nr'rx' ii”: l | l u q: ‘ . at", "€fo @1133 «an ,. V f“: I “ U1” n“. ‘t Mi. l ‘ MI“ ‘ :5. 0 i- L U ’V 3" :y v‘: .1 S for a U of M. rv . u . . . . . \ \ l‘ t "I “I . . . . ‘ t . » . t a : 2 ” O P , » w 5 R f ‘ —---——-——-«-asl MIMIHHIIHHllUllflfllil!HIINHIIWUlLlIIBIHHM 3 1293 10474 850 THESL‘: LIBRARY ‘ . MIChigan State University PLACE IN RETURN BOX to remove this checkout from your record. TO AVOID FINES return on or before date due. MAY BE RECALLED with earlier due date if requested. DATE DUE DATE DUE DATE DUE 2/05 mlCIRC/DateDueJndd-sz ABSTRACT REGIONAL STUDY OF THE PERMO-PENNSYLVANIAN STRATA OF SOUTH DAKOTA By Michael William Barratt The Permo-Pennsylvanian Minnelusa Formation in the state of South Dakota is represented by an accumulation of sandstones, dolomites, limestones, and some evaporites, resting unconformably on Mississippian rocks in the western part of the state. The Minnelusa rests on progressively older rocks eastwardly to finally rest on Precambrian rocks. Lying above the Minnelusa Formation unconformably is the Permian Opeche Shale. Minnelusa sediments were laid down in a predominately marine environment and can be divided into three gross lithologic units. The lower unit consists of a basal sandstone (Bell), a middle cherty limestone, and an upper interbedded cherty carbonate and red shale. The middle unit is predominantly sandstone and carbonate with a few thin, black shales. The uppermost Minnelusa member is largely sandstone, dolomite and anhydrite. Michael William Barratt The eastern limit of the Minnelusa Formation divides the state approximately in half with the zero line re— flecting the basement structure of the Sioux Uplift. The Minnelusa depositional conditions were con- trolled by two marine advances; one during Des Moines time and the other during lower Permian time. Information was obtained chiefly from electric and lithologic logs for determining the thickness, lateral extent, lithology and distribution of the Minnelusa. There are abundant petroleum occurrences in the Minnelusa sediments of the Powder River Basin of Wyoming. South Dakota has numerous oil shows in the Minnelusa and some production in the Barker Dome field south of the Black Hills. This makes South Dakota an interesting possi- bility for further oil production as more wells are drilled to the Minnelusa and more detailed sub-surface studies are made. REGIONAL STUDY OF THE PERMO—PENNSYLVANIAN STRATA OF SOUTH DAKOTA By Michael William Barratt A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Geology 1969 ACKNOWLEDGMENTS Grateful acknowledgment is made by the writer to Dr. James H. Fisher for furnishing numerous logs and maps and other data along with his invaluable assistance, help and enlightenment given during the investigation. The writer would also like to thank Dr. C. E. Prouty and Dr. A. T. Cross for their criticisms and suggestions. 11 TABLE OF CONTENTS ACKNOWLEDGMENTS . LIST OF FIGURES . LIST OF PLATES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 11 v vi INTRODUCTION 0 O O I O O O O O O I O 1 Purpose of the Investigation. Method of the Investigation . Previous Work. . . Location and Topography . . . . Recent Petroleum Exploration. STRUCTURE . . . . BlaCk Hills 0 O Lemmon Syncline . The Sioux Uplift. Chadron Dome . STRATIGRAPHY . . Nomenclature . . . . . O . . . . . . 0 . . . . . . O . . . . . O . . . . . Age and General Correlation . Description and Correlation of Mississippian Sediments . . . . . . . O . . . . . . . . . . . . . O . . . . . . . . . . . . O . . . . . . . . . . . . O . . . . . . . DESCRIPTION AND ORIGIN OF PERMO—PENNSYLVANIAN SEDIMENTS . . . . Minnelusa Formation. Opeche Formation. . Minnekahta Formation Goose Egg Formation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Petroleum Possibilities in the Minnelusa. . . . . . . O . . . . . . . . . . . . . 1 1 5 6 7 lO 10 13 15 15 l7 17 19 23 28 28 39 “O “l 43 iii CONCLUSIONS . REFERENCES APPENDIX . 0 . . o . . o . . o . . o . . o . . o . . o . . o . . o . . o . . o . Page U5 147 5“ iv LIST OF FIGURES Figure Page l. Petroleum Drilling Activity in South Dakota Since 1960 . . . . . . . Major Structural Feature Locatioanap North-south Cross—section from NW Nebraska to SE Montana Correlation Chart . . . . . . . . . . . . . Graphic Columnar Section of the Minnelusa Formation of South Dakota . Panel Diagram of the Minnelusa Formation from Laramie Mountains to Black Hills Eastern Limits of Mississippain Units in South Dakota. . . . . . . . . Pre-Pennsylvanian Paleogeologic Map . Paleogeographic Map During Early Des Moinesian Time . . . . . . 10. Paleogeographic Map During Late Des Moinesian Time . . . . . . . . . . ll. Peleogeographic Map During Missourian Time 0 I O O O O O O O O O l2. Paleogeographic Map During Virgilian Time 0 O O O O O O I O O O 13. Paleogeographic Map During Wolfcampian Time 0 O O O 0 O O 0 O O O 11 14 2O 22 2A 27 3A 36 36 37 37 38 LIST OF PLATES (In Pocket) Plate I. Structure Contour Map II. Isopach Map of the Minnelusa Formation III. Carbonate-Evaporite Ratio Map of the Minnelusa Formation IV. Sandstone Percentage Map of the Minnelusa Formation V. Lithologic Column Map of the Minnelusa Formation VI. Graphical Representation of the Lithology of the Minnelusa Formation VII. Isopach Map of the Opeche Formation VIII. Electric Log Cross Sections (2 sheets) vi INTRODUCTION Purpose of the Investigation South Dakota has never been a particularly active area for petroleum exploration. There are less than 600 test wells for petroleum in the entire state. This fact, coupled with the lack of exposure of the older rock section in areas outside the Black Hills, has made it difficult to unravel the stratigraphy and sedimentation of South Dakota. The Permo-Pennsylvanian Minnelusa Formation is a prolific producer of petroleum in the eastern portion of Wyoming. This study is an attempt to establish reliable correlations of the Minnelusa in South Dakota, to deter- mine the environments of the various sedimentary units, and to relate these factors to the possible occurrence of petroleum in South Dakota. Method of the Investigation Electric logs from 109 oil and water wells were used to determine the extent, thickness and general character of the Minnelusa Formation. Lithologic logs from A6 oil tests were used to determine and verify the lithology and thickness of the Minnelusa. Several gamma ray-neutron logs were also available and proved valuable in picking and correlating formation tOps. Accompanying the logs were approximately 200 commercial and company scout tickets. A total of 19“ wells in South Dakota were found to be of value as control points. Control point density varied widely. Near the Black Hills and Buffalo Field, numerous wells within a township were available. In other areas south and north of the Black Hills, con- trol proved adequate for the investigation being made. Eastward from the Black Hills, the number of test wells decreases rapidly. Control points were so widely spaced that one well per twenty townships was available in several areas of the south-central and northeastern part of the state. With electric logs as the main source of infor— mation, a structure contour map was constructed. Litho- logic logs provided information for the construction of the sandstone percentage, carbonate ratio, lithologic. column maps and the graphical representation of lithology. It should be mentioned here that several companies pub- lish and release electric logs and lithologic logs with the formational tops already picked. Although these logs are correlated and the tops picked by geologists, they lack the accuracy required in a detailed study of a region. The turnover in company personnel involved in