert. Rounded and reworked Merame­ tion to the Percha Shale. In the Pedregosa Basin, it is difficult cian rugose colonial corals assigned to Acrocyathus? shimeri to recognize the hiatus and contact between the Devonian and (Crickmay) are associated with the cobbles. the Mississippian on the basis of lithologic characteristics. The Whetstone Mountains section also shows evidence of The highest Devonian beds are argillaceous, commonly fos­ extensive pre-Pennsylvanian solution activity. The top of the siliferous limestone that does not differ lithologically from the Mississippian limestone is an irregular surface marked by basal Mississippian beds. The Devonian limestone beds are cavities and solution holes filled by a dark-maroon "Terra generally thinner and contain more shale interbeds, or are more Rossa" shale. These solution features extend some 2 to 3 m

8 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico downward into the Escabrosa Limestone. The basal Pennsyl­ the Bugle Member are chert-free, arenaceous, oolitic grain­ vanian is a thick (2m) bed of brown pebble conglomerate com­ stone. Dolomite is rare in the Bugle Member except in the J,osed of chert derived from the Escabrosa Limestone. Pedregosa Mountains section, where 40 m of gray dolomite succeeds the basal oolites. Sedimentary structures in the dol­ omite include algal mats, fenestrate structures, bird's-eyes, and possible spar-dolomite pseudomorphs after evaporites. In ESCABROSA GROUP the Big Hatchet Mountains, the basal beds are oolitic grain­ stone and bryozoan-echinoderm packstone (Moore and Bar­ The Escabrosa Limestone in the eastern Chiricahua Moun­ rick, 1988). The upper half of the Bugle Member is tlins was elevated to group rank by Armstrong (1962), who thin-bedded, argillaceous and arenaceous, fossiliferous C.ivided it into two named formations: the Keating Formation wackestone and packstone. Younger beds contain a distinctive and the overlying Hachita Formation (figs. 5, 6). Armstrong and diagnostic coral fauna that is commonly preserved by and Mamet (1978b) formally named the two informal mem­ brown chert on the surface of the limestone. This coral fauna t ·ers of the Keating Formation the Bugle and Witch Members. includes Stelechophyllummicrostylum (White), S.lochmanae (Armstrong), and Rylstonia cf. R. teres (Girty). The faunal diversity and the oolitic to bryozoan-echinoderm packstone Keating Formation and wackestone suggest subtidal to shoaling environments of deposition. Sedimentary structures in the dolomites of the E.ugle Member Pedregosa Mountains indicate that parts of the Bugle Member The Bugle Member of the Keating is 29 m thick in the Klon­ were deposited in an intertidal environment. dike Hills and 98 m thick in the Pedregosa Mountains. It rests The lower, pre-zone 7 beds in the Escabrosa Limestone in with disconformity on calcareous shale and limestone of the southeastern Arizona are a westward facies of the Bugle Mem­ I'ercha Shale. In the Pedregosa Mountains, the basal beds of ber. These dolomitic lime mudstone and dolomite contain

Figure 5. Northeast side of the Boss Ranch section, Pedregosa Mountains, Ariz. Arrows denote part of measured section. The Paradise Formation is exposed over west side of high ridge in a valley. Om, Devonian Martin Formation; Mk, Lower Mississippian Keating Formation; Mh, Lower and Upper Mississippian Hachita Formation.

Escabrosa Croup 9 laminated algal mats and bird's-eye structures, suggesting an tween the Bugle and Witch Members is gradational over a intertidal to supratidal environment of deposition. In south­ stratigraphic thickness of 1 to 2m; the contact is placed at the central New Mexico, the Caballero Formation and the An­ change in lithology from gray chert-free limestone of the drecito Member of the Lake Valley Formation are a Bugle Member to dark-gray limestone and nodular chert of the northeastward subtidal facies of the Bugle Member. Witch Member. The lower beds of the Witch Member, 0.2 to The Bugle Member comprises a series of incomplete shoal­ 0.3 m thick, are peloid-bryozoan-echinoderm wackestone and ing-upward shelf or platform cycles formed by crinoid­ packstone. Arenaceous, spiculitic lime mudstone and bryozoan sand, succeeded by oolitic shoals with restricted arenaceous, well-sorted peloid-bioclastic packstone are the communities of rugose and tabulate corals associated with common rock types in the upper part of the member. Quartz oolitic packstone, and capped by lime mudstone and dolomite sand grains, 100 j..tm in size, constitute 5 to 10 percent to the of supratidal origin. These rock types and shoaling-upward rock. Thin-section studies reveal that the nodular chert preser­ cycles are best displayed in the Pedregosa Mountains. ves in silica the relic texture of the replaced carbonate rock. The Witch Member contains a zone 7 microfossil assemblage; Witch Member the most characteristic megafossil is the brachiopod Imbrexia The Witch Member ofthe Keating Formation is 62 m thick forbesi (Norwood and Pratten). The dark color of the organic- in the Pedregosa Mountains, 81 m thick in the Big Hatchet rich limestone and chert, the presence of arenaceous spiculitic Mountains, and 175m thick in the Klondike Hills. The Witch and peloidal microfacies, and the abundance of chert suggest Member is a dark-gray, medium-bedded limestone containing that the Witch Member was deposited on the outer shelf in a abundant dark-brown to black nodular chert (fig. 7); chert deeper-water environment. Within the Pedregosa Basin, the nodules form 30 to 50 percent of the rock. The contact be- sedimentary rocks of the Witch Member indicate that they

Figure 6. Escabrosa Group on north side of Blue Mountain in the Chiricahua Mountains, Ariz. Dm, Devonian Martin Formation; Mh, Lower and Upper Mississippian Hachita Formation; Mkb, Bugle Member of the Mississipp ian Keating Formation; Mkw, Witch Member of the Keating Formation; Mp, Upper Mississippian Paradise Formation; IPh, Pennsylvanian Horquilla Limestone. Type section of the Paradise Formation is on this hill, where exposures are excellent.

10 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico were deposited in a shallow-water cratonic basin, as a car­ the Pedregosa Mountains (fig. 7), 80 m thick in the Klondike bonate slope facies, in a semistarved environment, at water Hills, and 48 m thick at Blue Mountain in the Chiricahua depths possibly greater than 30m (Wilson, 1975a; Mullins, Mountains (fig. 8). The Hachita Formation has a sharp con­ 1986). tact with underlying dark-gray cherty limestone of the Witch Member of the Keating Formation (fig. 8). The Hachita is composed of light-gray, massive, poorly bedded, bryozoan­ echinoderm packstone to grainstone and contains light-gray Hachita Formation nodular chert. In thin section, the rock is composed of poorly sorted crinoid and bryozoan bioclasts, with a micritic or spar­ The type section for the Hachita Formation of the Es­ ry-calcite matrix. Some beds contain brachiopod bioclasts, cabrosa Group is in the Big Hatchet Mountains (Armstrong, but the predominant fossil remains are echinoderms. 1962), where the formation is 90 m thick. It is 140m thick in Foraminifers and calcareous algae are very rare in this facies.

Figure 7. Typical dark-gray chert of the Witch Member of the Keating Formation in the Blue Mountain section, Chiricahua Moun­ tains, Ariz., showing abundance of lenticular chert in a matrix of gray, silty, peloid-echinoderm-spiculitic packstone.

Hachita Formation 11 The lithology of the Hachita Formation remains constant the age of the base of the formation, conodont samples were throughout its area of outcrops. Paleontologic zonation ofthe collected from the base of the section in the Pedregosa Moun­ Hachita Formation is difficult owing to the absence of recog­ tains. In these samples, J .E. Repetski (written commun., 1979) nizable megafossils and microfossils. In an effort to determine identified the following conodonts:

Figure 8. Contact between the Witch Member of the Keating Formation and the Hachita Formation. Underlying Witch Member is dark-gray lenticular chert in a matrix of well-sorted crinoid-peloidal packstone; overlying Hachita Formation is I ighter gray, coar­ ser grained, crinoidal packstone-grainstone that is devoid of dark-gray lenticular chert.

12 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico Bispathodus? spp. (B. stabilis type, fragment) 1 PARADISE FORMATION Polygnathus communis communis Branson & Mehl 3 Spathognathodontiform element (fragment) 1 Stoyanow ( 1926) named the Paradise Formation (late Mer­ Igonodiniform (A2) elements 3 amecian and Chesterian), for outcrops near the old mining Onchodiniform (A2) element 1 camp of Paradise in the Chiricahua Mountains of Arizona. Platform element, robust form (fragment) 1 The Paradise Formation is limited to the Pedregosa Basin of southeastern Arizona, southwestern New Mexico, and northwestern Chihuahua, Mexico. Repetski stated: The base of the Paradise Formation is defined at the change Because the rocks that immediately underlie these samples are Osagean, then from massive echinoderm-bryozoan packstone at the top of these sample are also Osagean. Polygnathus commun.is ranges only through the Hachita Formation to olive-gray, thin- to medium-bedded, the lower two-thirds of this series. Nothing in this faunule indicates a con­ ooidal, argillaceous-arenaceous limestone of the Paradise For­ siderable hiatus. The conodont-alteration index (CAl) of these specimens is mation. Hernon (1935, p. 658) explained this change as due about 4, indicating minimum host-rock temperatures of about 140 to 215 "C. to the shallowing of waters of Escabrosa sedimentation * * * The conodonts suggest that sedimentation may have continued across "* * * the Keating-Hachita boundary, and possibly no hiatus exists between the two and the introduction of terrigenous clastic sedimentation formations. If a hiatus does exist, it represents less time than indicated by the during Paradise time." In the Big Hatchet Mountains section, Armstrong and Mamet (1978b) regional correlation chart for the Escabrosa at 4 m above the base of the Paradise Formation, a cephalopod Group. It spans a relatively short time interval within the Osagean. fauna was identified by MacKenzie Gordon, Jr. (written com­ mun., 1973), at USGS locality 25052-PC:

Repetski found a similar age relation between the Keating Brachycycloceras spp. and Hachita Formations in the Peloncillo Mountains of New Girtyoceras spp. Mexico. Goniatites americanus Gordon Megafossils found in the lower two-thirds of the Hachita Miche/inoceras? spp. Formation in the Big Hatchet Mountains and at Blue Mountain Mitorthoceras perfilosum ?Gordon in the Chiricahua Mountains include Brachythyris subcardii­ Reticycloceras spp. formis (Hall) and a few specimens of the coral Amplexi­ zaphrentis spp. The upper 20 to 30 m of the formation yielded Gordon stated: a fauna of the brachiopods Werriea keokuk (Hall), and Syrin­ gothyris subcuspidatus (Hall). This assemblage indicates an The cephalopods are fairly well preserved. The nautiloids have never been early Visean (early Meramecian) age. Microfossil studies worked out for this zone, so I have hesitated to apply specific names on this (fig. 10) indicate that a hiatus which spans zones 12 and 13 is little material. The Mitorthoceras has the same surface sculpture as M. per­ present within the Hachita Formation (fig. 4). filosum, but I have not seen the internal structure. The G irtyoceras is the same species that we find in this zone in the Confusion Range, Utah, but is not The Tierra Blanca Member of the Lake Valley Formation described. The Goniatites americanus zone is the lowest of three zones is an eastward, echinoderm-bioclastic, carbonate-sand facies characterized by species of Goniatites and marks the top of the Meramecian of the Hachita Formation of the Escabrosa Group. To the west, series in the Midcontinental and Western United States. It should occur with the upper part of encrinite of the Escabrosa Limestone at Dos zone 15 foraminifers. Cabezas and in the Mule Mountains, Tombstone Hills, and Whetstone Mountains of Arizona is also a lateral, echinoderm­ A foraminiferal fauna of zone 15 does, indeed, occur with bioclastic, carbonate-sand facies of the Hachita Formation. the cephalopods. The late Visean foraminiferal "Brunsia biofacies," which The thickest and most complete sections of the Paradise corresponds to zones 14 and 15 (late Meramecian), has been Formation are in outcrops in the Big Hatchet Mountains of recognized in the upper part of the Hachita Formation. The New Mexico. Here, the Paradise Formation is 133 m thick and abundance of crinoid-bioclastic grainstone and packstone, consists of gray through dusty-yellow-gray to dusty-greenish­ with minor oolitic grainstone, indicates that the sediment was gray limestone alternating with thin-bedded calcareous shale, deposited as crossbedded sand in shoaling water. This siltstone, and sandstone. The carbonate rocks are typically crinoidal facies was deposited on a broad, regional shallow lime mudstone, brachiopod-bryozoan-molluscan wackestone platform that extended over a large area of southern New and packstone, and crossbedded ooid-foraminiferal packstone Mexico and southern Arizona. This massive crinoidallime­ to grainstone, in beds 0.5 to 2m thick. stone or encrinite is common in rocks of this age in the Cor­ The type section of the Paradise Formation at Blue Moun­ dilleran miogeosyncline of North America from Arctic Alaska tain is 48 m thick (fig. 6). The base of the Paradise is charac­ to central Mexico (Mamet, 1976; Armstrong and Mamet, terized by thin-bedded (0.3-0.9 m thick), arenaceous, 1977; Mamet and others, 1986). peloid-crinoidal packstone that overlies light-gray, massive