picking these tops causes considerable confusion as to which criteria each particular geologist used to determine his pick. Because one man may not agree with another on the criteria used in choosing a formation top, a considerable number of wells in South Dakota were found to be in error. The South Dakota Geological Survey apparently accepts these commerical top picks as being valid, because their publications agreed essentially with the commercial tops. In this study it was soon learned that tops selected by commercial studies and South Dakota Geological Survey publications had to be re- evaluated. V A number of writers, using commercial top selections and state publications, presented papers involving areas surrounding and including South Dakota. It was evident that throughout the literature concerning South Dakota and areas around it, commercial top picks were accepted. The writer has re-evaluated these wells and has picked tops uniformly to construct the electric log cross-sections. The distinctive pattern on the resistivity curve shown by the overlying Opeche and Minnekahta Formations was generally used as a reference point for preliminary correlations. A good example of this pattern can be seen on well number A—l in the electric log cross—section (Plate VIII). After this pattern was recognized, it was relatively easy to find the top of the Minnelusa. A problem developed with the determination of the thickness of the Minnelusa south and southwest of the Black Hills area because most of the oil tests in this area penetrated the Minnelusa but did not go completely through it. Publications and company scout tickets were used in determining the thickness in these areas. Dur— ing the course of well correlation, special care was necessary when correlating wells near the truncation on Precambrian rocks becaEse the Opeche-Minnekahta resis- tivity pattern could become confused with that of the Minnelusa. Below the Minnelusa, Mississippian rocks which are unconformable at the Pennsylvanian-Mississippian contact, were readily determined on the basis of a charac- teristic resistivity high. Webster (1963), in his paper, recommends an article by Stratton and Ford (19A9) as a "primer" in log inter- pretation and this writer also agrees that the article "stands out in clarity and simplicity without sacrificing accuracy." It was used as a basis to interpret and cor— relate the well logs. Because the Minnelusa is composed of sandstones, dolomites, limestones, shales and evaporites, the above reference proved to be valuable since problems on lithic interpretations did arise. Foster (1958) states that the most useful curves for correlation of the Minnelusa in the Powder River Basin are the gamma ray and resistivity curves. Since several wells in the Powder River Basin were examined by the writer to facilitate correlation south and north of the Black Hills, Foster's recommendation was followed and proved true in South Dakota. Radioactivity logs were especially helpful in positive correlation of the Minnelusa where no electric logs were available. Electric and radioactive logs can be used to correlate wells adequately in the Pennsylvanian, provided the wells are not too far apart. Using principles found in Stratton and Ford (19A9), Foster (1958) and from personal communications, the writer was able to work out, to his own satisfaction, the well correlation phase of this investigation. Previous Work The literature dealing with the Minnelusa Formation in South Dakota has been concerned principally with the Black Hills area and the western bordering states of Wyoming and Montana. Works of a regional nature, concerning the Minne- lusa, including studies of larger areas than the state can be found in Darton (1901), Darton and Paige (1925), Brady (1931), Condra and Reed (1935, 1940), Ballard (19A2), Baker (1951), Barnes (1952), Gries (1952), Noble (1952), Agatston (195A), Bates (1955), Foster (1958), Tranter and Petter (1963), and Tenny (1966). Up to the present time, there has been no study of the Minnelusa published which is as detailed as the pre— sent study. Location and Topography The state of South Dakota, occupying an area of 77,615 square miles, lies in the northern Great Plains region. It can be divided into four main provinces. The Black Hills are a mountainous, much eroded, dome shaped uplift, surrounded by nearly horizontal beds. They are situated along the west central border between South Dakota and Wyoming. The Tertiary table lands are found west of the Missouri River. They are remnants of Tertiary beds differentially eroded by streams. Impermeable clay and shales, sparse vegetation, and sudden rainfall have all played a role in shaping these table lands and the bad- land topography along the White River in southwestern South Dakota. The glacial province occupies the eastern half of the state. Here the typical features caused by glaciation such as moraines, kettle lakes, and till plains are found. The glacial terrain is interrupted on the border of Minnesota and South Dakota by the Sioux Uplift. The Sioux Uplift is a quartzite remnant exposed in the southeastern corner of the state. The quartzite lies on a granitic basement complex. Recent Petroleum Exploration Webster (1963) adequately covers the period of petroleum exploration between initial discovery and 1960. Figure 1 shows the drilling activity since 1960 in the state. At the present time, the state of South Dakota has only one commercial oil field-—the Buffalo Field located northwest of Buffalo in Harding County. This field produces oil from the Ordovician Red River Lime— stone at about 8000 feet. Several other non-commercial discoveries have been exploited, the most interesting of which is the Barker Dome Field in Custer County. Oil has been known to exist around the south end of the Black Hills since 1913. Many of the wells were oil tests, but there were also a number of dry holes too shallow to yield much geological data. During the period between 1929 and 1930, several good shows were obtained from the Minnelusa Formation. The First Leo Sand near the top of the formation yielded many of these shows. Non-commercial oil was found at Barker Dome (sec. 34, T. 63., R. 2E., Custer County) in 1929. Several unsuccessful tests were drilled before L. A. Helms completed the Number 1 Coff- ing as a producing well in 1955. The production here was probably due to variations in permeability within the producing zone. Faulting also has been suggested as an explanation (Gries, 196A). Oil was obtained from a thin sand member (Leo) directly above a radioactive shale near é nun-n or txnoruronv 1131’s DRILLED s c . L L U B s n r u w o m A T A D 0 6 9 I E C N I S A T O K A D H T U O S N I Y T I V I T C A G N I L L I R D M U E L O R T E P = I E R U G I F R A E Y ‘ 7 6 ' 6 6 ' 1 : 6 ' . 0 6 9 4 6 ' 3 6 ' CI 2 6 ' the top of the Minnelusa at depths between 1391 and 1392 1/2 feet (Gries, 1964). Oil recovered from this field shows an API gravity of 30 degrees and is black in color. Further tests have been discouraging. Total oil production in the state averaged 650 barrels per day between 1963—1967. During this same period, 8A oil tests were drilled in South Dakota. All of them were unsuccessful. There remains approximately 25,000 square miles of undrilled, untested land that could prove favorable for oil accumulation within the Minnelusa Formation. Oil prospects in the state look dim, but because so much of the state remains untested, some pools could possibly be found. Preparation of detailed studies such as this could prove to be of some value. Numerous types of traps exist in the Minnelusa in Wyoming to the west. Looking for stratigraphic traps, porosity traps, and fault traps seems to be the best course when exploring for oil in the Minnelusa in South Dakota. STRUCTURE Figure 2 shows the major structural features in and around the state of South Dakota. The Black Hills, the Lemmon Syncline, the Sioux Uplift and the Chadron Dome are the most important ones. Black Hills The major structure in the southwest part of the state is the Black Hills. This can be seen as a domal shaped "island" rising out of the plain of western South Dakota and eastern Wyoming. The Black Hills, the eastern- most part of the Rocky Mountains, have an elliptical shape, 120 miles by 60 miles. A Precambrian core of highly folded schists invaded by granite in the southern part of the Black Hills, trends nearly north-south and is flanked by upturned Paleozoic and Mesozoic strata. Lara- mide plutons intrude the core in the northern portion. The uplift trends and pitches northwest beyond the crystalline zone. The east flank is fairly steep, up to A5 degrees, the broad top is flat, and the west flank is gentle, less than 20 degrees. Adjacent to the central Precambrian core is a plateau area in the west central 10 G SIOUX SOU TH DAKOTA I HARTVILLE umr‘r I M O Y W A. O 04P0 4' NEBRASKA a ‘9’ y / / Dauvn- NEE; ”gm 7/ any?“ a Aél N / / \II' / / ‘ / JU/LESéURG CENTRALK 1%" SALINA 5 ° I FIGJRE 23 . MAJOR STRUCTURAL FEATURE LOCATION MAP MODIFIED snow wassrzn VIA usms ‘ UPLIFT8 12 part formed by Paleozoic limestones not yet stripped from the Precambrian rocks. Surrounding the uplift area be- yond the plateau is a continuous strike-valley eroded in Jurassic and Triassic strata. This is commonly called the "Racetrack" or Red Valley because of the red Triassic Spearfish shales that principally underlie it. Completing the structure of the Black Hills are inward facing hogbacks held up by the Fall River and Lakota sandstones of Cretaceous age. To the west of the Black Hills lies the Powder River Basin which contains about 16,000 feet of sedi- mentary rocks. Darton estimates the strata were uplifted 9,000 feet in the Black Hills, so the structural relief between the bottom of the Powder River Basin and the top of the Black Hills is about 25,000 feet. The age of the uplift can only be approximated be- cause of the lack of Paleocene or Eocene overlaps in close proximity to the uplift. The Laramide age deposits that might have been derived from the Black Hills are now in surrounding areas and separated from the uplift by a Cretaceous belt of outcrops. The doming could have started in latest Cretaceous time with the deposition of the Fox Hills and Lance beds in the Powder River Basin. The southern margin of the Black Hills contains two discernible anticlines. On the southeast, the Chilson Anticline and on the southwest the Cottonwood Creek 13 Anticline. These can be seen on the structure contour map (Plate I). Oil tests on these structures have so far yielded no commercial oil. Figure 3 shows a north- south cross—section of the Black Hills. Lemmon Syncline A basin extending into the north-central part of South Dakota is called the Lemmon Syncline. This is con— sidered to be the South Dakota portion of the Williston Basin by most geologists. The Williston Basin is thought to have its origin in Precambrian time, existing through Paleozoic and Mesozoic time (Pye, 1953). The general shape of the Williston Basin with its southern extension give us some clue to the tectonics in the state. The Williston Basin is situated between the Cordilleran Geosyncline on the west and the Canadian Shield area on the east. During the Laramide Orogeny, between late Cretaceous and early Tertiary time, an eastward thrust was exerted on the beds in western United States. The thrust from the west, created the asymmetry of the Black Hills and the Williston Basin. The Lemmon Syncline is asymmetrical to the west as shown in the structure contour map (Plate I). The Williston Basin is an important producer of petroleum, with most of the oil coming from the Paleozoic section. 2H a n o a o v i o x v g ( 3 ’ 8 ! ) O U V T ‘ I V G 8 3 1 “ V N V I N O W ' 3 8 0 . 1 . \ V M S V U B B N ' M N N O E L - I N O L L O B S S S O B O H U I O S - H J . U O N I E 3 8 0 9 b ! m o m \\ V X S V U S B N l 9 1 2 ° . 1 3 0 0 0 1 . H ( ~ " \ — — — - ' q u v I ’ 1 9 9 ‘ 15 The Sioux Uplift The Sioux Uplift occupies a portion of the south- eastern part of the state as well as a small part of southwestern Minnesota. It is composed of a quartzite remnant overlying a granitic basement complex, both of which are Precambrian. The Sioux Uplift is a topo- graphic as well as a structural feature. One may wonder why this particular remnant exists. The Sioux Quartzite was considerably more widespread in Precambrian time than it is now. Emerging about mid-Ordovician time (Baker, 1951), the quartzite was eroded down except for those areas with synclinal structure. In the subsurface, the Sioux Uplift extends westward in South Dakota to the vicinity of Pierre. It is thought to be a part of the old Transcontinental Arch which had its beginning in early Paleozoic time (Eardley, 1951). Chadron Dome The bulbous extension of the northwestern end of the Chadron Arch is called the Chadron Dome. The northern portion of the dome can be seen on the structure contour map (Plate I), in the southwestern part of the state. The Chadron Dome was uplifted during Early Pennsylvanian time (Atoka) along with the Central Kansas Arch. The Laramide Revolution subjected it to further uplift. Another structure which should be mentioned is the northwest-southeast trending fault northeast of the 16 Black Hills. It was based upon the information obtained from the two wells drilled by Mobil. They are the Sipila Number Fll-IAP located in NW 1/A, NW 1/4 of section 14, T. 9N., R. 8E. and the Mickelson Number 1 located in NE 1/4, NE 1/A of section 7, T. 9N., R. 9E. as shown on Plate I. Because of the proximity and general trend of this fault to the fault zone lying on the southeastern side of the Cedar Creek Anticline, it is possible that a fault zone trending from the Cedar Creek Anticline, through South Dakota could exist. Pye (1953) believes that the defor- mation of the Cedar Creek Anticline occurred in late Devonian or pre—Mississippian time. STRATIGRAPHY Nomenclature The history of nomenclature of Permo-Pennsylvanian rocks in South Dakota and the surrounding regions is a very complex problem because of the fact that three main sets of names exist in Wyoming and South Dakota. Darton, working in the Bighorn Mountains in north-central Wyoming during the early 1900's postulated a twofold division within the Pennsylvanian beds. The lower beds were re- ferred to as Amsden and the upper ones were called Tensleep. Later, Darton and Paige (1925) formulated a nomenclature system within the Black Hills area. Here, the name Minnelusa, as applied by Winchell (1875L was accepted as the Pennsylvanian system. A correlation was attempted between the Bighorn classification and the Hartville Up- lift area when Condra and Reed (1935) described the Hart- ville Formation and then sub-divided it into divisions. This classification was then correlated with the Black Hills area by Condra and Scherey (1940) and Condra and Reed (19A0). A rough correlation was attained but the Hartville classification never became popular. 