Paradise Formation 13 echinoderm-bryozoan packstone of the Hachita Formation. of quartz sandstone. The overlying Horquilla carbonate strata Hernon (1935) found 155 fossil taxa in the Paradise Forma­ are massive brachiopod-echinoderm-coral-foraminiferal tion and described and illustrated many genera and species of wackestone to packstone. Zeller (1965) collected fossil plants megafossils. He divided the Paradise Formation into eight in­ in the 1-m-thick sandstone bed that overlies the Paradise For­ formal members and gave the stratigraphic ranges of the mation; these fossils were identified by C.B. Read (in Zeller, megafossils. Hernon found the faunas to be well zoned and 1965, p. 29) as Lepidodendron obovatum Sternberg. Read indicated that the formation is correlated with the St. Louis(?) commented, "Lepidodendron obovatum is very common in the through Ste. Genevieve Limestones (Meramecian) and the Early Pennsylvanian and is not found in rocks of Chesterian lower and middle Chesterian of the Mississippi Valley. The age." The sandstone and the massive overlying Horquilla lower 25 m of the Paradise Formation is characterized by 0.3- Limestone indicate both a lithostratigraphic change in sedi­ to 1-m-thick beds of ooidal packstone to grainstone, peloid­ mentation and a biostratigraphic break. Armstrong and echinoderm wackestone and packstone with gray calcareous others' (1984) conodonts obtained from the section indicate a shale interbeds, and nodular calcareous lime mudstone. Sub­ short hiatus between the Mississippian and Pennsylvanian. rounded grains of 50- to 100-J..Ull quartz sand are common. TheRhachistognathus-zone fauna established by Dunn (1970) Platy, brownish-yellow-weathering, argillaceous quartz sand­ in Nevada and Utah is absent here. Diagnostic conodont ele­ stone is found from 25 to 32m above the base; the quartz grains ments extracted from the basal part of the Horquilla Limestone are angular and range in size from 75 to 125 J..Lm. Above these include: Gnathodus bass/eri symmetricus Lane, G. bassleri arenaceous beds are 7 m of 10- to 30-cm-thick beds of bass/eri (Harris and Hollingsworth), and Declinognathodus foraminifer-brachiopod-crinoidal to ooid-peloidal packstone. noduliferus (Ellison and Graves). The Paradise Formation Interbedded are thin (5-30 em thick) beds of light-olive-green yields Gnathodus girtyi simplex Dunn, which represents the to yellow-gray calcareous shale and quartz sandstone. The top youngest Mississippian faunal zone established by Dunn 10 to 12m of the Paradise Formation is composed of light­ (1970). olive-gray to brown, argillaceous, fossil-leaf-bearing sand­ The Paradise Formation of the Pedregosa Mountains is stone. A 1-m-thick, ooid-brachiopod-Archimedes wacke­ similar in lithology to the Big Hatchet Mountains outcrops. stone is interbedded in the sandstone 4 m below the Paradise­ The 87-m-thick section contains, in its basal beds, calcareous Horquilla contact. The poorly exposed, plant-bearing quartz sandstone and rounded-chert-pebble conglomerate in quartzose sandstone at the top of the Paradise Formation con­ beds 1 m thick. The uppermost 20 m of the Paradise Forma­ tains abundant hematite and argillaceous partings. Thus, the tion is peloidal to ooid-foraminiferal packstone and grainstone contact between the Chesterian part of the Paradise Formation that yielded a zone 18 microfossil assemblage. The overlying and the Morrowan part of the Horquilla Limestone is poorly Pennsylvanian part of the Horquilla Limestone is foraminifer­ exposed. ooidal grainstone containing a Morrowan zone 20 microfossil The hiatus between the two systems at Blue Mountain, as assemblage. No sandstone, shale, or terrigenous clastic beds indicated by foraminifers and calcareous algae, represents a occur between the two systems. At the top of the Paradise For­ part of zone 18 and all of zone 19 (Chesterian) time (fig. 9). mation is an olive-gray ooidal grainstone that is overlain by a The basal peloid-ooidal wackestone and packstone of the Hor­ gray, nodular-chert, tabulate-coraVooidal grainstone. Micro­ quilla Limestone contain a rich microfossil assemblage of fossil determinations show that the hiatus between the Mis­ zone 20 (Morrowan, Pennsylvanian) age (fig. 9). Foram­ sissippian and Pennsylvanian Systems in the Pedregosa inifers from the type section of the Paradise Formation indi­ Mountains represents part of zone 18 and all of zone 19 cate a similar hiatus. Horquilla Limestone conodonts at Blue (Chesterian) time. Burton identified the conodonts Cavus­ Mountain include: Adetognathus lautus (Gunnell), A. gigan­ gnathus Harris and Hollingsworth, Streptognathodus Stauffer tus (Gunnell), and Streptognathodus parvus Dunn. The pres­ and Plummer, andNeoprioniodus Rhodes and Miller, indicat­ ence of S. parvus indicates that part of the Horquilla Limestone ing a latest Chesterian age for the upper part of the Paradise is equivalent to the middle Morrowan or the upper (G 1) Formation. Basal beds of the overlying Horquilla Limestone Gastrioceras goniatite zone. Cavusgnathus unicornis Young­ yield Adetognathus lautus (Gunnell) and A. gigantus (Gun­ quist and Miller, Gnathodus bilineatus (Roundy), and Lam­ nell), which, in the absence of the zone indicator Rhachisto­ bdagnathus Rexroad indicate a middle late Chesterian age or gnathus, suggest an early Morrowan age. lower Eumorphoceras zone for the underlying Paradise For­ The Paradise Formation section in the Klondike Hills of mation. New Mexico is 63 m thick and contains the "Brunsia bio­ The Paradise Formation in the Big Hatchet Mountains con­ facies" in its basal beds. Microfossils of zone 16i are found 5 tains all the Chesterian microfossil zones from zones 16 m above the base. The upper 6 m of the section is a through 19 (fig. 9). Zone 19 isknownonlyin the Paradise For­ crossbedded ooid-foraminiferal packstone and grainstone mation of the Big Hatchet Mountains, where Quasiarchaedis­ containing zone 18 microfossils. The basal Pennsylvanian is cus spp. is found. The contact between the top of the Paradise a light-brown, hematitic, massive 6-m-thick bed of Lepido­ Formation and the Horquilla Limestone is a 1-m-thick layer dendron-bearing, crossbedded quartz sandstone. This bed is

14 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedragosa Basin, Arizona and New Mexico overlain by peloid-echinoderm-foraminiferal packstone con­ Formation was deposited in shallow to shoaling environments taining zone 20 (Morrowan) foraminifers. with abundant foraminifers, brachiopods, crinoids, bryozoans, The hiatus in the Klondike Hills, as indicated by and mollusks. The terrigenous clastic material represents in­ foraminifers and calcareous algae, represents part of zone 18 fluxes of clay and quartz sand, possibly derived from rising and all of zone 19 (Chesterian). The youngest conodont fauna positive areas to the west and north (fig. 2). derived from the Paradise Formation in the Klondike Hills contains Gnathodus texanus Roundy, G. commutatus (Bran­ son and Mehl),Neoprioniodus loxus Rexroad, and Hibbardel­ WESTERN FACIES OF THE ESCABROSA la milleri Rexroad. This fauna indicates the lower part of the LIMESTONE upper Chesterian, or lower Eumorphoceras goniatite, zone. The oldest Pennsylvanian conodont element present is Adeto­ The Escabrosa Limestone includes the Mississippian strata gnathus lautus (Gunnell), which, in the absence of Rhachis­ from the west side of the Chiricahua Mountains westward to tognathus, indicates a lower Morrowan age. The Paradise the Vekol Mountains and northward to the Mogollon Rim in

Q) CJ) Q) Q) c c 1- 0 0 N Q) c N E CJ) C'O Q) Q) ...... CJ) ...... C'O Q. CJ) CJ) c () 0 0 0 > c 1- "0 (/) ::J ,_0 ·::;: L.U 0 -() 0 c 1- 0.... 8 ~

(l)­ c co c C'O Declino- 21 = 0 ·~ gnathodus ____ g.Rjo~ .:::1:. o E as e ..c noduliferus I~Z~ CJ) C'O c::o 20

c C'O ·~-:;::- ::J I.- e E ~ co co- ·~ ~~K~la_d_o---r----~ c Z c Q c 0 co t) gnathus 1 7 0 ·~ ~ E c z OJ C. naviculus co E 0 0 r----~~~==~---­ u.. ·~ <( ..c E 0 co u 0 u.. u.. (l) E Cl: (/) (l) 0 a... (/) u.. (l) '6 (/) co (/) '6 (l) (/) '6 ~ ~ (/) ~ co '6 co Cl.. co (/) Cl.. (/) ~

~ r----- c -7-7-­ C'O r------7--7- Q) c CJ) C'O () > Q) E C'O 1- Q) ~ 13

Figure 9. Time-stratigraphic chart for the Paradise Formation, showing extent of hiatus between the Mississippian and Pennsylvanian Systems in the Pedregosa Basin (after Armstrong and others, 1984).

Paradise Formation 15 Arizona. G .H. Girty' s (in Ransome, 1904) type section for the Rancheria and Upper Mississippian Helms Formations. Pray Escabrosa Limestone is in the Mule Mountains, south of Bis­ (1958) made a petrographic and microfacies analysis ofWaul­ bee, Ariz. (Hayes and Landis, 1965), where it is 218m thick; sortian bioherms of the Lake Valley Formation in the Sacra­ it thins to the west and is 100m thick in the Vekol Mountains. mento and San Andres Mountains. The Escabrosa Limestone unconformably overlies shale, are­ Wilson (1969, 1971, 1975b) and Kottlowski (1970, 1975) naceous limestone, and dolomite of the Devonian Martin For­ described the complex tectonic events that resulted in deposi­ mation. tion of the Lower and Upper Mississippian Rancheria and Basal beds of the Escabrosa Limestone are typically bryo­ Upper Mississippian Helms Formation over eroded Lower zoan-echinoderm wackestone and packstone. In the Gunnison Mississippian shelf carbonates of the Lake Valley Limestone and Ajax Hills, they contain a pre-zone 7 microfossil as­ in south-central New Mexico and western Texas. Meyers semblage; elsewhere, the oldest recognized microfossil as­ (1974, 1975) and Meyers and James (1978) deciphered the semblages are zone 7 or 8. As shown in figure 4, correlation complex geologic history of the Mississippian carbonates and between outcrops by lithologic characteristics is difficult their diagenesis in the Sacramento Mountains from petrog­ owing to rapid lateral facies changes. Correlations based on raphic, stable-isotope, and cathodoluminescence studies. the abundance of chert or carbonate microfacies are not sup­ Meyers demonstrated that the nonferroan calcite-cement ported by microfossil-assemblage zones. Lithologic correla­ zones in the Lake Valley Limestone reflect ancient phreatic tions that prove reliable in the Escabrosa Group do not carry lenses established during pre-Visean (pre-Meramecian) and westward into the thinner Escabrosa Limestone. The Es­ pre-Bashkirian (pre-Morrowan) periods when meteoric waters cabrosa Limestone thins westward and northward to the Mo­ cemented these rocks below unconformities. gollon Rim (McKee and Gutschick, 1969, fig. 2), owing not Investigations of the basin-margin sedimentary rocks of the only to depositional thinning but also to pre-Pennsylvanian Visean (Meramecian and Chesterian) Rancheria Formation in erosion that removed the younger beds. The Escabrosa Lime­ the Sacramento and Franklin Mountains by Yurewicz (1973, stone at Superior, Ariz., is 188m thick and ranges in age from 1977) showed that the Rancheria Formation postdates the pre-zone 7 to zones 9/10. The Gunnison Hills section has a Lake Valley Limestone and is separated from it by an uncon­ similar age range but is 239 m thick (Armstrong and Mamet, formity. Yurewicz (1977) found that intraformational ero­ 1978b; Armstrong and others, 1980). The Escabrosa Lime­ sional surfaces, interpreted as submarine features, are present stone thins and becomes more dolomitic westward from the locally within the Rancheria Formation; they are most sig­ Whetstone Mountains to the Waterman and Vekol Mountains. nificant along the basin margin in the Sacramento Mountains. The Vekol Mountains section contains well-developed algal The rarity of slumping in the Rancheria Formation indicates a mats, stromatolites, mud chips, mud cracks, and fenestrate relatively stable basin floor. A deep-water origin for most of sedimentary structures in its upper half, indicating intertidal to the Rancheria Formation is suggested by its dark color, the supratidal environments of carbonate deposition, according to predominance of mud- and silt-size sedimentary material, its the criteria of Hardie (1977) and Hardie and Shinn (1986). very low faunal density, the absence of wave- and surf-formed The Escabrosa Limestone in southeastern Arizona repre­ structures, the absence of typical shallow-water features, the sents a marine transgression over an eroded Devonian surface, amount of relief along the basin margin, and its similarity to and development of a shallow carbonate shelf with subtidal to other known deep-water carbonates. supratidal environments during the Early Mississippian. Ter­ Study of the conodont faunas of the Lake Valley Lime­ rigenous clastic materials are generally absent, and typical stone, Rancheria Formation, and Helms Formation by Lane sedimentary rocks are lime mudstone, dolomite, peloidal (1974, 1975) (fig. 6) conclusively demonstrated that the wackestone-packstone, crinoid-brachiopod wackestone­ Visean Rancheria Formation in the Franklin Mountains of packstone, and ooid-oolitic packstone-grainstone. western Texas and in the southern San Andres and Sacramen­ to Mountains of New Mexico has a wedge-on-wedge relation to, separated by an unconformity from, upper Tournaisian RANCHERIA FORMATION (Osagean) shelf carbonates and bioherms of the Lake Valley Formation. The fauna and lithology of the Mississippian carbonate Conodont samples were collected with the foraminiferal rocks in the San Andres and Sacramento Mountains of south­ samples from the Florida Mountains section of the Rancheria central New Mexico have been well described. The first Formation. Foraminifers of the zone 14/15 Meramecian detailed studies of the Mississippian of this area were by "Brunsia biofacies" were found from 12 m above the base to Laudon and Bowsher (1941, 1949) on the stratigraphy and the top of the section beneath Wolfcampian limestone. J.E. megafaunas of the Mississippian Caballero and Lake Valley Repetski (written commun., 1979) found Meramecian con­ Formations and on bioherms of the Lake Valley Formation. odonts within the "Brunsia biofacies" and reported the follow­ They described the wedge-on-wedge relations of these Lower ing conodonts in a sample from 1.5 m above the base of the Mississippian strata to the Lower and Upper Mississippian Rancheria section:

16 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico Gnathodus spp. (juvenile?) 1 SUMMARY OF THE LITHOLOGIES OF THE Polygnathus communis Branson and Mehl 4 THREE REGIONAL FACIES Spathognathodus cf. S. cristulus Youngquist and Miller 6 Spathognathodus spp. 1 Lithologies of the Western Facies Ozarkodiniform element 1 Neoprioniodiform (N) elements 2 The relatively thin sections of the Escabrosa Limestone in Synprioniodiniform (N) elements 2 the Vekol and Waterman Mountains were deeply eroded Hindeodelliform (AI) elements 11 before Pennsylvanian deposition. The strata are dominately Ligonodiniform (A2) element 1 dolomite, with well-developed intertidal and supratidal sedi­ Hibbardelliform (A3) elements 4 mentary structures. In these outcrops, the diagnostic microfossils and carbonate rock types are columbiaporid-algal Repetski stated, "The age is Mississippian, probably grainstone containing Asphaltinella and Syringopora corals. Osagean." Polygnathus communis has a known range from In the Whetstone Mountains, Ajax Hills, Tombstone Hills, and the upper two-thirds of the Famennian (Upper Devonian) Mule Mountains of Arizona, the Escabrosa Limestone is com­ through the lower half of the Osagean. Burton (1964, p. 75) posed mainly of algal-rich lime mud, peloidal grainstone, and reported finding P. communis throughout the Rancheria For­ associated crinoid-bryozoan packstone and grainstone. The mation in the southern Sacramento Mountains of New upper part of the section is formed by crinoid-bryozoan pack­ Mexico, and he referred the Rancheria Formation to the stone and grainstone. Meramecian. Elsewhere (p. 73), however, he stated that the faunas from the Rancheria Formation "* * * are small and reworked and thus are oflimited stratigraphic value." The ap­ Lithologies of the Central Facies parent absence of abrasion in specimens from the Florida Mountains (sample 72N-5+4) suggests that the Rancheria The Boss Ranch section is one of the best exposures of the Formation is a highly condensed sequence. This thin ( 1.3 m Escabrosa Group in the Pedregosa Mountains and Pedregosa thick) unit, of probable Osagean age, is here assigned on Basin. Here, the Bugle Member of the Keating Formation is, lithologic evidence to the Rancheria Formation. in part, light-gray, coarsely crystalline dolomite. The J.E. Repetski (written commun., 1979) recovered the fol­ dolomite contains well-developed stromatolites, rip-up clasts, lowing conodonts in a sample from 3 m above the base of the spar-dolomite pseudomorphs after anhydrite, and laminated Rancheria Formation in the Florida Mountains: algal mats; all these features indicate intertidal to supratidal environments of deposition. The upper part of the member Cavusgnathus spp. 4 contains peloid-crinoidal wackestone and packstone. Some Gnathodus texanus Roundy 38 beds contain varying amounts of subrounded, silt- and sand­ Gnathodus spp. (fragments) 3 size quartz grains in a calcite matrix. Silicified solitary and Spathognathodus spp. (fragment) 1 colonial rugose corals are abundant in the higher beds. Ligonodiniform (A2) elements 10 The Witch Member of the Keating Formation contains Lonchodiniform elements 7 abundant dark-gray nodular chert in an arenaceous, peloid­ Neoprioniodiform element 1 spiculitic lime mudstone to peloidal packstone. The top of the Witch Member, deposited in shallow water with an abundant Repetski reported the age to be Meramecian and stated: foraminiferal fauna, is composed of black nodular chert, peloid-spiculitic grainstone, and packstone; some silt-size Cavusgnathus first appears in the Meramecian and ranges into the Chesterian. quartz is also present. Field evidence suggests a paraconform­ Gnathodus te.xanus ranges from the upper Osagean into the lower Chesterian. ity at the top of the Witch Member. The Cavusgnathus specimens are broken, as are the specimens of Gnathodus The Hachita Formation is a massive, poorly bedded, spp. The latter have widely expanded outer lobes, similar to G. bi/ineatus (Roundy). The G. te.xanus collection shows a wide variation in platform or­ crinoidal packstone containing minor amounts of light-gray namentation. nodular chert; some beds contain abundant bryozoan frag­ ments. The lower and middle parts of massive encrinite of the The Visean (zones 13-16, Meramecian and Chesterian) Hachita Formation contain no diagnostic foraminifers, but the Rancheria and Visean and Namurian (zones 16-19, Ches­ partially oolitic upper part of the formation contains terian) Helms Formations of western Texas and in the Sacra­ foraminifers and brachiopods of late Visean age. mento and San Andres Mountains of New Mexico, and the The Paradise Formation, upper Visean to lower Namurian truncated outcrops of the Rancheria Formation in the Florida (upper Meramecian to upper Chesterian), comprises a cyclic Mountains of New Mexico, also appear to have a wedge-on­ succession of very shallow water sedimentary rocks, consist­ wedge relation and are separated from the Toumaisian Keat­ ing of medium-bedded siltstone, mudstone, shale, lime mud­ ing Formation by a post-zone 9, pre-zone 14 unconformity. stone, bryozoan packstone, oolites, coral- and brachiopod-rich

Summary of the Lithologies of the Three Regional Facies 17 carbonates, and nearshore sandstone containing abundant Pre-zone 7 foraminifers are absent above the Devonian plant remains. Martin Formation in the Mule Mountains, Whetstone Moun­ tains, Ajax Hills, and Tombstone Hills outcrops. The Missis­ sippian carbonates above the Devonian unconformity are Lithologies of the Eastern Facies peloidal wackestone and packstone containing late Tour­ naisian and early Visean microfossils. Stratigraphically The Mississippian Las Cruces Formation (Laudon and higher in these outcrops, possible hiatus and noncontinuity of Bowsher, 1949) is a dark-gray, carbonaceous-argillaceous­ microfossil zones make it impossible to determine how much siliceous, spiculitic wackestone to lime mudstone. It is over­ of the Visean (in part, Meramecian) may be represented. In lain by the Rancheria Formation (Laudon and Bowsher, 1949, the Ajax Hills, Tombstone Hills, and Mule Mountains, the Yurewicz, 1977), which consists of lime mudstone, spiculitic youngest part of the Escabrosa Limestone contains the late wackestone, quartz-silt-pellet grainstone, and packstone. The Visean "Brunsia biofacies" (zones 14-15) of the southern rocks contain abundant brown to gray nodular chert. Arizona western facies. The contact between the Rancheria Formation and Helms In the Klondike Hills and Big Hatchet Mountains of New Formation was considered by Laudon and Bowsher (1949) to Mexico, the Bugle Member of the Keating Formation rests dis­ be an unconformity. The Helms Formation consists of yel­ conformably on Upper Devonian (Famennian) marine sedi­ lowish-gray, thin-bedded lime mudstone, dolomite, and mentary rocks of the Box Member of the Percha Shale. The greenish-gray to gray shale. The Helms Formation is uncon­ Bugle Member is Kinderhookian (pre-zone 7) in age, on the formably overlain by highly fossiliferous wackestone and basis of foraminifers. It contains a rich rugose-coral fauna, shale of Morrowan (zone 20, Pennsylvanian) age. typified by Stelechophyllum microstylum (White) (Arm­ strong, 1962). Sando and Bamber (1985) reported this coral to be common in upper Kinderhookian strata of the Canadian MICROFOSSILS, FORAMINIFERS, AND and U.S. Cordilleran province. CALCAREOUS ALGAE Middle Tournaisian pre-zone 7 is very poorly represented by earlandiids, endothyrids, and tournayellids. Septaglomo­ Calcareous secreted foraminifers (endothyrids sensu /ato), spiranella granulosa (Zeller), a diagnostic foraminifer, is girvanellids, and dasycladacean and codiacean algae have present. In contrast, the overlying Tournaisian zone 7 is well been identified in varying amounts in this study. Generally, represented by such characteristic tournayellids as Chernyshi­ foraminifers are scarce to absent in the dolomite and coarse­ nella, Palaeospiroplectammina, and Rectoseptaglomospira­ grained crinoidal packstone. They are most abundant and nella. In the uppermost part of the zone, Tuberendothyra diversified in oolite-peloidal carbonate banks, in algal-lump occurs for the first time, and the genus (T. safonovae Skipp, T. shoals, and in carbonate sand at the edge of the platform or on tuberculata (Chernysheva)) flourishes in zone 8. An interest­ the open platform itself. No foraminifers have been identified ing and characteristic algal micro flora straddles the zone 7-8 in the Las Cruces or Helms Formations. The Hachita Forma­ boundary. Asphaltinella is so abundant in the Escabrosa tion of the Escabrosa Group also is very poor in foraminifers. Limestone that it forms an "Asphaltinella biofacies," locally Although foraminifers and calcareous algae occur sporadi­ associated with Columbiapora and Pekiskopora. A similar cally at all levels within the Mississippian carbonate rocks, distribution is observed in Wyoming and Montana, where the they permit a regional zonation and correlation of the Missis­ "Asphaltinella biofacies" also straddles the boundary between sippian strata. the middle and late Toumaisian (Mamet, 1984). Latest Tournaisian zone 9 is very poor in microfossils be­ cause most of the carbonate rocks at that time were deposited BIOSTRATIGRAPHIC CORRELATIONS in deeper-water environment. Thus, the apparent extinction recorded on figure 10 is quite misleading. In normal-marine, The stratigraphic distribution of 113 microfossil taxa (fo­ shallow-water conditions, toumayellids associated with spino­ raminifers, algae, and incertae sedis) recognized in this study endothyrids would be abundant at this level. The base of the is illustrated in figure 10. Though based on an incomplete rep­ zone is drawn here on the first appearance of the foraminifer resentation of the known ranges elsewhere, this chart permits Priscella. recognition of several assemblages that can be assigned, with The same unfavorable deep-water conditions prevailed varying degree of accuracy, to foraminiferal zones. during early Visean zones 10 and 11. Fauna and flora are quite In the V ekol and Waterman Mountains of Arizona, the very undiversified. The first occurrence of Globoendothyra ap­ thin Escabrosa Limestone was subjected to erosion during proximates the base of the Visean. Stacheeins are present at Late Mississippian and earliest Pennsylvanian time. At these slightly younger levels. No middle Visean fauna has been localities, the Escabrosa Limestone is middle to late Tour­ recorded; this absence is partly due to the widespread paracon­ naisian in age. formity that separates the Keating and Hachita Formations.

18 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico The next identifiable assemblage is basal late Visean zone the data for northwestern New Mexico and the San J nan Basin 14, which is well displayed at the Mule Mountains section. are based on our study of some 100 oil-welllogs. The microfauna contains a rich Eoendothyranopsis assem­ Marine transgressions and regressions during the Late De­ blage, with the characteristic E. macra (Zeller). vonian and earliest Mississippian in southwestern New Mex­ The exact age of the overlying "Brunsia biofacies" is dif­ ico and southern Arizona are believed to be related to Antler ficult to determine. This level is characterized by the prolif­ orogenic events to the northwest in Nevada. These orogenic eration of Brunsia associated with Planoarchaediscus, events are reflected in the regional disconformities within whereas endothyrids, endothyranopsids, and eoendothyranop­ Upper Devonian sedimentary rocks and in the regional hiatus sids are conspicuously scarce or absent. In the Mule Moun­ between Late Devonian and the Early Mississippian (Poole tains, the "Brunsia biofacies" directly overlies zone 14 and is and Sandberg, 1977; Sandberg andPoole,1977; Schumacher, overlain everywhere by zone 16i. We note that the "Brunsia 1978; Cooper and Dutro, 1982; Moore and Barrick, 1988). biofacies" crosses the lithofacies change between the Ran­ The first Mississippian marine transgression, during early cheria Formation in the Florida Mountains and the Hachita Toumaisian (pre-zone 7) time, occurred in the Pedregosa Formation in the Klondike Hills. Basin of southwestern New Mexico, southwestern Arizona, The base of Chesterian zone 16i is generally marked in the and south-central New Mexico. A broad, shallow-water North American Cordillera by the elimination of numerous carbonate shelf developed over the entire region (fig. 11). Meramecian foraminifers, such as Eoforschia and Eoendo­ Carbonate sediment included crinoidal and oolitic sand inter­ thyranopsis. ThisJevel of extinction is not apparent in figure digitated with intertidal to supratidal peloidal micrite, 10 because the widespread "Brunsia biofacies" is itself a level stromatolites, and dolomite. Our interpretation of the lower of major extinction. However, the first occurrence of abun­ part of the Escabrosa carbonates suggests that the environ­ dant Eostaffella and Zellerinella is used to mark the base of ments of deposition were similar to those of the modem Tru­ zone 16i. cial Coast in the Persian Gulf. Escabrosa carbonate rocks have The Chesterian (zones 16i-16s-17-18-19) succession in many sedimentary structures and features in common with the Paradise Formation is quite complete and is similar to that those described by Evans and others (1973), Purser and Evans observed elsewhere in the Cordillera. Zone 16s is marked by (1973), Shinn (1973), and Hardie and Shinn (1986). Concep­ the proliferation of Neoarchaediscus and Planopirodiscus, tual models for the various environments of deposition of the early Namurian zone 17 by abundantAsteroarchaediscus, and Escabrosa Group and the Escabrosa Limestone are shown in zone 18 by numerousBiseriella. Zone 19, recognizable by the figures 12 and 13. The Bugle Member (figs. 15, 16) consists short range of eosigmoilinids, is known only from the Big of a series of incomplete shoaling-upward carbonate cycles Hatchet Mountains succession. Extensive erosion on the Late (Wilson, 1975b; James, 1984; Harris and others, 1985). The Mississippian surface occurred before Pennsylvanian marine intertidal and supratidal facies are best developed in the Ped­ transgression and sedimentation (Armstrong and others, regosa Mountains exposures. The sedimentary structures sug­ 1984 ). The base of Morrowan zone 20 is missing, and the zone gest deposition on a hypersaline tidal flat in an arid climate. is recognized by the first apparent occurrence of Millerella, In contrast, the Witch Memberrepresents sedimentation under associated with primitive Globivalvulina and Glomospiroides deeper water on a subsiding shelf. In fact, the Witch Member spp. A rather important ecologic change is is reflected by ses­ may have been deposited at the edge of the carbonate shelf or sile foraminifers: Quite scarce in the Visean, they became on the upper parts of the carbonate slope. The Escabrosa car­ common in the early Namurian and dominated the earliest bonate slope (fig. 13) is believed to have been gently inclined; Pennsylvanian. A conspicuous change is also observed the slope angle decreased with depth, and the shallow-water among calcareous algae, which are represented in the Pennsyl­ sediment merged imperceptibly into basinal deposits (James, vanian by abundant crustose Archaeolithophyllum, branching 1984; Mcllreath and James, 1984; Mullins, 1986). The end of Donezella,leafy Masloviporidium, and encrusting Osagia. Toumaisian (late Osagean) time was accentuated by a regional marine regression. During late Osagean time, regional uplift, erosion, and removal of most or all of the Lower Mississip­ pian sedimentary rocks took place in south-central New Mex­ MISSISSIPPIAN CARBONATE FACIES AND ico (southern Sacramento Mountains, southern San Andres PALEOTECTONICS Mountains, Franklin Mountains, Florida Mountains, figs. 11, 13, 14). These events, and subsequent deposition of lower The regional isopach map (fig. 1) of the Mississippian strata Meramecian deeper-water carbonates, resulted in a wedge-on­ in southwestern New Mexico and southeastern Arizona is wedge relation, with an angular unconformity between the based on the pre-Pennsylvanian erosional remnants of Missis­ deeply eroded Lake Valley Formation mounds and the deeper­ sippian sedimentary rocks. The isopach contours and subcrop water, starved-basin Rancheria Formation (Laudon and Bow­ map for northeastern New Mexico are from Foster and others sher, 1941, 1949; Lane, 1974; Meyers, 1974; Wilson, 1975a, (1972), and for southeastern New Mexico from Meyer (1966); b; Yurewiez, 1977; Meyers and James, 1978).