17 18 This paper uses the classification system proposed by Darton in the Black Hills area; the writer has extended it eastward through the state. The name Minnelusa, (Sioux for rapid water), was applied by N. H. Winchell in 1875 to a series of white crystalline sandstones, anhydrites, shales and limestones in the Black Hills area. The section is well exposed west of Rapid City. Darton and Paige (1925) reported that G. H. Girty had identified fusulinids from the medial beds of Minnelusa in the Black Hills. Later investigations of the Minnelusa near the Black Hills and surrounding areas, especially the Hartville Uplift area, disclosed that accurate correlation could be obtained with the use of fusulinids. Dille (1930), in his work in the southern part of the state, concluded that the base of the Minnelusa beds were equivalent to the "Des Moines stage of the Carboni- ferous." He based this on "Fusulina cf. cylindirica" which he found in the basal red shales of the Minnelusa in Custer County. Roth (1930), working in the same region as Dille, identified Fusulinella euthusepta? from approximately 100 feet above the base of the formation, which places it in the Cherokee (Upper Atoka—Lower Des Moines). He divided the Minnelusa into two units: the lower, correlating with the Amsden and the upper, correlating with the l9 Tensleep. He considered the upper Minnelusa to be Missourian and upper Des Moines in age on the basis of Tensleep correlations in the Bighorn Basin. The Tensleep— Amsden contact problem in Wyoming bears directly on the correlation of the upper and lower Minnelusa near the Black Hills area. This contact, discussed by Fisher (1963), is still sometimes difficult to establish, but it is generally agreed that the contact is between Atoka and Des Moines strata. Figure A shows the correlation chart (Bates, 1955; Tranter and Petter, 1963; and Tenny, 1966). Age and General Correlation The Minnelusa Formation was once thought to be Pennsylvanian in age, but is now considered to be Permo— Pennsylvanian. However, determining and correlating the upper and lower boundaries has remained a problem. The name Minnelusa is now generally applied throughout the entire state of South Dakota, north to the Nesson Anti- cline and westward through the eastern half of the Powder River Basin. The term "Minnelusa sandstone" is errone- ously used because the formation contains numerous car- bonates and evaporites as well as sandstone. Primary age correlations have been made from the Eastern Powder River Basin in Wyoming to the Black Hills area. On the basis of fusulinids, the lower and middle 20 v v v v ‘ v ZZUJ R E P P U M _ J . T J T v — ‘ A A A V ‘ v ' v ' v ' A A A v v — “ " v v v v v v A A A A A A A A A A . 1 L R E L Y T R E W O L A A A A A P R E W O L O T ” L I L J I L L L E B v ' w v ' v y v A A A A v N E D Y A H I I T R A H C N O I T A L E R R O C : 4 E R U G I F A S U L E N N I M N E D S M A J I . R E P P U A S S A C ' v ' v v ; . . . 1 3 R E V O K E K I O-_I> .J >' m z 2 III ¢ .'~ '1', —-. in"-' .r I... “ -=I;. FIGURE 5: GRAPHIC COLUMNAR SECTION OF THE MINNELUSA FORMATION OF SOUTH DAKOTA MODIFIED FROM WEBSTER (IOOBI 23 Figure 6 shows a panel diagram correlating the Black Hills and Laramie Mountains. Description and Correlation of Mississippian Sediments Mississippian rocks in the state of South Dakota unconformably underlie the Minnelusa Formation because of post-Chesterian—-pre-Pennsylvanian erosion. They COHSiSt of a lower Madison Group, and an upper Big Snowy Group. The term Madison is used to include the Lodgepole, Mission Canyon and Charles Formations. Laudon and Severson (1953) concluded, on crinoid fossil data that the Lodgepole and Mission Canyon Formations represent continuous uninter— rupted marine deposition during Kinderhookian and early Osagian time. The Charles Formation was named by Seager (19A2) and has the type section in Garfield County, Mon- tana. The formation is composed of dense dolomites, lime- stones and some evaporites. It is considered to be Meramecan in age. The Mississippian outcrop of the Black~ Hills is known as the Pahasapa Formation and was named by Jagger in 1901. This formation consists of a carbonate series up to 630 feet in thickness. It overlies the Englewood unconformably and is well exposed in the Black Hills area. The formational name is usually confined to the Black Hills area. The term Mission Canyon is usually considered correlative with the Pahasapa, and is used in the subsurface in the Williston Basin-Lemmon Syncline areas. 2A L . S T M E I M A R A K E E R C E C N A L T E E F 0 ' ° 3 3 ” " N O I T A R E G G A X E - T R E V X 8 6 - R E K R A M D E R — M R - — A I C C E R B — . m D E N I L R E D N U S I E P Y T K C O R T N A N I M O D S L L I H K C A L B O T S N I A T N U O M E I M A R A L M O R F N O I T A M R O F A S U L E N N I M E H T F O M A R G A I D L E N A P ! 6 E R U G I F ) 5 5 9 0 S E T A B M O R F 25 The Big Snowy Group of Chesterian age overlies the Madison Group in northwestern South Dakota. It consists of, in ascending order, the Kibbey, Otter and Heath Formations, a series of elastics and non-clastics lying in central Montana and the Williston Basin. The Kibbey Formation is the only one that extends far enough south into South Dakota to unconformably underlie the Minnelusa there. Agaston (195A), reporting the effects of pre- Pennsylvanian erosion on the Mississippian surface in northern and eastern Wyoming, stated that channel fills, 5-35 feet thick, commonly contain blocks of limestone and chert in a quartz sand. Overlying the Mississippian carbonates in other areas of Wyoming and South Dakota are the Amsden, Minne- lusa and Hartville Formations. These three are generally correlative, but in Montana lowermost Amsden is thought to be of Mississippian age. The thickness of the Madison Group in eastern Wyoming and South Dakota shows great variations mostly due to pre- Pennsylvanian truncation. The lithology of the Madison in this area is mostly dolomitic limestone grading westward into a rather pure limestone. The sedimentation pattern of the Madison consists of carbonate sequences with inter- bedded evaporite cycles. The Mission Canyon Formation along with an overlying evaporite unit of the basal Charles Formation form the medial beds of the Madison Group. The I 20 Mission Canyon Formation exhibits two evaporite cycles. The lower one, at the base of the formation is repre- sented by a minor evaporite development. The upper evaporite unit of the Mission Canyon is overlain by the basal Charles evaporites. A Mississippian exposure in Spearfish Canyon (T. 6N., R. 2E.) is the same lithologi- cally as the subsurface with the exception of the develop- ment of minor limestones in the lower evaporite cycle. Late Madison sedimentation is represented by the Charles Formation. The formation consists of a lower evaporite cycle overlain by marine carbonates. The evaporite cycle is not as pronounced as that in the Mission Canyon. Primary carbonates represent intense saline conditions in southeastern Wyoming and solution- breccias are developed in outcrops of the evaporite zone. The upper contact of the Charles is easily recognizable where it is overlain by Big Snowy and Pennsylvanian Amsden or Minnelusa sediments because they are composed mostly of sand and shales, in marked contrast to the Madison Group carbonates. The lithology of the Charles Formation in northeastern Wyoming is dominantly dolomite with inter- bedded limestones and evaporites. North of the Black Hills the limestone and dolomite proportions show wide variations. The Madison Group in South Dakota shows a variety of lithologies, but consists chiefly of carbonates. Figure 7 shows the eastern limits of Mississippian units. 