Mississippian Carbonate Facies and Paleotectonics 19 ....J ""' Cl) en>­ a: 0...

....IC:::: ca 0~ 20 ~e I II I 19 I I I c:::: I .~-.... t::: I ::::::JECL ca 18 I ca- I 2 I I I I 17 I I I I I I 16s I I I I I I - I I I 16i I I I I i I I I I I I I I I I I I I I I I I I I 1 14-15 I I I I I I I z I I I I I : ~/ I IIJJ Ci5 ~ Hiatus (zones 12-13 missing) ~ ~~,_-,,~------~--·~------,l-r------l----~~-----1--l

I >11 I I I : : : I I : : : I : I 1--- I I : : I I I I I 1 1 I I I - 10 I I I I I I I I I I : : I 1 I I i 11 I I : : I I I I 9 I I I I I I I I 1 I I I I I I I I c:::: ca : I : ·c;; ·n; E - ::::::J 11 0 1- _7_ 7 II ! : i JC::::- I 1I f Cii.~ ~ pre-7 ::;2_g-g

Figure 10. Stratigraphic chart of Mississippian microfossils in 8. Asphaltinel/a sp. southwestern New Mexico and southeastern Arizona, showing 9. Chernyshinella sp. range of foraminifers, calcareous algae, and incertae sedis 1 0. Columbiapora sp. recognized in this study. Microfossils: 11. Columbiapora johnsoni Mamet 1. Calcisphaera /aevis Williamson 12. Earlandia c/avatula (Howchin) 2. Earlandia sp. 13. Earlandia moderata (Malakhova) 3. Earlandia elegans (Rauzer-Chernoussova and Reitlinger) 14. Eotuberitina sp. 4. Earlandia minima (Birina) 15. /ssinella sp. (mainly /.devonica Reitlinger) 5. Kamaena sp. 16. Kamaena itkillikensis Mamet 6. Latiendothyra sp. 17. Latiendothyra /atispiralis (Lipina) 7. Septag/omospiranel/a granulosa (Zeller) 1 8. Mitcheldeania sp.

20 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico I I I I I I I 4 I I I I I I I I I I I I I I • I I I I I I I I I I I I I ! I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I L I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I t I 1 I I I I I I I I I i I

lj

EXPLANATION Last occurrence I Acme Scarce Present Common f First occurrence

19. Palaeoberesella sp. 30. Septaglomospiranella primaeva (Chernysheva) 20. Palaeoberesella lahuseni (von Moller) 31 . Bisphaera sp. 21 . Palaeospiroplectammina sp. 32. Ortonella sp. 22. Palaeospiroplectammina tchernyshinensis (Lipina) 33. Mitcheldeania distans (Coni I and Lys) 23. Parachaetetes sp. and Pseudochaetetes sp. 34. Pekiskopora sp. 24. Parathurammina sp. 35. Spinoendothyra sp. 25. Proninella sp. 36. Tuberendothyra safonovae Skipp 26. Pseudoissinella sp. 37. Tuberendothyra tuberculata (Chernysheva) 27. Radiosphaerina sp. 38. Spinotournayella sp. 28. Rectoseptaglomospiranella sp. 39. Priscella sp. 29. Septabrunsiina sp. 40. Septatournayella pseudocamerata Lip ina in Lebedeva

Mississippian Carbonate Facies and Paleotectonics 21 In New Mexico and Arizona, a regional marine transgres­ bonates lie unconformably on sedimentary rocks of Early Mis­ sion again occurred during middle Visean (Meramecian) time. sissippian and Late Devonian age (fig. 15). A broad carbonate platform developed over the Pedregosa In the Franklin and Florida Mountains of south-central New Basin in much of New Mexico and southeastern Arizona. Car­ Mexico, upper Visean carbonates are represented by deep­ bonate sedimentation in the eastern part of the Pedregosa water sedimentary rocks of the upper part of the Rancheria Basin is represented by the upper part of the Hachita Forma­ Formation and the lower part of the Helms Formation. In the tion, which was deposited as broad areas of bioclastic car­ Pedregosa Basin, the Paradise Formation is a shallow-water, bonate sand and crinoidal packstone. The sand consists of shoaling (zones 15-16 and younger) equivalent of the deeper­ abraded crinoid fragments, smaller amounts of bryozoan frag­ water Rancheria and Helms Formations. ments, and minor amounts of ooids and oolites. To the west The region underwent differential uplift during early Na­ in southeastern Arizona, the carbonate facies in the upper part murian (latest Chesterian) time, and the carbonate terrane was of the Escabrosa Limestone are subtidal, peloidal, micritic exposed to subaerial weathering, vadose solution activity, and packstone and subtidal to intertidal fossiliferous wackestone, dissection. By latest Mississippian and earliest Pennsylvanian lime mudstone, and dolomite (figs. 13, 14). time, well-defined uplifts and basins had developed that were The middle Visean in south-central New Mexico is repre­ to characterize the later Paleozoic deposition. Adjacent to or sented by deeper-water carbonates of the Rancheria Forma­ within this study area are the Zuni-Defiance uplift (McKee, tion in the southern San Andres, Sacramento, and Florida 1951), the Florida uplift, and the Pedregosa and Orogrande Mountains of New Mexico and in the Franklin and Hueco Basins (Kottlowski, 1960, 1963). A regional marine trans­ Mountains of western Texas. These Meramecian cherty car- gression of Bashkirian (early Morrowan) Pennsylvanian age

41. Tournayella discoidea Dain 77. Eostaffella sp. 42. Calcisphaera pachysphaerica (Pronina) 78. Neoarchaediscus sp., primitive 43. Dainella sp. 79. Zellerinella sp. 44. Earlandia vulgaris (Rauzer-Chernoussova and Reitlinger) 80. Cuneiphycus sp. 45. Eblanaia sp. 81 . Koskinotextularia sp. 46. Endothyra sp. 82. Neoarchaediscus sp. 47. Globoendothyra sp. 83. Neoarchaediscus incertus (Grozdilova and Lebedeva) 48. Tetrataxis sp. 84. Neoarchaediscus parvus 49. Eoforschia sp. 85. Nostocites sp. 50. Epistacheoides sp. (mainly E. nephroformis Petryk and 86. Planospirodiscus sp. Mamet) 87. Pseudoendothyra sp. 51. Globoendothyra bridgensis Skipp 88. Zellerinella discoidea (Girty) 52. Stacheoides sp. (mainly 5. meandriformis Mamet and 89. Zellerinel/a designata (Zeller) Rudloff) 90. Asteroarchaediscus sp. 53. Archaediscus sp. 91 . Atractyliopsis sp. 54. Aoujgalia sp. 92. Climacammina sp. 55. Eoendothyranopsiscf. E. ermakiensis (Lebedeva) 93. Planoendothyra sp. 56. Eoendothyranopsis macra (Zeller) 94. Volvotextularia sp. 57. Eoendothyranopsiscf. E. prodigiosa (Armstrong) 95. Apterrinellids 58. Eoendothyranopsis scitula (Toomey) 96. Biseriella sp. (mainly B. parva (Chernysheva)) 59. Globoendothyra cf. G. tomiliensis (Lebedeva) 97. Endothyranopsis sphaerica (Rauzer-Chernoussova and 60. Globoendothyra paula (Vissarionova) Reitlinger) 61. Koninckopora inflata (de Koninck) 98. Koskinobigenerina? sp. 62. Koninckopora tenuiramosa Wood 99. Cribrostomum? sp. 63. Mametella sp. 1 00. Quasiarchaediscus sp. and Eosigmoilina sp. 64. Skippella sp. 1 01. Archaeolithophyllum sp. 65. Stacheoides tenuis Petryk and Mamet 1 02. Calcitornel/a sp. and Calcivertella sp. 66. Asphaltina sp. 1 03. Donezella sp. 67. Asphaltina cordillerensis Mamet 1 04. Fourstonella sp. 68. Brunsia sp. 105. Globivalvulina sp., primitive 69. Nanopora sp. 1 06. Glomospiroides sp. 70. Planoarchaediscus sp. 1 07. Masloviporidium sp. 71. Pseudoammodiscus sp. 1 08. Millerella sp. 72. Pseudoglomospira sp. 1 09. Millerella marblensis Thompson 73. Pseudotaxis sp. 11 0. Millerella pressa Thompson 74. Archaediscus cf. A. chernoussovensis Mamet 111 . Monotaxinoides sp. 75. Archaediscus cf. A. krestovnikovi Rauzer-Chernoussova 112. Osagia sp. 76. Archaediscus koktjubensis Rauzer-Chernoussova 113. Tuberitina sp.

22 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico 112° 1110 11 oo 109° 108° 106°

37"

i ~ ... Pennsylvanian i ...... erosional edge I

r I i r ~~ --~ ------~ ------· - !

0 50 100 150 200 KILOMETERS

EXPlANATION ~ D c~ Precambrian terrane Lower Paleozoic rocks Pre-zone 7 to zone 8 (mostly carbonates) Mississippian carbonates

Figure 11. Western New Mexico and eastern Arizona, showing isopachs (in feet; queried where uncertain) of Lower Mississippian zones pre-7, 7, and 8 and distribution of carbonate rocks in the Pedregosa Basin, northeastern Arizona. Triangles, locations of outcrop sections used in this report.

Mississippian Carbonate Facies and Paleotectonics 23 deposited quartz conglomerate and sand over the eroded Mis­ sia biofacies" is also present at the top of the Hachita Forma-· sissippian surface. These clastic beds are generally succeeded tion and at the base of the Paradise Formation in all outcrop by fossiliferous, fusulinid-bearing limestone. sections in the Pedregosa Basin.

CONCLUSIONS REFERENCES CITED Biostratigraphic correlations among the western, central, Armstrong, A.K., 1962, Stratigraphy and paleontology of the Mis­ and eastern facies are difficult because of numerous paracon­ sissippian System in southwestern New Mexico and adjacent formities, hiatuses, and rapid facies changes from the shelf southeastern Arizona: New Mexico Bureau of Mines and Min­ facies of the Pedregosa Basin to the semi-starved-basin or eral Resources Memoir 8, 95 p. basinal carbonate facies of the Florida and Franklin Moun­ Armstrong, A.K., Kottlowski, F.E., Stewart, W.J., Mamet, B.L., tains. A subsiding, shallow-water to shoaling carbonate shelf Baltz, E.H. Jr., Siemers, W.T., and Thompson, Sam, lll, 1979, developed during Kinderhookian and early Osagean time in The Mississippian and Pennsylvanian (Carboniferous) Systems the central facies, in an area that later became the Pedregosa in the United States-New Mexico: U.S. Geological Survey Basin. Oolitic and bioclastic sand was deposited on this shelf, Professional Paper 1110-W, p. W1-W27. Armstrong, A.K., and Mamet, B.L., 1974, Biostratigraphy of the Ar­ disconformably over Upper Devonian (Famennian) marine royo Penasco Group, Lower Carboniferous (Mississippian), carbonates and shale. The basal Mississippian sedimentary north-central New Mexico, in Siemers, C.T., ed., Central-north­ rocks are separated from the Upper Devonian strata by a major em New Mexico: New Mexico Geological Society Field Con­ hiatus. ference, 25th, Guidebook, p. 145-158. Shallow-water carbonate deposition prevailed nearly con­ -- 1976, Biostratigraphy and regional relations of the Mississip­ tinuously from Osagean through early Meramecian time in the pian Leadville Limestone in the San Juan Mountains, south­ area of the Pedregosa Basin. These carbonates are time western Colorado: U.S. Geological Survey Professional Paper equivalents of the semi-starved-basin deposits of dark-gray, 985,25 p. argillaceous lime mudstone of the Las Cruces Formation in the --1977, Carboniferous microfacies, microfossils, and corals, Lis­ burne Group, Arctic Alaska: U.S. Geological Survey Profes­ Franklin Mountains of Texas. sional Paper 849, 120 p. The only biostratigraphic unit that is recognizable --1978a, The Bugle and Witch Members of the Keating Forma­ throughout the region is the late Visean "Brunsia biofacies," tion, Escabrosa Group, and the Mississippian nomenclature in which occurs at the top of the Escabrosa Limestone in the Ajax the Big Hatchet Mountains, Hidalgo County, New Mexico, in Hills, at Tombstone, and in the Mule Mountains. The "Brun- Sohl, N.E., and Wright, W.B., Changes in stratigraphic