27 ) 4 6 9 “ N O S L E K C I M O S E I R G M O R F D E I F I D O M S T I N U N A I P P I S S I S S I M F O S T I M I L N R E T S A E 2 7 A T O K A D H T U O S N I E R U G I F \ D 9 ” ' I / " E H T F O E N I L 0 $ o / ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ O” " 5 — — — . _ _ ' . , _ _ . . _ _ _ _ \ - ‘ / ’ , / O 0 L E H T F O T I M I L , ‘ $ / / $ & 9 / . l l . / / " r ’ I / l , I l DESCRIPTION AND ORIGIN OF PERMO— PENNSYLVANIAN SEDIMENTS Minnelusa Formation A general lithologic description of the Minnelusa shows that in surface outcrOps around the Black Hills, it contains numerous beds of breccia, although the number and thickness of these beds vary locally. Gypsum beds sometimes appear in surface outcrOps, but these are relatively uncommon due to solution and leaching of these beds. The Minnelusa thickens rapidly toward the southwest because the Lusk Embayment was being filled with increasing thicknesses of limestone—shale sequences during lower Minnelusa time. Another factor accounting for marked thickening in the subsurface is the appearance of thick anhydrite beds which are represented on the outcrop by thin collapse breccias in the southwestern Black Hills. We can see then that the Black Hills lithology represents a leached and thinned formation which is more fully developed to the southwest. The question of age correlation of the Minnelusa Formation in South Dakota is a problem. The lower limit of the formation is not a major problem because of the marked unconformity between Mississippian and lower 28 29 Pennsylvanian sediments. The contact generally was easy to pick. The problem of calling Minnelusa only Pennsyl- vanian in age existed before Bates (1955) suggested that surface upper Minnelusa was, in general, correlative to a subsurface upper evaporite zone. This was thought to correlate with Upper Hartville in Wyoming which Love, Henbest and Denson (1953) consider to be Wolfcampian in age. It is now generally agreed that upper Minnelusa is Wolfcampian in age based on fusulinid evidence and lithic correlations. Fossils in the Minnelusa Formation are somewhat rare, but fusulinids in the Black Hills area have been found and dated generally as Desmoinesian. The upper limey beds near Hot Springs have shown a few Composita sp. and Spirifer sp. found by G. H. Girty (Darton and Paige, 1925). Sedimentary structures within the Minnelusa Show cross-bedding (Darton and Paige, 1925) in upper and middle members. The type section of the Minnelusa as measured and described by Brady (1958), is given in the Appendix. The thickness of the Minnelusa Formation in South Dakota ranges from zero to 1200 feet as shown in Plate II, the iSOpach map. The formation is absent in the eastern half of the state. It thickens toward the north- west but then thins to A00 feet in the northwestern part of the state. The Minnelusa thickens also to the southwest 30 where, just southwest of the Black Hills, it reaches its maximum thickness. A very interesting ridge and valley effect is exhibited south of the Black Hills. A signifi- cant pattern also is developed in the northwestern part of the state. Where the Opeche was laid down on top of a post—Wolfcampian erosional surface and because the Opeche-Minnekahta contact is conformable, thickness vari- ations within the Opeche are due to the erosional surface. As can be seen on a comparison of Plate II and Plate VII, the Opeche is thin where the Minnelusa is thicker. This can be seen particularly well in the northwestern portion of the state. Plate III, a carbonate-evaporite ratio map, was included in the study to ascertain the location and relative position of carbonates, chiefly dolomites and limestone, within the Minnelusa Formation. This map, used in conjunction with the iSOpach map, demonstrates that the Minnelusa Formation had considerable thicknesses of carbonates located in the west-central portion of the state. Another relatively high carbonate-evaporite con- centration is shown in the north-central part of the state. In order to determine the location of principle source areas of coarse clastics, a sandstone percentage map was constructed (Plate IV). An accumulation of sands in the northwestern and southwestern portions of the state suggest proximity to source areas. The pattern of sand 31 accumulation shows that the initial source areas probably were separate as opposed to one great source. The southern accumulation was probably due to activity in the Chadron Arch area. This area was tectonically active throughout Pennsylvanian time. The northern accumulation was caused by an uplifting of the Central Montana Uplift during late Pennsylvanian time. This furnished coarse clastics to the south and southeast. For the purpose of completeness, an isopach map of the Opeche Formation was drawn (Plate VII). A problem has existed as to whether the Opeche was conformable where it overlies the Minnelusa. Darton (1901) suggested that an uplift occurred after Minnelusa time, but did not imply any significant erosion. He concluded that the Minnelusa- Opeche contact is conformable. Brady (1931) also concluded the same thing in the Beulah, Wyoming district. Later, as more drilling was done in Wyoming and South Dakota, the contact was interpreted as unconformable. Post—Wolfcamp time in the Black Hills was a time of erosion. To show that the Opeche—MinneluSa contact is unconformable is somewhat difficult because of lack of exposures. The outcrOp thickness of the Opeche ranges from 52 to 109 feet and the subsurface thickness increases in the southwestern part of the state to over 300 feet. Three possibilities for an explanation of the surface and subsurface thickness differences in the Opeche exist. The 32 -_ ; A . first explanation postulates that a flat base but an irregular top exists in the Opeche. This can be ruled out because of the regular contact between the Opeche and the overlying Minnekahta. The possibility of the Opeche having both an irregular top and base can be dis- missed for the same reason. This leaves the possible explanation of the Opeche having an irregular base and a flat top. According to Stone (1966), the irregularity of the Minnelusa top suggests an area of topographic relief chiefly southwest and northwest of the Black Hills showing the Opeche as a broad channel fill on the Minne- lusa. He states further than channel filling east of the Black Hills is limited because two main channel areas seem to present themselves, the most predominate being from the northwestern portion of the state. This interpre- tation is quite unlikely because it is generally thought that the Opeche is a tongue of the Phosphoria sea. The electric log cross-sections (Plate VIII), are possibly the most valuable tools in this study. They show the general distribution pattern, the thickness and inter- val of the Minnelusa in the state. Since the Minnekahta-Opeche interval can be readily determined, this was used as a "control point." Where this was non-existent or where the interval thinned out so much that the pattern was lost, a typical lower Minnelusa pattern could be used. This lower Minnelusa resistivity 33 pattern could be confused with the Mississippian Kibbey limestone, but careful correlation proved it to be lower Minnelusa. The problem of the depositional environment and source areas of the Minnelusa Formation in South Dakota is still debatable. Because so much work has been done in eastern Wyoming, a number of theories attempting to solve this problem have been postulated. However, east of the Black Hills area, relatively little work has been done to solve the questions of where and how the Minnelusa sediments were deposited. Figure 8, a pre-Pennsylvanian paleogeologic map shows the state at the end of post-Mississippian erosion. Ballard (19A2), believes that the Pennsylvanian was laid down on an eroded Mississippian carbonate sequence with a Precambrian high, extending northeast from the Cambridge Arch to the Sioux Uplift, serving as a source area. Tranter and Petter (1963), approaching the problem