Slope carbonates

Facies Basal carbonates Tidal shelf Crinoid-bioclastic sand Nearshore shelf Crinoid meadows Crinoid-bryozoan meadows

lime mudstone, radiolarian- Encrinite , peloid-crinoid- Encrinite. crinoid- Interbedded th~ to medium- Crinoi~bryozoan-brachiopod Bioclastic wackestone and spiculitic wackestone, brachiopod wackestone, bryozoan packstone . bedded lime mudstone. packstone-wackestone packstone to pelletoidal I lithology silty pelletoidal packstone, and some and arenaceous peloidal dolomite, and chert and lenticular to nodular lime mudstone, with grainstone, and orange arenaceous pelletoidal wackestone chert abundant foraminifers dolomite wackestone I Color Dark brown gray Gray to brown light gray to brown Gray to brown light gray to gray light gray to gray

Intraformational erosional Medium-bedded abundant Crossbedded to massive Thoroughly burrowed, thin Crossbedded to massive Stratified, with abundant surfaces, medium-bedded gray to brown chert beds of nodular gray to medium-bedded, wavy beds of gray nodular ripple marks; bioturbated Bedding and sedimentary angular diastems, and chert to nodular surfaces show- chert gray nodular chert structures abundant clayey shale ing diasterns; dark-gray to black chert

Figure 12. Idealized sequence of standard facies belts for the Escabrosa Group, Escabrosa Limestone, Lake Valley Limestone, Las

24 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico nomenclature by the U.S. Geological Survey, 1977: U.S. Geo­ Dunham, R.J., 1962, Classification of carbonate rocks according to logical Survey Bulletin 1457-A, p. A90-A94. depositional texture, in Ham, W.E., ed., Classification of car­ --1978b, The Mississippian System of southwestern New Mexico bonate rocks: American Association of Petroleum Geologists and southeastern Arizona, in Callender, J.F., Wilt, J.C., and Memoir 1, p. 108-121. Clemons, R.E., ed., Land of Cochise: Southeastern Arizona: Dunn, D.L., 1970, Conodont zonation near the Mississippian-Pen­ New Mexico Geological Society Field Conference, 29th, Guide­ nsylvanian boundary in the western United States: Geological book, p. 183-192. Society of America Bulletin, v. 81, no. 10, p. 2959-2974. Armstrong, A.K., Mamet, B.L., and Burton, R.C., 1984, The Mis­ Evans, Graham, Murray, J.W., Briggs, H.E.J., Bate, R.H., and Bush, sissippian-Pennsylvanian boundary in the Pedregosa Basin in P.R., 1973, The oceanography, ecology, sedimentology and southeastern Arizona and southwestern New Mexico, in Suther­ geomorphology of parts of the Trucial Coast barrier island com­ land, P.K., and Manger, W.L., eds., Biostratigraphy, v. 2 of plex, Persian Gulf, in Purser, B.H., ed., The Persian Gulf: Neuvieme Congres International de Stratigraphie et de Geologie Holocene carbonate sedimentation and diagenesis in a shallow du Carbonifere, Washington, 1979, Compte Rendu: Carbon­ epicontinental sea: New York, Springer-Verlag, p. 233-277. dale, Southern Illinois University Press, p. 399-405. Foster, R.W., Frentress, R.M., Riess, W.C., 1972, Subsurface geolo­ Armstrong, A.K., Mamet, B.L., and Repetski, J.E., 1980, Mississip­ gy of east-central New Mexico: New Mexico Geological pian System of New Mexico and southern Arizona, in Fouch, Society Special Publication 4, 22 p. T.D., and Magathan, E.R., eds., Paleozoic paleogeography of Gilluly, James,Cooper,J.R., andWilliams,J.S.,l954, Late Paleozoic the west-central United States: Rocky Mountain Paleogeog­ stratigraphy of central Cochise County, Arizona: U.S. Geolog­ raphy Symposium 1: Denver, Society of Economic Paleon­ ical Survey Professional Paper 226, 49 p. tologists and Mineralogists, Rocky Mountain Section, p. 82-99. Hardie, L.A., 1977, Sedimentation on the modem carbonate tidal flats Beede, J.W., 1920, Notes on the geology and oil possibilities of the of northwest Andros Island, Bahamas: Baltimore, Johns Hop­ northern Diablo Plateau in Texas: University of Texas Bulletin kins University Press, 202 p. 1852,40 p. Hardie, L.A., and Shinn, E.A., 1986, Tidal flats, carbonate deposi­ Burton, R.C., 1964, A preliminary range chart of Lake Valley For­ tional environments, modem and ancient: Colorado School of mation (Osage) conodonts in the southern Sacremento Moun­ Mines Quarterly, v. 81, no. 1, 874 p. tain, New Mexico, in Ash, S.R., and Davis, L.V., eds., Ruidoso Harris, P.M., Moore, C.H., and Wilson, J.L., 1985, Carbonate plat­ country: New Mexico Geological Society Field Conference, forms, carbonate depositional environments, modem and an­ 15th, Guidebook, p. 73-75. cient: Colorado School of Mines Quarterly, v. 80, no. 4, 60 p. Cooper, G.A., and Dutro, J.T., Jr., 1982, Devonian brachiopods of Hayes, P.T., and Landis, E.R., 1965, Paleozoic stratigraphy of the New Mexico: Bulletins of American Paleontology, v. 82-83, southern part of the Mule Mountains, Arizona: U.S. Geological no. 315, 215 p. Survey Bulletin 1201-F, p. Fl-F43. Cope, E. D., 1882a, Invertebrate fossils from the Lake Valley District, Hernon, R.M., 1935, The Paradise Formation and its fauna: Journal New Mexico: American Naturalist, v. 16, p. 158-159. of Paleontology, v. 9, no. 8, p. 653-696. --1882b, Geologic age of the Lake Valley mines of New Mexico: Herrick, C.L., 1904, Laws of formation of New Mexico mountain Engineering and Mining Journal, v. 34, p. 214. ranges: American Geologist, v. 33, no. 5, p. 301-312. ------,

SALINITY INCREASES

Tidal deltas and tidal Frontal beaches and oolite Restricted platform; subtidal Intertidal zone Supratidal zone Vadose weathering of channels dunes; back beach, algal lagoon and channel zone sabkha surface; carbonate mats, lime mudstone dune sand, calcrete- caliche Bioclastic-oolitic packstone Inclined oolitic packstone, Pelletoidal lime mudstone, Algal mats and stromatolites, Seams and nodules of Coated particles, peloids, and grainstone grainstone, and lime crinoidal wackestone, with skeletal pelletal anhydrite, micrite, and pisolites, alternating mudstone, with algal packstone, and dolomite, carbonate sand and lime dolomite, displaced micro- microlaminae, and limpid mats and tidalite de- with brachiopods and mudstone, dolomite, and fauna, and fine quartz dolomite posits backside ostracodes gypsum sand Gray-yellow-orange light gray to gray light gray light gray to gray light gray to gray Gray-yellow brownish red brownish red yellowish red Stromatolites, with Cross-stratified, with Steeply inclined, cross- Bioturbated, with tidal- pseudomorphs after Anhydrite-gypsum rhombs, large chips and chunks of abundant ripple marks stratified, with scattered channel lag and fill of gypsum; tidal-channel bedded anhydrite, chips, carbonates, with a thick carbonate lithoclasts coarse carbonate material lag and fill of coarse algal mats, and tepee zone of caliche material; bird 's-eye structures structures and chips Cruces Formation, and Rancheria Formation. See figure 4 for explanation of symbols.

Mississippian Carbonate Facies and Paleotectonics 25 t..J a"> s: ~- v;· .:c·Vl "'C ~· ::I -r 0 ::;: ~ ("') ;;.~ 0 ::I

0~

~= o·Cl:l ~ e:. ~ ~1\.0tA~i~RS c:P.i' ~~ ____.z. r;l "'C :r ~e s\OQe ~ "T1 ~ c:ioo'<'a ~ ('\ ((,.O~eo --~· s\oQe ~ '<'a'-e ::Ic.. s: ca~'c,O r:;· ...,.eo9P . 0 ~~/~

./_ - --~.., It) ~ ~ 0 ~ Cl:l ~ __:;· ~ N. 0 ::I ~ ~ ::Ic.. z ~ Figure 13. Block diagram illustrating various facies environments and representative lithostratigraphic units in the Mississippian of southern New Mexico and southeastern s: Arizona. It) )( r:;· 0 112° 111° 110° 107" 106°

• • 0 • • • • • • • • • • • • • • • • • • ~!. . . ~ ......

0 0 ooooooo 0 0 00 0 0 0 0 0 0 0 0 00:, 0 000 0 00 0 0 0 00 00 0 0 0 0 0 0 000 00 0 010 0 0 0 0 0 00 0 0 0 0 0 0'

37' :::·:·:~::-::i;:~~:-:~:••::•:••:A~~r::•-r,::::lt::;~Q;.:.... ':·•:~•••·:-o-:· ~:~/--·-·-- .... ·--0-·-· •.•• :. :. :. :: ••••••.•.•.• :•••••.•. :•. ; •.. :..••.• :•. t:::.:: :::::::: :: ::::: :·:.

3

Precambrian! i (-

34

0 50 100 150 200 KILOMETERS

EXPLANATION Basin carbonates. Rancheria Formation D Shelf carbonates Precambrian Lower Paleozoic Pre-zone 12 Zones 12-15 terrane rocks Mississippian (Meramecian) (mostly carbonates) carbonate rocks carbonate rocks

Figure 14. Western New Mexico and eastern Arizona, showing isopachs (in feet) of Late Mississipian (Meramecian) zones 12 though 15 and facies relation of the basinal Rancheria Formation in the Sacramento, San Andres, Franklin, and Florida Mountains to shallow-water encrinite of the Hachita Formation in the Klondike Hills and Big Hatchet Mountains. Triangles, locations of outcrop sections used in this report. See figure 15 for cross-sectional views along line B-8 '. Mississippian Carbonate Facies and Paleotectonics 27 Huddle, J.W., and Dobrovolny, Ernest, 1952, Devonian and Missis­ New Mexico region: Dallas, Tex., Dallas Geological Society, sippian rocks of central Arizona: U.S. Geological Survey Pro­ p. 119-123. fessional Paper 233-D, p. 67-112. Kurkowski, S.T., 1988, Interim report on the conodont biostratig­ James, N.P., 1984, Shallowing-upward sequences in carbonates, in raphy of the Kelly Limestone (Mississippian), central New Walker, R.G., ed., Facies models (2d ed.): Toronto, Ontario, Mexico [abs.]: New Mexico Geology, v. 10, no. 2, p. 39. Geological Association of Canada (Geoscience Canada Reprint Kues,B.S., 1986, Paleontology of the Caballero and Lake Valley For­ Series, no. 1), p. 213-228. mations (Lower Mississippian) west of the Rio Grande, south­ Kottlowski, F.E., 1960, Summary of Pennsylvanian section in south­ central New Mexico, in Clemons, R.E., King, W.E., and Mack, western New Mexico and southeastern Arizona: New Mexico G.H., eds., Truth or Consequences region: New Mexico Geo­ Bureau of Mines and Mineral Resources Bulletin 66, 187 p. logical Society Field Conference, 37th, Guidebook, p. 203-214. --1963, Paleozoic and Mesozoic strata of southwestern and south­ Lane, H.R., 1974, The Mississippian of southeastern New Mexico central New Mexico: New Mexico Bureau of Mines and Min­ and West Texas-a wedge-on-wedge relation: American As­ eral Resources Bulletin 79, 100 p. sociation of Petroleum Geologists Bulletin, v. 58, no. 2, p. 269- --1970, Paleozoic geologic history of southwestern New Mexico 282. and northwest Chihuahua, in Seewald, Ken, and Sundeen, Dan, --1975, Correlation of the Mississippian rocks of southern New eds., The geologic framework of the Chihuahua tectonic belt: Mexico and west Texas using conodonts, a wedge-on-wedge Midland, West Texas Geological Society, p. 25-38. relation, in Pray, L.C., ed., A guidebook to the Mississippian -- 1975, Mississippian strata of the San Andres Mountains, in shelf edge and basin facies carbonate, Sacramento Mountains Pray, L.C., ed., A guidebook to the Mississippian shelf-edge and and southern New Mexico region: Dallas, Tex., Dallas Geolog­ basin facies carbonates, Sacramento Mountains and southern ical Society, p. 87-98.

WEST BEND IN BEND IN BEND IN BEND IN B SECTION SECTION SECTION SECTION I, I 4 's 17 Is

Pte-Meramecian erosion removed older Mississippian carbonates ------.4

WEST B

BEND IN BEND IN BEND IN BEND IN SECTION SECTION SECTION SECTION 14 •s Is 17 •a /Pre-Pennsylvanian erosional surface Chesterian Paradise Formation I

B

Figure 15. Cross sections along section line 8-B ',illustrating Mississippian carbonate facies, regional relations, and un­ conformities from the Sacramento Mountains of New Mexico, across the Rancheria and Pedregosa Basins, westward to the Escabrosa Limestone of southeastern Arizona. See figure 1 for locations of outcrops (numbered). A, Possible regional extent of Kinderhookian and Osagean carbonates (dashed lines), and area of suggested pre-Meramecian uplift, erosion,

28 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico Laudon, L.R., and Bowsher, A.L., 1941,Mississippianformations of Mcllreath, I.A., and James, N.P., 1984, Carbonate slope, in Walker, Sacramento Mountains, New Mexico: American Association of R.G. ed., Facies models (2d ed.): Toronto, Ontario, Geological Petroleum Geologists Bulletin, v. 25, no. 12, p. 2107-2160. Association of Canada (Geoscience Canada Reprint Series, no. -- 1949, Mississippian formations of southwestern New Mexco: 1), p. 245-257. Geological Society of America Bulletin, v. 60, no. 1, p. 1-87. McKee, E.D., 1951, Sedimentary basins of Arizona and adjoining Mamet, B.L., 1976, An atlas of Carboniferous carbonates in the areas: Geological Society of America Bulletin, v. 62, no. 5, p. Canadian Cordillera: Geological Survey of Canada Bulletin 481-505. 255, 131 p. McKee, E.D., and Gutschick, R.C., 1969, History of the Redwall -- 1984, Carboniferous small foraminifers and stratigraphy, in Limestone of northern Arizona: Geological Society of America Sutherland, P.K., and Manger, W.L., eds., Biostratigraphy, v. 2 Memoir 114, 726 p. of Neuvieme Congres International de Stratigraphie et de Meyer, R.F., 1966, Geology of Pennsylvanian and Wolfcampian Geologie du Carbonif'ere, Washington, 1979, Compte Rendu: rocks in southeast New Mexico: New Mexico Bureau of Mines Carbondale, Southern illinois University Press, p. 3-18. and Mineral Resources, Memoir 17, 123 p. Mamet, B.L., Bamber, E.W., and Macqueen, R.W., 1986, Micro­ Meyers, W.J., 1974, Carbonate cement stratigraphy of the Lake Val­ facies of the Lower Carboniferous Banff Formation and Rundle ley Formation (Mississippian), Sacramento Mountains, New Group, Monkman Pass Map area, Northwest British Columbia: Mexico: Journal of Sedimentary Petrology, v. 44, no. 3, p. 837- Geological Survey of Canada Bulletin 353, 93 p. 861.