from a regional point of view, believed that recurrent uplifts in central Wyoming created cyclic deposition of shale, dolomite and sandstones on the Wyoming shelf area in eastern Wyoming and western South Dakota. ‘Tenny (1966), also working on a regional basis, conceived of a,positive area, the Pathfinder Uplift, in southeastern WyOming furnishing sediments to the west, north, and eastalong with the ancestral Front Range Uplift to the south. The 3A FIGURES: PRE-PENNSYLVANIAN PALEOGEOLOGIC MAP (AFTER ANDRIOHUKJOSS a MAOAULEY, I984) 35 Black Hills area and Chadron Arch area, he thought, were also positive but did not contribute significant sediments in South Dakota. Allen (1966), believes that the Minnelusa sandstones are southeast trending shore line sand dunes with an almost cyclical rise in sea level at the same time that the dunes were being blown onto tidal flats. He also postulated an uplift after Wolfcampian time with subsequent drainage incisions allowing the Opeche Formation to fill in the valleys which were related to the original Minnelusa sandstone build-ups. On the basis of the literature and on the maps and cross-sections which were constructed, the writer believes the following events transpired during the Permo-Pennsyl— vanian time. Following the termination of Mississippian time a general southward tilting of eastern Wyoming and western South Dakota took place. Two seas developed during Morrowan time, one moving northeastward from the Denver-Julesburg Basin, the other transgressing eastward out of the Cordilleran Geosyncline. The series of paleogeographic maps modified from Tranter and Petter (1963) (Figures 9 through 13) show this dia- gramatically. The sea transgressing from the Denver- Julesburg Basin was restricted by the Colorado Mountains, Sioux Uplift and the Cambridge Arch. By the end of Morrowan time, the western half of the state was covered. 36 la 65 3): SEA e° V‘ V O: q: In 2 I. FIGURE 9: PALEOGEOGRAPHIC MAP DURINGVQ EARLY DES MOINESIAN TIME MODIFIED FROM TRANTER a PET‘I'ER (m3) SEA o V$ “J m 3 0) I I3 2 FIGURE IOI PALEOGEOGRAPHIC MAP DURING LATE DES MOINESIAN TIME 37 LAND <‘ SEA ' L FIGUREII'. PALEOGEOGRAPHIC MAP DURING MISSOURIAN TIME MODIFIED FROM TRANTER O PETTER (I963) SEA LAND I J FIGURE IZI PALEOGEOGRAPHIC MAP DURING VIRGILIAN TIME ) 3 6 9 “ R E T T E P a R E T N A R T M O R F D E I F I D O M 38 D N A L R A E N E R O H S A E S _ E M I T N A I P M A C F L O W G N I R U D P A M C I H P A R G O E G O E L A P I S I E R U G I F 39 The sediments deposited were of a normal marine sequence thickening toward the southeastern part of the state into the Lusk Embayment. Early Desmoinesian time saw an uplift of the Colorado Mountains to the southwest. These furnished great quanti- ties of arkose in southeastern Wyoming but quartz sands comprised most of the sediments in South Dakota. The sea was regressing at this time and was relatively shallow. The most likely source area was the Colorado Mountains.r A thickening toward this structure along with an increase in sandstone is shown on the lithologic column map (Plate V). An interfingering relationship exists between the sand and a dolomite, shale lithology. This possibly represents a near shore environment.‘ We also see an interbedding of thin limestones with sandstone beds. This points to periods of marine transgression followed by longer periods of re- gression during late Pennsylvanian time. During these regression periods, tidal flats and beaches were exposed to erosion giving rise to cross—bedded eolian deposits better sorted than the marine sediments. Opeche Formation The Opeche Formation, named by Darton in 1901 is composed of maroon, red, purple and ochre shales and silt- stones with thin beds of brown and white dolomite. In- clusions of anhydrite and gypsum are found in some A0 locations. It lies conformably below the Minnekahta limestone and unconformably above the Minnelusa Formation as discussed earlier. No fossils have been found in the Opeche so its placement in middle Permian is dependent on stratigraphic position. The Opeche is widespread through- out the western half of South Dakota. The thickness varies from a feather edge in the middle of the state to over 300 feet in the southwest. The great changes in thickness are due to its unconformable relationShips with the Minnelusa. The depositional environment of the Opeche shale was that of a transgressing sea. The Wyoming shelf area, at the beginning of Opeche time was tilted to the west and the Phosphoria sea to the west transgressed to the west depositing tongues of limestone and shales. The Opeche and Minnekahta Formations are eastward tongues of the Phosphoria sea. Minnekahta Formation The Minnekahta limestone, which lies conformably above the Opeche and below the Goose Egg is the most extensive deposit of the Phosphoria sea. Lithologically, it can range from a dense, hard limestone to a fine, crystalline dolomite but it generally consists of a very uniform, thin bedded, light pinkish-gray limestone. Some pinpoint porosity does A1 exist in wells near the Black Hills. It-is also somewhat anhydritic throughout the state. The Minnekahta averages A0 feet thick in the Black Hills area. It is also easily recognized in this area as the predominant cliff-former. As a result of the westward tilting of eastern Wyoming, a restricted sea in eastern Wyoming receded towards the west. Coupled with this, a climatic change to a more arid environment allowed the deposition of the Minnekahta to take place along near-shore flood plains, bars and tidal flats. Weller (1956) believes that the Minnekahta was deposited as an inorganic, fine-grained, chemical precipitate. Oolites found in the Minnekahta and the fact that it was deposited along with red beds led him to the above conclusion. However, the writer disagrees with Weller because the Minnekahta shows algal structures in many areas (Fisher, personal communication). Ggose Egg Formation The boundaries and naming of the Goose Egg Formation have been a problem since the early 1900's. In 1901, Darton, working in eastern Wyoming, described a series of redbeds between the Minnekahta limestone and the Jurassic Sundance which he referred to as the Spearfish Formation. The lower portion of these beds was later described by Burk and Thomas in 1956. They proposed the name Goose Egg Formation to include rocks between the Casper Formation A2 of Pennsylvanian age and the Chugwater Formation of Triassic age. Burk and Thomas included the Minnekahta and Opeche beds within the Goose Egg. This relegated them to members, which they are not. It is common practice among writers to refer to the Goose Egg as a formation and the Opeche and Minnekahta as members of that for- mation. If we look at the definition of a member, we can see the problem. According to Weller, members are "compara- tively unimportant and morecn°less local rock units in— cluded within formations." We can see that the Opeche and Minnekahta are certainly not local beds, because they cover most of western South Dakota and portions of three surrounding states. The Minnekahta and Opeche beds were called formations before the name Goose Egg was proposed, so they have priority. The type section of the Goose Egg Formation as described by Burk and Thomas (1956), is located near the Goose Egg Post Office in central Wyoming. This section contains approximately 10 feet of Minnekahta lime- stone and 70 feet of Opeche shale which they identify. This writer proposes that the Goose Egg Formation name should be retained but that it should have its lower limit at the top of the Minnekahta. The Goose Egg contains sandy dolomites in the east- central Wyoming area, but because it