BEND IN BEND IN NORTH SECTION SECTION B' BEND IN Hueco Mountatns, Sacramento Mountains, SECTION Texas New Mexico 1 1 1 lg 11 12 13 114

Zone 9 ------1 Zone 8

Zone 7 ------pre:ziinef ------,:-.:_ ::._-..... ~--~~ ~-~~~~~--~-- -- -;::;:;:--- ~- '\" P;;;:·M--;;;i;a-:e~sional surface '\Pte-Merarnectan erosional surface erosional surface

Pte-Meramecian erosion removed all Mtssissippian rocks and extended into ------+oPte-Merameciani Devonian sedimentary rocks erosion of Mississippian carbonates

Sacramento Mountains, New Mexico ---J r-- NORTH BEND IN I SECTION B' Escondtdo, BEND IN sec. 27, T. 18 S, SECTION Nigger Ed R 10 E BEND IN Rancheria Peak. Canyon \ · Dog Canyon, SECTION Hueco Mountains, lsec. 18·, T. 11 S., sec 10, T 18 S., I sec 7, Blk. 9, R 11 E "'i R ~ E. '9 11 El Paso County, Texas 12 13 14 Meramecian erosional surface

FEET 1500 Devonian METERS 300

200 1000

100 500 200 150 100 50 =e~K~IL~O~M~E~TE~R~S~==~O

15~0======1~0=0~~~=5xO======~o o MILES conformity. Datum is top of zone 9. B, Suggested facies and correlation at the end of Meramecian time, showing development of euxinic facies of the Rancheria Formation over Devonian carbonates. Early Meramecian unconformity is projected at base of the Hachita Formation in the Pedregosa Basin.

References Cited 29 -- 1975, Stratigraphy and diagenesis of the Lake Valley Forma­ S toyanow, A.A., 1926, Notes on recent stratigraphic work in Arizona: tion. Sacramento Mountains, in Pray, L.C., ed., A guidebook to American Journal of Science, ser. 5, v. 12, no. 70, p. 311-324. the Mississippian shelf-edge and basin facies carbonates, White, I.C., 1881, Notes on fossils from Lake Valley, New Mexico: Sacramento Mountains and southern New Mexico region: Dal­ American Naturalist, v.15, p. 671. las, Tex., Dallas Geological Society, p. 45-66. Wilson. J .L., 1969, Microfacies and sedimentary structures in"deeper Meyers, W.J., and James, A.T., 1978, Stable isotopes of cherts and water" lime mudstones, in Friedman, G.M., ed., Depositional carbonate cements in the Lake Valley Formation (Mississip­ environments in carbonate rocks: A symposium: Society of pian), Sacramento Mts, New Mexico: Sedimentology, v. 25, no. Economic Paleontologists and Mineralogists Special Publica­ 1, p. 105-124. tion 14, p. 4-19. Moore, Darrell, and Barrick, I.E., 1988, Upper Devonian-Lower Mis­ --1971, Upper Paleozoic history of the western Diablo Platform, sissippian conodont biostratigraphy and depositional patterns, west Texas and south-central New Mexico, in Seewald, Ken, southwestern New Mexico and southeastern Arizona: New and Sundeen, Dan, eds., The geologic framework of the Chi­ Mexico Geology, v. 10, no. 2, p. 25-32. huahua tectonic belt: Midland, West Texas Geological Society, Mullins, H.T., 1986, Periplatform carbonates, carbonate deposition­ p. 57-64. al environments, modem and ancient: Colorado School of -- 1975a, Carbonate facies in geologic history: New York, Mines Quarterly, v. 81, no. 2, 63 p. Springer-Verlag, 471 p. Poole, F.G., and Sandberg, C.A., 1977, Mississippian paleogeog­ --1975b, Regional Mississippian facies and thickness in southern raphy and tectonic of the western United States, in Stewart, J.H., New Mexico and Chihuahua, in Pray, L.C., ed., A guidebook to Stevens, C.H., and Fritsche, A.E., eds., Paleozoic paleogeog­ the Mississippian shelf-edge and basin facies carbonates, Sacra­ raphy of the western United States: Pacific Coast Paleogeo­ mento Mountains and southern New Mexico region: Dallas, graphic Symposium 1: Los Angeles, Society of Economic Tex., Dallas Geological Society, p. 124-128. Paleontologists and Mineralogists, Pacific Section, p. 39-65. Yurewicz, D.A., 1973, Genesis of the Rancheria and Las Cruces(?) Pray, L.C., 1958, Fenestrate bryozoan core facies, Mississippian Formations (Mississippian) of south-central New Mexico and bioherms, southwestern United States: Journal of Sedimentary west Texas: Madison, University ofWisconsin. M.S. thesis, 249 Petrology, v. 28, no. 3, p. 261-273. p. Purser, B.H., and Evans, Graham, 1973, Regional sedimentation --1977, Sedimentology of Mississippian basin-facies carbonates, along the Trucial Coast, southeast Persian Gulf, in Purser, B .H., New Mexico and west Texas--the Rancheria Formation, in ed., The Persian Gulf: Holocene carbonate sedimentation and Cook, H.E., and Enos, Paul, eds., Deep-water carbonate environ­ diagenesis in a shallow epicontinental sea: New York, Springer­ ments: Society of Economic Paleontologists and Mineralogists Verlag, p. 211-231. Special Publication 25, p. 203-219. Ransome, F.L., 1904, The geology and ore deposits of the Bisbee Zeller, R.A., Jr., 1965, Stratigraphy of the Big Hatchet Mountains quadrangle, Arizona: U.S. Geological Survey Professional Pa­ area, New Mexico: New Mexico Bureau of Mines and Mineral per 21, 168 p. Resources Memoir 16, 128 p. Sabins, F.F., Jr., 1957, Stratigraphic relations in Chiricahua and Dos Cabezas Mountains, Arizona: American Association of Petro­ leum Geologists Bulletin, v. 41, no. 3 p. 466-510. SUPPLEMENTARY DATA: DETAILED Sandberg, C.A., and Poole, F.G., 1977, Conodont biostratigraphy and BIOSTRATIGRAPHY depositional complexes of Upper Devonian cratonic-platform and continental-shelf rocks in the western United States, in M ur­ Numbers refer to the locations of sections shown in figure phy, M.A., Berry, W.B.N., and Sandberg, C.A., eds., Western 4. North America: Devonian: Riverside, University of California, Campus Museum Contribution 4, p. 144-182. 1. Vekol Mountains Sando, W .J., and Bamber, E. W., 1985, Coral zonation of the Missis­ sippian System in the Western Interior Province of North Amer­ 55-67m ica: U.S. Geological Survey Professional Paper 1334, 61 p. Sando, W.J., Mamet, B.L., and Dutro, J.T., Jr., 1969, Carboniferous Asphaltinella sp., abundant megafossil and microfossil zonation in the northern Cordillera Calcisphaera sp. of the United States: U.S. Geological Survey Professional Paper Columbiapora sp. 613-E, p E1-E29. Earlandia sp. Schumacher, Dietmar, 1978, Devonian stratigraphy and correlations Eotuberitina sp. in southeastern Arizona, in Callender, J.P., Wilt, J.C., and Clem­ lssinella sp. Kamaena sp. ons, R.E., ed., Land of Cochise: Southeastern Arizona: New Latiendothyra latispiralis (Lipina) Mexico Geological Society Field Conference, 29th, Guidebook, Palaeoberesella sp. p. 175- 181. Palaeospiroplectammina sp. Shinn, E.A., 1973, Carbonate coastal accretion in an areaoflongshore Parathurammina sp. transport, northeast Qatar, Persian Gulf, in Purser, B .H., ed., The Proninella sp. Persian Gulf: Holocene carbonate sedimentation and diagenesis Pseudoissinella sp. in a shallow epicontinental sea: New York, Springer-Verlag, p. Septabrunsiina sp. 180-191. Septaglomospiranella prima eva (Chemysheva)

30 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico Age: zone 7, middle Toumaisian; "Asphaltinella biofacies" Ear/andia sp. G/obiva/vu/ina? sp. 99-104m cf. Pseudostaffella sp. Zellerinella sp. Asphaltinella sp., abundant Kamaena sp. Age: at least zone 20, Morrowan or Atokan age equivalent, Bashkirian M itchelckania sp. Palaeospiroplectammina chernyshinensis (Lip ina) 3. Whetstone Mountains Proninella sp. Septabrunsiina sp. 62.5m Septaglomospiranella sp. Aspha/tinella sp. Calcisphaera laevis Williamson Age: at least zone 7 (or slightly younger, zone 8), middle to late Tour­ Ear/andia sp. naisian; "Asphaltinella biofacies" Kamaena sp. Latiendothyra sp. 155-163 m M itchelckania sp. Palaeoberesella lahuseni (von Moller) Apterrinellids Palaeospiroplectammina tchernyshinensis (Lipina) Archaeolithophyllum sp. Parathurammina sp. Asteroarchaediscus sp. Septabrunsiina sp. Biseriella sp. Septag lomospiranella primaeva (Chemysheva) Calcitornella sp. Calcivertella sp. Age: zone 7, middle Toumaisian; "Aspha/tinella biofacies" Eostaffella sp. cf. Globivalvu/ina sp. 71-87m Neoarchaediscus sp. Osagia sp. Asphaltinella sp. Planospirodiscus sp. Calcisphaera laevis Williamson Pseudoendothyra sp. Columbiapora sp. Pseudoglomospira sp. Earlandia clavatu/a (Howchin) Zellerinella sp. lssinella sp. Latiendothyra sp. Age: zone 20, Morrowan age equivalent, Bashkirian M itchelckania dis tans (Conil and Lys) Ortonella sp. 2. Waterman Mountains Palaeoberesella sp. Parathurammina sp. I 2-20m Pekiskopora sp. Proninella sp. Asphaltinella sp. Pseudoissinella sp. Calcisphaera laevis Williamson Radiosphaerina sp. Earlandia sp. Septabrunsiina sp. Chernyshinella sp. Septaglomospiranella sp. Septaglomospiranella primaeva (Chemysheva) Septatournayella sp. Spinoendothyra sp., primitive Age: zone 7, middle Toumaisian T uberendothyra safonovae Skipp tubercula/a (Chemysheva) 45-65m Age: zone 8,late Toumaisian; "Asphaltinella-Columbiapora biofacies" Asphaltinella sp. Calcisphaera sp. 172m Earlandia sp. Kamaena sp. Calcisphaera laevis Williamson Latiendothyra sp. Earlandia clavatu/a (Howchin) Ortonella sp. Kamaena sp. Parathurammina sp. Priscella sp. Proninella sp. Septatournayella pseudocamerata Lipina in Lebedeva Septag/omospiranella sp. Septatournayella sp. Age: zone 9,latest Toumaisian Spinotournayella sp. Tuberendothyra tubercu/ata (Chemysheva) 209m

Age: zone 8, late Toumaisian; "Asphaltine//a biofacies" Earlandia vulgaris (Rauzer-Chemoussova and Reitlinger) Globoendothyra sp. 78m Priscella sp. T etrataxis sp. Biseriella sp. Ca/cisphaera sp. Age: zone 10, early Visean

Supplementary Data: Detailed Biostratigraphy 31 229m Palaeospiroplectammina sp. Proninella sp. Asteroarchaediscus sp. Pseudoissinella sp. Biseriella sp. Septabrunsiina sp. Cuneiphycus sp. Septaglomospiranella sp. cf. Donezella sp. primaeva (Chemysheva) Globivalvulina sp., primitive Toumayellids Monotaxinoides sp. Neoarchaediscus sp. Age: high zone 7, middle Toumaisian; "Asphaltinella-Columbiapora Planospirodiscus sp. biofacies" Stacheoides sp. 18m Tuberitina sp. Asphaltinella sp., abundant Age: zone 20, Morrowan age equivalent, Bashkirian Bisphaera sp. Calcisphaera sp. 4. Ajax Hills Columbiapora sp. Earlandia sp. 83-114m lssinella sp. l.Atiendothyra sp. Asphaltinella sp. Palaeospiroplectammina sp. Columbiapora sp. Proninella sp. Earlandia moderate (Malakhova) Pseudoissinella sp. l.Atiendothyra sp. Septabrunsiina sp. Palaeospiroplectammina tchernyshinensis (Lipina) Septaglomospiranella sp. Parachaetetes? sp. cf. Tuberendothyra? sp. Parathurammina sp. Rectoseptaglomospiranella sp. Age: high zone 7, middle Toumaisian (or slightly younger?); "Asphal­ Septabrunsiina sp. tinella-Columbiapora biofacies" Septaglomospiranella primaeva (Chemysheva) 30-41 m Age: zone 7, middle Toumaisian; "Asphaltinella-Columbiapora biofacies" Asphaltinella, abundant Bisphaera sp. 274-283 m Calcisphaera sp. Archaediscus sp. Columbiapora sp. Asphaltina cordillerensis Mamet Earlandia sp. Brunsia sp., abundant l.Atiendothyra sp. Earlandia sp. Ortonella sp. Pseudoglomospira sp. Palaeospiroplectammina sp. Parathurammina sp. Age: zone 14-15, late Visean; "Brunsia biofacies" Pseudoissinella sp. Radiosphaerina sp. 303m Septabrunsiina sp. Septaglomospiranella sp. Archaeolithophyllum sp. primaeva (Chemysheva) Asteroarchaediscus sp. Solenoporid algae Biseriella sp. Tuberendothyra sp. Climacammina sp. Endot hyra sp. Age: zone 8, early late Toumaisian; "Asphaltinella-Columbiapora Eostaffella sp. biofacies" Millerella sp. Neoarchaediscus sp. 123-131 m Pseudoendothyra sp. Pseudoglomospira sp. Calcisphaera sp. Zellerinella sp. Earlandia sp. lssinella sp. Age: zone 20, Morrowan age equivalent, Bashkirian Kamaena sp. Septabrunsiina sp. 5. Mule Mountains Septatournayella pseudocamerata Lipina in Lebedeva Spinoendothyrids 7-15m T ournayella sp.