grades laterally 43 into a gypsum anhydrite sequence near the Black Hills, it makes it difficult to determine the upper boundary in surface exposures. Petroleum Possibilities in the Minnelusa The Minnelusa Formation in South Dakota offers a number of pOssibilities for finding petroleum. Because the state of South Dakota lies in the Mid—Continent region,. structural patterns that are developed in the Rocky Mountains are much more subdued in the state. During the Laramide Orogeny, the compressive force diminished to the east and thus produced very little in the way of folding, east of the Black Hills. Some anticlines do exist in the Lemmon Syncline, but their closure is so small that economic accumulations are not present. This does not preclude larger anticlines being present. Some fault traps could be productive along the western portion of the Lemmon Syncline. One fault is known to exist there and others probably exist between the Cedar Creek Anticline and the above mentioned fault. Stratigraphic traps offer the most promising traps in South Dakota. The Minnelusa contains a number of sandstone beds, among them, the Leo sands of the Middle Minnelusa capable of producing petroleum. The impervious Opeche shale overlying the Minnelusa acts as a good seal where it is present. Along the zero line of the Minnelusa near the middle of the state, the formation thins on the underlying granite and quartzite. Where the AA formation feathers out and where overlying shales, either within the Minnelusa or the overlying Jurassic, could be found, wedge out traps are possible. Most of the explor- ation to date has been around the Black Hills. Near the zero line of the Minnelusa, very little drilling has been done. Another possibility for petroleum accumulation would be unconformities. The Opeche lies unconformably on the Minnelusa so traps such as buried topography, or a regional truncation along with buried topography present good possibilities. Again, the area near the middle of the state, where the Minnelusa thins would be worth test- ing. Other traps one could look for here would be local updip porosity pinchouts, facies changes from sandstone to dolomite or anhydrite and local porosity developments in dolomite units. CONCLUSIONS The Minnelusa Formation in South Dakota has been shown to be a predominately marine sediment that has the possibility of producing petroleum. The Minnelusa For- mation in South Dakota has been shown to be a predominately marine sediment. During early Pennsylvanian time, South Dakota was inundated by seas transgressing from the west and southwest. During middle and late Pennsylvanian time the seas regressed in a sporadic manner creating shallow water deposits and some eolian sediments. Post-Wolfcampian erosion and a climatic change to more arid conditions accompanied Opeche and Minnekahta deposition which are tongues of the Phosphoria sea. With a number of places showing favorable conditions for oil accumulation, especi- ally near the edge of the Minnelusa, the writer believes that it will only take a matter of time to test these areas and find commercial oil. Surface work has helped in determining the gross lithology of the Minnelusa in the Black Hills region, but it is now the responsibility of the subsurface geologist to determine the specific aspects of the Minnelusa in the A5 A6 rest of the state for petroleum production. Prolific production from the Minnelusa of the Powder River Basin has encouraged the industry to explore the possibilities of the Minnelusa Formation in South Dakota containing the elusive "Leo sands" which the writer believes to exhibit good possibilities for petroleum. Since seismic exploration techniques can be of little use in most areas of South Dakota because of the fact that the Opeche is underlain by porous sandstone and the matrix velocities of the two units are nearly identi- cal, intense and detailed subsurface geology will eventually be the best method for exploiting petroleum possibilities in South Dakota. REFERENCES LIST OF REFERENCES Agatston, R. S. 195A. "Pennsylvanian and Lower Permian of northern and eastern Wyoming." Amer. Assoc. Petrol. Geol. Bull., Vol. 38, pp. 508-583. Agnew, Allen F. 1958. "Oil and Gas Developments in South Dakota, 1957." South Dakota Geological Survey, Oil and Gas Investigations, Map l. . 1959. "Oil and Gas Development in South Dakota, 1958." South Dakota Geological Survey, Oil and Gas Investigations, Map 3. Allen, Albert E., Jr. 1966. "Environments of Deposition in the Minnelusa and Their Interpretation from Gamma- Sonic Logs." Wyoming Geological Association, Geo- logic Principles Permo-Pennsylvanian Symposium, 20th Annual Conference at Casper College, pp. 91-9A. Andrichuk, J. M. 1955. "Mississippian Madison Group Stratrigraphy and Sedimentation in Wyoming and Southern Montana." Amer. Assoc. Petrol. Geol. Bull., Vol. 39, No. 11, pp. 2170-2210. Baker, 0. L. 1951. "Development of Dakota Basin in South Dakota." Bulletin in the Geological Society of America, Vol. 62, No. 12, Part 2, p. 1531. Ballard, Norval. 19A2. "Regional Geology of Dakota Basin." Amer. Assoc. Petrol. Geol. Bull., Vol. 26, No. 10, pp. 1557—158A. Barnes, T. R. 1952. "The Williston Basin-~A New Province for Oil Exploration." Billings Geological Society 3rd Annual Field Conference Guidebook, pp. 97-117. Bates, R. L. 1955. "Permo-Pennsylvanian Formations Between Laramie Mountains, Wyoming and Black Hills, South Dakota." Amer. Assoc. Petrol. Geol. Bull., No. 10, pp. 1979-2002. A8 A9 f : “ m r Brady, F. H. 1931. "Minnelusa Formation of Beulah District, Northwestern Black Hills, Wyoming." Amer. Assoc. Petrol. Geol. Bull., Vol. 15, No. 2, pp. 183-188. 1958. "Evaporite Deposits in the Minnelusa Formation in the Sundance-Beulah Area, Crook County, Wyoming." Wyoming Geological Association 13th Annual Field Conference Guidebook, pp. A5—A7. Brost, D. A. and J. B. Epstien. 1958. "Fanny Peak Quad- rangle, Wyoming, South Dakota.". United States Geo~ logical Survey, Report TEI 7A0, pp. 8A-91. Burk, C. A. and H. D. Thomas. 1956. "The Goose Egg Formation (Permo-Triassic) of Eastern Wyoming." Wyoming Geological Survey, Report of Investigations No. 6. Butler, R. L. and Others. 1955. "Lithologic Correlation of Middle and Lower Paleozoic Rocks in North Dakota." 'North Dakota Geological Society,South Dakota Black .Hills, 3rd Field Conference Guidebook, pp. 38-A2. Collier, A. J., and S. H. Cathcart. 1922. "Possibility of Finding Oil in Laccolithic Domes South of the Little Rocky Mountains, Montana." United States Geological Survey Bull., 736F, pp. 171-178. Condra, G. E. and E. C. Reed. 1935. "The Permo-Pennsyl— vanian Section of the Hartville Area of Wyoming." Nebraska Geological Survey, Paper No. 9. . 19A0. "Correlation of the Carboniferous and Permian Horizons in the Black Hills and Hartville Uplift." Kansas Geological Society, lAth Annual Field Conference Guidebook, pp. 127-128. Condra, G. E. and O. J. Scherey. 19AO. "Correlation of the Formations of the Laramie Range, Hartville Up- lift, Black Hills and Western Nebraska." Nebraska Geological Survey Bulletin No. 13. Darton, N. H. 1901. "Preliminary Description of the Geology and Water Resources of the Southern Half of the Black Hills and Adjoining Regions in South Dakota and Wyoming." Twenty-first Annual Report, United States Geological Survey, Part IV, pp. A89-589. Darton, N. H. and Sidney Paige. 1925. "Central Black Hills Folio." United States Geological Survey, Atlas Folio No. 219. 50 Dille, G. S. 1930. "Minnelusa of Black Hills of South Dakota." Amer. Assoc. Petrol. Geol. Bull., Vol. 1“, NO. 5, pp. 619-6230 Eardley, A. J. 1951. Structural Geology of North America. Harper and Bros., New York. Erickson, H. 0. 