Asphaltinella sp., abundant Age: zone 9, latest Toumaisian Calcisphaera sp. Columbiapora johnsoni Mamet 134-140m Earlandia sp. lssinella sp. First occurrence of Visean foraminifers (post-zone 10) l.Atiendothyra sp. Calcisphaera pachysphaerica (Pronina)

32 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico Dainella sp. P/anoarchaediscus sp. Earlandia sp. Eblanaia sp. Age: zone 14-15, late Visean; "Brunsia biofacies" Globoendothyra sp. 220-233m 143-152m Apterrinellids Calcisphaera laevis Williamson Archaediscus sp. pachysphaerica (Pronina) Archaeolithophyllum sp. Earlandia vulgaris (Rauzer-Chemoussova and Reitlinger) Asteroarchaediscus sp. Endothyra sp. Biseriella sp. Eoforschia sp. Climacammina sp. Epistacheoides nephroformis Petryk and Mamet Cuneiphycus sp. Globoendothyra bridgensis Skipp Donezella sp. lssinella sp. Earlandia sp. Palaeoberesella lahuseni (von Moller) Endothyra sp. Stacheoides sp. Eostaffella sp. M illerella marblensis Thompson Age: undetermined lower to middle Visean (at least zone 11) Neoarchaediscus sp. Planospirodiscus sp. 184-200m Pseudoendothyra sp. Tetrataxis sp. Asphaltina cordillerensis Mamet Zellerinella sp. Brunsia sp. Calcisphaera laevis Williamson Age: zone 20, Morrowan age equivalent, Bashkirian pachysphaerica (Pronina) Earlandia vulgaris (Rauzer-Chemoussova and Reitlinger), abundant 6. Pedregosa Mountains Endothyra simi/is Rauzer-Chemoussova and Reitlinger Globoendothyra tomiliensis (Lebedeva) 49-52m Mametella skimoensis (Mamet and Rudloff) Palaeoberesella sp. Earlandia minima (Birina) Priscella sp. Latiendothyra sp. Tetrataxis angusta Vissarionova Septaglomospiranella granulosa (Zeller)

Age: zone 13-14, early late Visean Age: pre-zone 7, middle Toumaisian 104-122m 2~206m Earlandia elegans (Rauzer-Chemoussova and Reitlinger) Aoujgalia sp. minima (Birina) Archaediscus sp. Kamaena itkillikensis Mamet Calcisphaera pachysphaerica (Pronina) Latiendothyra sp. Earlandia clavatula (Howchin) Palaeoberesella sp. elegans (Rauzer-Chemoussova and Reitlinger) Palaeospiroplectammina tchernyshinensis (Lipina) vulgaris (Rauzer-Chemoussova and Reitlinger) Radiosphaerina sp. Endothyra sp. Rectoseptaglomospiranella sp. simi/is Rauzer-Chemoussova and Reitlinger Septaglomospiranella sp. Eoendothyranopsis of the group E. ermakiensis (Lebedeva) primaeva (Chemysheva) macra (Zeller) cf. E. prodigiosa (Armstrong) scitula (foomey) Age: zone 7, middle Toumaisian Epistacheoides nephroformis Mamet and Petryk Globoendothyra cf. G. tomiliensis (Lebedeva) 242-260m paula (Vissarionova) Koninckopora inflata (de Koninck) Asphaltina sp. tenuiramosa Wood Brunsia sp., very abundant Mametella sp. Calcisphaera sp. Skippella sp. Earlandia sp. Priscella sp. Epistacheoides sp. Stacheoides meandriformis Mamet and Rudloff Planoarchaediscus sp. tenuis Petryk and Mamet Pseudoammodiscus sp. Tetrataxis sp. Pseudoglomospira sp. Pseudotaxis sp. Age: zone 14, early late Visean Age: zone 14-15, late Visean; "Brunsia biofacies" 206-209m No diagnostic foraminifers at the base of the Paradise Formation; some Brunsia sp. (abundant) calcispheres, endothyrids (Priscella), and stacheeins. Calcisphaera sp. Earlandia sp. 422-425m

Supplementary Data: Detailed Biostratigraphy 33 Archaediscus sp. Asteroarchaediscus sp. Calcisphaera sp. Biseriella sp. Earlandia sp. Climacammina sp. Endothyra sp. Endothyra sp. Eostaffella sp. Eostaffella sp. Globoendothyra sp. cf. Globivalvulina sp. Koskinotextularia sp. Glomospiroides sp. Neoarchaediscus sp. Millerella sp. Planospirodiscus sp. Neoarchaediscus sp. Priscella sp. Planoendothyra sp. Pseudoendothyra sp. Planospirodiscus sp. Stacheoides sp. Priscella sp. Zellerinella sp. Pseudoammodiscus sp. Pseudoendothyra sp. Age: zone 16sup, latest Visean (or slightly younger) Pseudoglomospira sp. Zellerinella sp. 433-450m Age: zone 20, Morrowan age equivalent, Bashkirian Archaediscus sp. Asteroarchaediscus sp. 7. Big Hatchet Mountains Calcisphaera sp. Climacammina sp. 40-55m Earlandia sp. Endothyra sp. Calcisphaera laevis Williamson Eostaffella sp. Earlandia elegans (Rauzer-Chemoussova and Reitlinger) Eotuberitina sp. Kamaena sp. Koskinobigenerina? sp. Latiendothyra sp. Neoarchaediscus sp. Septaglomospiranella granulosa (Zeller) Planoendothyra? sp. Planospirodiscus sp. Age: pre-zone 7, middle Toumaisian Priscella sp. Pseudoammodiscus sp. 137-170m Pseudoendothyra sp. Pseudoglomospira sp. Calcisphaera laevis Williamson Stacheoides sp. Earlandia clavatula (How chin) Zellerinella sp. Latiendothyra sp. Palaeospiroplectammina sp. Age: zone 17, earliest Namurian Septaglomospiranella primaeva (Chemysheva)

465-473m Age: zone 7, middle Toumaisian

Apterrinellids 265-269m Archaediscus sp. Asteroarchaediscus sp. Archaediscus sp. Biseriella sp. Asphaltina sp. Calcisphaera sp. Brunsia sp., abundant Climacammina sp. Calcisphaera sp. Consobrinella sp. Endothyra sp. Cuneiphycus sp. Planoarchaediscus sp. Endothyra sp. Pseudoammodiscus sp. Endothyranopsis sphaerica (Rauzer-Chemoussova and Reitlinger) Eostaffella sp. Age: zone 14-15, late Visean; "Brunsia biofacies" Epistacheoides nephroformis Petryk and Mamet Neoarchaediscus sp. 28Cr291 m Planoendothyra sp. Planospirodiscus sp. Archaediscus sp. Priscella sp. Asphaltina sp. Pseudoendothyra sp. Brunsia sp. Stacheoides sp. Calcisphaera sp. Zellerinella sp. Endothyra sp. Eostaffella sp. Age: zone 18, early Namurian Eotuberitina sp. Neoarchaediscus sp., primitive 483-512m Priscella sp. Pseudoammodiscus sp. Aoujgalia sp. Pseudoglomospira sp. Apterrinellids Stacheoides sp. Archaediscus sp. T etrataxis sp.

34 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico Zellerinella sp. Asteroarchaediscus sp. Biseriella sp. Age: zone 16inf, late Visean Calcisphaera sp. Climacammina sp. 309-312m Eostaffella sp. Neoarchaediscus sp. Archaediscus sp. Planospirodiscus sp. Brunsia sp. taimyricus Sossipatrova Calcisphaera sp. Priscella sp. Endothyra sp. Pseudoammodiscus sp. Eostaffella sp. Pseudoen.dothyra sp. Eotuberitina sp. Pseudoglomospira sp. Neoarchaediscus sp., primitive Pseudotaxis sp. Priscella sp. Quasiarchaediscus sp. Pseudoammodiscus sp. Stacheoides sp. Pseudoglomospira sp. Zellerinella sp. Stacheoides sp. T etrataxis sp. Age: zone 19, early Namurian Zellerinella sp. 402-411 m Age: zone 16inf, late Visean Apterrinellids 319-363 m Asteroarchaediscus sp. Biseriella sp. Aoujgalia sp. Endothyra sp. Archaediscus sp. Eostaffella sp. Asphaltina sp. Fourstofll!lla sp. Asteroarchaediscus sp. Glomospiroides sp. Atractyliopsis sp. Millerella marblensis Thompson Calcisphaera sp. pressa Thompson Climacammina sp. Planoendothyra sp. Endot hyra sp. Pseudoen.dothyra sp. Epistacheoides sp. Pseudoglomospira sp. Neoarchaediscus sp. Stacheoides sp. Priscella sp. Volvotextularia sp. Pseudoen.dothyra sp. Zellerinella sp. Pseudoglomospira sp. Pseudotaxis sp. Age: zone 20, Morrowan age equivalent, Bashkirian Stacheoides sp. Zellerinella sp. 8. Klondike Hills Age: zone 17, earliest Namurian 24-30m 365-387m Calcisphaera laevis Williamson Aoujgalia sp. Earlandia minima (Birina) Apterrinellids sp. Archaediscus sp. Latiendothyra sp. Asphaltina sp. Septaglomospiranella granulosa (Zeller) Asteroarchaediscus sp. Biseriella sp. Age: pre-zone 7, middle Toumaisian Calcisphaera sp. Climacammina sp. 79-82m Endothyra sp. Eostaffella sp. Asphaltina sp. Neoarchaediscus sp. Brunsia sp., abundant Planospirodiscus sp. Nanopora sp. Priscella sp. Planoarchaediscus sp. Pseudoammodiscus sp. Pseudoen.dothyra sp. Age: zone 14-15, late Visean; "Brunsia biofacies," similarto the base Pseudoglomospira sp. of the Paradise Formation in the Big Hatchet section Stacheoides sp. Zellerinella sp. 88-91 m

Age: zone 18, early Namurian Archaediscus koktjubensis Rauzer-Chemoussova krestovnikovi Rauzer-Chemoussova 389-397m Asphalt ina cordillerensis Mamet Apterrinellids Brunsia sp. Archaediscus sp. Calcisphaera sp.

Supplementary Data: Detailed Biostratigraphy 35 Earlandia sp. Asphaltina sp. Endothyra sp. Asteroarchaediscus sp. Eostaffella sp. Biseriella sp. Stacheoides sp. Climacammina sp. Zellerinella sp. Cuneiphycus sp. Endothyra sp. Age: zone 16inf,late Visean Eostaffella sp. Koskinobigenerina sp. 102-105m Koskinotextularia sp. Neoarchaediscus sp. Archaediscus cf. A. chernoussovensis Mamet Planospirodiscus sp. Archaediscus cf. A. krestovnikovi Rauzer-Chemoussova Priscella sp. Calcisphaera sp. Stacheoides sp. Earlandia sp. Zellerinella sp. Endothyra sp. Eostaffella sp. Age: zone 18, early Namurian Neoarchaediscus sp. Priscella sp. 150-155 m Stacheoides sp. Zellerinella sp. Archaediscus sp. Asteroarchaediscus sp. Age: zone 16in(,late Visean Earlandia sp. M illerella sp. 112-118 m Neoarchaediscus sp. Priscella sp. Archaediscus cf. A. krestovnikovi Rauzer-Chemoussova Pseudoendothyra sp. Asphaltina sp. Stacheoides sp. Calcisphaera sp. T etrataxis sp. Cuneiphycus sp. Zellerinella sp. Earlandia sp. Endothyra sp. Age: zone 20, Morrowan age equivalent, Bashkirian Eostaffella sp. Neoarchaediscus sp. 9. Florida Mountains Nostocites sp. Planospirodiscus sp. 20-36m Stacheoides sp. Zellerinella sp. Brunsia sp., abundant Calcisphaera sp. Age: zone 16sup,latest Visean Earlandia sp. Eotuberitina sp. 123-135 m Palaeoberesella sp.

Archaediscus sp. Age: zone 14-15,late Visean; "Brunsia biofacies" Asphaltina sp. Asteroarchaediscus sp. 52-58m Calcisphaera sp. Cuneiphycus sp. Apterrinellids Earlandia sp. Epimastopora sp. Endothyra sp. Eugonophylum sp. Eostaffella sp. Globivalvulina sp. Girvanella sp. Protonodosaria sp. Globoendothyra sp. T etrataxis sp. Mitcheldeania sp. Tubiphytes sp. Neoarchaediscus incertus (Grozdilova and Lebedeva) Planospirodiscus sp. Age: Early Permian Priscella sp. Sphinctoporella sp. Stacheoides meandriformis Petryk and Mamet 10. Vinton Canyon T etrataxis sp. Volvotextularia sp. 23-29m Zellerinella discoidea (Girty) Archaediscus sp. Brunsia sp. (abundant). Age: zone 17, earliest Namurian Calcisphaera laevis Williamson Pseudoammodiscus sp. 137-142m

Archaediscus sp. Age: zone 14-15,late Visean; "Brunsia biofacies"

36 Mississippian (lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico 61~m Age: zone 17, earliest Namurian

Archaediscus sp. 167-176m Calcisphaera sp. Neoarchaedidcus sp., primitive cf. Aoujgalia sp. Priscella sp. Apterrinellids Pseudoammodiscus sp. Asphaltina cordillerensis Mamet Zellerinella sp. Biseriella sp. Age: zone 16i, late Visean Calcisphaera sp. Cuneiphycus sp. Earlandia sp. 91-93m Endothyra sp. Eostaffella sp. Calcisphaera sp. Eotuberitina sp. Neoarchaediscus sp. Epistacheoides sp. Planospirodiscus sp. Fasciella sp. Priscella sp. Globivalvulina sp., primitive Masloviporidium sp. Age: zone 16s, latest Visean M illerella sp. Palaeoberesella sp. 103-114m Priscella sp. Pseudoglomospira sp. Stacheoi.des sp. Archaediscus sp. T etrataxis sp. Asteroarchaediscus sp. Volvotextularia sp. Calcisphaera sp. Zellerinella sp. Neoarchaediscus sp. Priscella sp. Zellerinella sp. Age: zone 20, Morrowan age equivalent, Bashkirian

Supplementary Data: Detailed Biostratigraphy 37

INDEX

[Italic page IlUIIlben indicate principal references]

A c Echinoderms--Continued Witch Member, Keating Formation, 10 Acrocyathus? shimeri, 8 Caballero Formation, 2, 8, 10, 16 El Paso, Tex., 5 Adetognathus, 15 Calcite, 11, 16, 17 Encrinite, 8, 13, 17 gigantus, 14 Carbonates, 1, 8, 10, 13, 16, 19, 22, 24 Endothyranopsids, 19 lautus, 14 Cathodoluminescence, 16 Endothyrids, 18, 19 Ajax Hills, Ariz., 8, 16, 17, 18,24 Cavities, see Erosion Eoendothyranopsids, 19 Alaska, 13 Cavusgnathus, 14 Eoen.dothyranopsis, 19 Algae, 1, 18 un.icornis, 14 macra, 19 Bugle Member, Keating Formation, 9, 17 spp., 17 Eoforschia, 19 Escabrosa Group, 17 Cephalopods, Paradise Formation, 13 Eosigmoilinids, 19 Escabrosa Limestone, 8, 16, 18 Chernysheva, 18 Eostaffella, 19 Hachita Formation, 11, 18 Chernyshinella, 18 Erosion, 2, 8, 16, 17, 18, 19 Helms Formation, 18 Chert, 8, 9, 10, 11, 16, 17, 18 Escabrosa Cliffs, Ariz., 2 Las Cruces Formation, 18 Chihuahua, Mexico, 13 Escabrosa Group, 9, 16 Paradise Formation, 14 Chiricahua Mountains, Ariz.-N.Mex., 2, 3, 8, 9, 11, Boss Ranch section, 17 americanus, Gon.iatites, 13 13, 15 Hachita Formation, 11 Amplexizaphrentis spp., 13 Clastic rocks, 13, 16, 24 Keating Formation, 9 Analyses, 1, 5, 16 Clay, 8, 15 Esca brosa Limestone, 2, 9 Andrecito Member, Lake Valley Formation, 10 Climate, 19 Central facies, 17 Anhydrite, 17 Cochise County, Ariz., 2 Eastern facies, 18 Antler orogen, 19 Columbiapora, 8, 17, 18 Western facies, 8, 13, 15 Archaeolithophyllum, 19 communis, Polygnathus, 13, 17 Eumorphoceras, 14, 15 Archimedes, 14 Polygnathus communis, 13 Evaporites, 9 Asphaltinella, 8, 17, 18 communis communis, Polygnathus, 13 "Asphaltinella biofacies," Escabrosa Limestone, 18 commutatus, Gnathodus, 15 F Asteroarchaediscus, 19 Confusion Range, Utah, 13 Conglomerate, 8, 14, 24 Florida Mountains, N.Mex., 5, 8, 16, 17, 19, 22,24 B Conodont-alteration index (CAl), 13 Florida uplift, 8, 22 Conodonts, 8 Foraminifers, 1, 18 bassleri, Gnathodus bassleri, 14 Hachita Formation, 13 Bugle Member, Keating Formation, 18 bassleri bassleri, Gnathodus, 17 Helms Formation, 16 Hachita Formation, 11, 17 symmetricus, Gnathodus, 14 Horquilla Limestone, 14 Horquilla Limestone, 14 Big Hatchet Mountains, N.Mex., 3, 5, 8, 9, 11, 13, Lake Valley Limestone, 16 Martin Formation, 18 14, 18, 19 Paradise Formation, 15 Paradise Formation, 13, 15 bilineatus, Gnathodus, 14, 17 Rancheria Formation, 16 Rancheria Formation, 16 Bioherms, Lake Valley Formation, 16 Corals, 1 Witch Member, Keating Formation, 17 Biostratigraphic correlations, 18, 24 Bugle Member, Keating Formation, 9, 17, 18 forbesi, 1mbrexia, 10 Bird's-eyes, 9, 10 Escabrosa Limestone, 8 Franklin Mountains, Tex., 1, 2, 5, 8, 16, 19, 22, 24 Bisbee, Ariz., 2, 16 Hachita Formation, 13 Fusulinids, 8, 24 Biseriella, 19 Horquilla Limestone, 14 Bispathodus stabilis, 13 Paradise Formation, 17 Bispathodus? spp., 13 Cordillera, 13, 18 G Blue Mountain, N.Mex., 3, 8, 11, 13, 14 Crinoids, 1, 18, 22 Boss Ranch, see Escabrosa Group Bugle Member, Keating Formation, 17 Gastrioceras, 14 Box Member, Percha Shale, 8, 18 Escabrosa Limestone, 16 gigantus, Adetognathus, 14 Brachiopods, 1 Hachita Formation, 11, 13, 17 girtyi simplex, Gnathodus, 14 Escabrosa Limestone, 16 Paradise Formation, 14 Girtyoceras spp., 13 Hachita Formation, 11, 13, 17 cristulus, Spathognathodus, 17 Girvanellids, 18 Paradise Formation, 13, 17 Globivalvulina, 19 Witch Member, Keating Formation, 10 D Globoen.dothyra, 18 Brachycycloceras spp., 13 Glomospiroides spp., 19 Brachythyris subcardiiformis, 13 Declinognathodus noduliferus, 14 Gnathodus bassleri bassleri, 14 BrUliSia, 19 Diagenesis, 1, 16 bassleri symmetricus, 14 "B run.sia biofacies," 19, 24 Disconformities, 8, 9, 18, 19, 24 bilineatus, 14, 17 Escabrosa Limestone, 18 Dolomite, 9,10,16,17,18,19, 22 commutatus, 15 Hachita Formation, 13 Donezella, 19 girtyi simplex, 14 Paradise Formation, 14 Dos Cabezas, Ariz., 13 texanus, 15, 17 Rancheria Formation, 16 spp., 17 Bryozoans, 1 E Goniatites, 14, 15 Escabrosa Limestone, 16 Gon.iatites americanus, 13 Hachita Formation, 11, 13, 17 Earlandiids, 18 spp., 13 Paradise Formation, 13, 17 Echinoderms, Bugle Member, Keating Formation, 9 Gordon, MacKenzie, Jr., quoted, 13 Witch Member, Keating Formation, 10 Escabrosa Limestone, 16 Grainstone, 9, 11, 13, 14, 17, 18 Bugle Member, Keating Formation, 3, 8, 9, 17, 18, Hachita Formation, 11 granulosa, Septaglomospiranella, 18 19 Tierra Blanca Member, Lake Valley Formation, 13 Gunnison Hills, N.Mex., 8, 16

Index 39 H Neoprioniodiform, 17 St. Louis Limestone, 14 Neoprioniodus, 14 Ste. Genevieve Limestone, 14 Hachita Formation, 3, 8,11, 14, 17, 18, 19, 22,24 loxus, 15 San Andres Mountains, N.Mex., 2, 16, 17, 19, 22 Hehns Formation, 2, 8, 16, 17, 18, 22 Nodular chert, 10, 14 San Juan Basin, 19 Hematite, 14 noduliferus, Declinognathodus, 14 Sandstone, 8, 13, 18 Hibbardella milleri, 15 Sedimentary structures, 8 Hibbardelliform, 17 0 Escabrosa Limestone, 16, 17 Hindeodelliform, 17 Keating Formation, Bugle Member, 9 Horquilla Limestone, 14 obovatum, Lepidodendron, 14 Witch Member, 10 Hueco Formation, 8 Onchodiniform, 13 Septaglomospiranella granulosa, 18 Hueco Mountains, Tex., 2, 22 Ooids, 22 Shale, 8, 9, 13, 14, 16, 17, 18,24 Escabrosa Limestone, 16 shimeri, Acrocyathus?, 8 I,K 1-Iorquilla Limestone, 14 Silica, 10 Paradise Formation, 13 Siltstone, 13, 17 Igonodiniform, 13 Oolites,&, 18,22,24 simplex, Gnathodus girtyi, 14 Imbrexi.aforbesi, 10 Bugle Member, Keating Formation, 9 Spathognathodontiform, 13 Keating Formation, 3, 8, 9, 13, 17, 18 Escabrosa Limestone, 16 Spathognathodus cf. S. cristulus, 17 Bugle Member, 3, 8, 9, 17, 18, 19 Hachita Formation, 17 spp., 17 Witch Member, 3, 8, 9, 10, 17, 19 Paradise Formation, 17 Spinoendothyrids, 18 Kelly Limestone, 2 Orogrande Basin, N.Mex., 22 stabilis, Bispathodus, 13 keokuk, Werriea, 13 Osagia, 19 Stacheeins, 18 Klondike Hills, N.Mex., 5, 8, 9, 10, 11, 14, 15, 18, Ozarkodiniform, 17 Stelechophyllum lochmanae, 9 19 microstylum, 9, 18 p Stratigraphy, 4 L Streptognathodus, 14 Packstone, 9, 10, 11, 13, 14, 15, 16, 17, 18, 22 parvus, 14 Lake Valley, N.Mex., 1, 2 Palaeospiroplectammina, 18 Stromatolites, 19 Lake Valley Formation, 1, 8, 16 Paleotectonics, 1, 3, 19 Escabrosa Limestone, 16 Andrecito Member, 10 Papago Indian Reservation, Ariz., 8 subcardiiformis, Brachythyris, 13 Tierra Blanca Member, 13 Paraconformities, 17, 18, 24 subcuspidatus, Syringothyris, 13 Lake Valley Limestone, 16 Paradise, Ariz., 3, 13 Superior, Ariz., 16 Lambdagnathus, 14 Paradise Formation, 2, 3, 8, /3, 17, 19, 22, 24 symmetricus, Gnathodus bassleri, 14 LasCiucesFormation,2, 8,18,24 parvus, Streptognathodus, 14 Synprioniodiniform, 17 lautus, Adetognathus, 14 Pedregosa Mountains, Ariz.-N.Mex., 8, 9, 10, 11, Syringopora, 17 Lepidodendron, 14 14, 17, 19 Syringothyris subcuspidatus, 13 obovatum, 14 Pe/aslwpora, 18 Ligonodiniform, 17 Peloids, 18, 19, 22 T Limestone, 8, 9, 10, 11, 13, 14, 16, 24 Bugle Member, Keating Formation, 17 Lithofacies, 19 Escabrosa Limestone, 16 teres, Rylstonia, 9 lochmanae, Stelechophyllum, 9 Paradise Formation, 13 "Terra Rossa" shale, 8 Lonchodiniform, 17 Witch Member, Keating Formation, 10, 17 texanus, Gnathodus, 15, 17 loxus, Neoprioniodus, 15 Peloncillo Mountains, N.Mex., 8, 13 Tierra Blanca Member, Lake Valley Formation, 13 Percha Shale, 9 Tombstone, Ariz., 24 M Box Member, 8, 18 Tombstone Hills, Ariz.-N.Mex. 8, 13, 17, 18 perfilosum, Mitorthoceras, 13 Toumayellids, 18 macra, Eoendothyranopsis, 19 Petrography, see Analyses Transgressions, 8, 16, 19, 22 Magdalena Group, 8 Planoarchaediscus, 19 Trucial Coast, Persian Gulf, 19 Magdalena mining district, N.Mex., 2 Planopirodiscus, 19 tuberculata, Tuberendothyra, 18 Martin Formation, 8, 16, 18 Plants, 14 Tuberendothyra, 18 Masloviporidium, 19 Polygnathus communis, 13, 17 safonovae, 18 Mexico, 13 communis, 13 tuberculata, 18 Michelinoceras? spp., 13 Priscella, 18 Microfacies, 1, 5, 16 Pseudomorphs, 9, 17 u.v Micropaleontology, 1 microstylum, Stelechophyllum, 9, 18 Q,R Unconformities, 16 Millerella, 19 unicornis, Cavusgnathus, 14 milleri, Hibbardella, 15 Quartz, 8, 10, 14, 15, 17,18,24 U.S. National Museum, Wash., 1 Miogeosyncline, 13 Quasiarchaediscus spp., 14 Vekol Mountains, Ariz.-N.Mex., 8, 15, 16, 17, 18 Mississippi Valley, 14 Rancheria Formation, 2, 8, 16, 22 Vinton Canyon, Tex., 5 Mitorthoceras perfilosum, 13 Read, C.B., quoted, 14 Mogollon Rim, Ariz., 15 Rectoseptaglomospiranella, 18 w.z Mollusks, Paradise Formation, 15 Repetski, J.E., quoted, 13, 17 Montana, 18 Reticycloceras spp., 13 Wackestone, 9, 10, 13, 14, 16, 17, 18,22 Mudstone, 10, 13, 14, 16, 17, 18, 22, 24 Rhachistognathus, 14, 15 Waterman Mountains, Ariz.-N.Mex., 8, 16, 17, 18 Mule Mountains, Ariz.-N.Mex., 8, 13, 16, 17, 18, Rio Grande, 2 Werriea keokuk, 13 19,24 Rylstonia cf. R. teres, 9 Whetstone Mountains, Ariz.-N.Mex., 8, 13, 16, 17, 18 N s Witch Member, Keating Formation, 3, 8, 9, 17, 19 Wyoming, 18 Nautiloids, 13 Sacramento Mountains, N.Mex., 2, 16, 17, 19, 22 Zellerinella, 19 Neoarchaediscus, 19 safonovae, Tuberendothyra, 18 Zuni-Defiance uplift, 22

40 Mississippian (Lower Carboniferous) Biostratigraphy, Facies, and Microfossils, Pedregosa Basin, Arizona and New Mexico

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