195A. "Artesian Conditions in East Central South Dakota." South Dakota Survey Report of Investigations No. 7A, IV, 116 p. Fisher, J. H. 1963. "Tensleep Sandstone of the Eastern Big Horn Mountains, Wyoming." Wyoming Geologic Association, Billings Geological Society Guidebook, pp. 5A-60. Foster, Donald I. 1958. "Summary of the Stratigraphy of the Minnelusa Formation, Powder River Basin, Wyoming." Wyoming Geological Association 13th Annual Field Conference Guidebook, pp. 39-AA. Gries, John Paul. 1952. "Paleozoic Stratigraphy of Western South Dakota." Billings Geological Society, 3rd Annual Field Conference Guidebook, pp. 70-72. . 1963. "Geology of the Southern Black Hills." Rocky Mountain Association of Geologists, lAth Annual Field Conference Guidebook, pp. 189-195. . 196A. "Barker Dome Oil Field, Custer County, ISouth Dakota." The Mountain Geologist, Vol. 1, No. 1, pp. A3-A6. Gries, J. P. and J. C. Mickelson. 196A. "Mississippian Carbonate Rocks of Western South Dakota.and Adjoin- ing Areas." Billings Geological Society--North Dakota Geological Society—-Saskatchewan Geological Society, 3rd International Williston Basin Symposium Guidebook, pp. 109-118. Hadley, H. D., P. J. Lewis and R. B. Larsen, 1952. "Catalog of Formation Names for Williston Basin and Adjacent Areas." Billings Geological Society, 3rd Annual Field Conference Guidebook, pp. 132-1A3. Jaggar, T. A. 1901. "The Laccoliths of the Black Hills." U. S. Geol. Survey 21st Annual Report, Part III, pp. 171-290. Laudon, L. R. and J. L. Severson. 1953. "New Crinoid Fauna, Mississippian, Lodgepole Formation, Montana." Jour. Paleon., Vol. 27, pp. 505-36. 51 Love, J. 0., L. G. Henbest, and N. M. Denson, 1953. "Stratigraphy and Paleontology of Paleozoic Rocks, Hartville Area, Eastern Wyoming." United States Geological Survey, Chart OC AA, 011 and Gas In- vestigation. Ludlow, William. 1875. "Report of a Reconnaissance of the Black Hills of Dakota." Government Printing Office, Washington, pp. 38-65. Macauley, G. 196A. "Regional Framework of Paleozoic Sedimentation in Western Canada and Northwestern United States." Billings Geological Society-- North Dakota Geological Society--Saskatchewan Geological Society, 3rd International Williston Basin Symposium Guidebook, pp. 7-36. MacLachlan, J. and Alan Bieber. 1963. "Permian and Pennsylvanian Geology of the Hartville Uplift-- Alliance Basin--Chadron Arch Area." Rocky Mountain Association of Geologists, lAth Annual Field Con- ference Guidebook, pp. 8A-9A. Maughan, Edwin K. 1966. "Pennsylvanian and Permian Paleogeography,Tectonics and Stratigraphy in Montana and the Dakotas." Wyoming Geological Association, Geologic Principles Permo—Pennsylvanian Symposium, 20th Annual Conference at Casper College, pp. 95-108. Momper, James A. 1963. "Nomenclature, Lithofacies and Genesis of Permo-Pennsylvanian Rocks-—Northern Denver Basin." Rocky Mountain Association of Geo- logists, lAth Annual Field Conference Guidebook, pp. “1’670‘ Noble, James A. 1952. "Structural Features of the Black Hills and Adjacent Areas Developed Since Pre-Cambrian Time." Billings Geological Society, 3rd Annual Field Conference Guidebook, pp. 31-37. Peale, A. C. 1893. "The Paleozoic Section in the Vicinity of Three Forks, Montana." United States Geologic Survey Bulletin No. 110, pp. 9-56. Pye, W. D. 1953. "Structural Deformation in the Williston Basin." Amer. Assoc. Petrol. Geol. Bull. Vol. 6A, pp. 1552 (Abstract). Reed, E. C. 1955. "Correlations of the Permo—Pennsylvanian Rocks of the Black Hills with the Northern Mid- Continent Region." North Dakota Geological Society Guidebook, pp. AA-A7. 52 Roth, R. 1930. "Regional Extent of Marmaton and Cherokee Midcontinent Formations." Amer. Assoc. Petrol. Geol. Bull., Vol. 1A, pp. 12A9-1278. Rothrock, E. P. 19A3. "A Geology of South Dakota--Part I, The Surface." South Dakota Geologic Survey, Bull. No. 13. Schoon, Robert A. 1965. "Selected Formation Tops in Oil and Gas Tests in South Dakota Drilled Before January 1, 1965." South Dakota Geological Survey, Circular No. 35. Seager, O. A. 19A2. "Test on Cedar Creek Anticline, Southeastern Montana." Amer. Assoc. Petrol. Geol. Bull., Vol. 26, pp. 861—86A. 81088, L. L. 1952. "Introduction to the Mississippian of the Williston Basin." Billings Geological Society, 3rd Annual Field Conference Guidebook, pp 0 65-69 0 Stone, W. J. 1966. "Interpretation of Pennsylvanian- Permian Contact in the Eastern Powder River Basin Region, Wyoming." The Compass, Vol. AA, No. 1, pp. 5-9. Stratton, E. F. and R. D. Ford. 19A9. "Electric Logging." Subsurface Geological Methods, Department of Publi- cations, Colorado School of Mines. Tenny, C. S. 1966. "Pennsylvanian and Lower Permian Deposition in Wyoming and Adjacent Areas." Amer. Assoc. Petrol. Geol. Bull., Vol. 50, No. 2, pp. 227-250. Todd, J. E. 189A. "A Preliminary Report on the Geology of South Dakota." South Dakota Geological Survey Bulletin No. l. Trotter, J. R. 1963. "The Minnelusa Play of the Northern Powder River, Wyoming and Adjacent Areas." Wyoming Geologic Association--Billings Geological Society .Guidebook, pp. 117-122. Tranter, C. E. and C. K. Petter. 1963. "Lower Permian and Pennsylvanian Stratigraphy of the Northern Rocky Mountains." Wyoming Geologic Association-- Billings Geological Society Guidebook, pp. A5-53. Verville, G. J. 1957. "Wolfcampian Fusulinids from the Tensleep Sandstone in the Big Horn Mountains, Wyoming." Journal of Paleontology, Vol. 31, No. 2, pp ' 3’49-352 o 53 Webster, Michael S. 1963. "Regional Study of the New- castle Formation of South Dakota." Unpublished Master's Thesis, Michigan State University. Weller, J. Marvin. 1960. Stratigraphic Principles and Practice, Harper and Row, Inc., New York. Wilson, Roy A. 1922. "The Possibilities of Oil in South Dakota-~A Preliminary Discussion." South Dakota Geologic Survey, Bull. No. 10. Winchell, N. H. in Ludlow, W. 1875. "Report of a Reconnaissance of the Black Hills of South Dakota." U. S. Govt. Printing Office, Washington, p. 65. APPENDIX TYPE SECTION OF THE MINNELUSA FORMATION TYPE SECTION OF THE MINNELUSA FORMATION SW, 1/A, Sec. 10, T. 52 N., R. 61 W., exposed in Sundance Canyon, Crook Co., Wyo. (After Brady, 1958) Thickness (Feet) Opeche Red Shale Opeche Gypsum Unconformable contact with Opeche Formation 21. Buff, dense, arenaceous limestone; fossiliferous; regional member 20. Light brown, fine grained, well rounded, friable, gypsiferous sandstone; regional member 19. Soft, white, friable gypsum 18. Thinly bedded, pink to purple striped limestone; fossiliferous 17. White, massive gypsum 16. Soft, red, gypsiferous shale 15. White, massive gypsum 1A. Yellow to buff, massive, medium grained sandstone, regional member 13. White, massive, dense anhydrite 12 10 10 22 2 10 A 30 30 8 12. Interbedded gray limestones, red shales, and buff siltstones; purple siltstone and gypsiferous conglomerate near the top; fossiliferous; regional member 11 55 56 Thickness (Feet) ll. Red, brown, and pink, fine-grained, evenly bedded sandstone; regional member 3O 10. Gray, dense, arenaceous limestone; inter- bedded with brown, gray, and purple shales and siltstones; fossiliferous; regional member White, massive, dense gypsum and anhydrite 15 Gray, dense limestone; fossiliferous White, dense, massive gypsum and anhydrite Interbedded gray limestone and purple shale Soft, white, friable gypsum Gray, very dense, dolomite, lithographic, well-bedded limestone; fossiliferous White anhydrite Yellow to buff, calcareous, ferruginous, medium to coarse grained sandstone; regional member Dense, yellowish to lavender, crystalline limestone; brown spots; regional member; not fully exposed Creek bed 10 ) A L 257 MICHIGAN STATE UNIV. LIBRARIES IWWIIIIIIHIIIIWWIWWIIWWII“ 31293104748508