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Home , 100th meridian west, Niobrara Formation, Niobrara River, Valentine Formation

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Earth and Atmospheric Sciences, Department Papers in the Earth and Atmospheric Sciences of

5-1994

Geologic Framework of the Drainage Basin and Adjacent Areas in Generally East of the 100th West and West of the

Robert F. Diffendal University of Nebraska-Lincoln, [email protected]

Michael R. Voorhies University of Nebraska-Lincoln, [email protected]

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Diffendal, Robert F. and Voorhies, Michael R., "Geologic Framework of the Niobrara River Drainage Basin and Adjacent Areas in South Dakota Generally East of the 100th Meridian West Longitude and West of the Missouri River" (1994). Papers in the Earth and Atmospheric Sciences. 94. https://digitalcommons.unl.edu/geosciencefacpub/94

This Article is brought to you for free and open access by the Earth and Atmospheric Sciences, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Papers in the Earth and Atmospheric Sciences by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Geologic Framework of the Niobrara River Drainage Basin and Adjacent Areas in South Dakota Generally East of the 100th Meridian West Longitude and West of the Missouri River

R.F. Diffendal, Jr. and M.R. Voorhies

Nebraska Geological Survey Rep。同 。f Investigations No.9

Conservation and Survey Division Institute of Agriculture and Natural Resources University of Nebraska-Lincoln University of Nebraska Board of Regents Robert M. Allen, Hastings Don S. Blank. D.D.S.. McCook Nancy Hoch, Nebraska City Nancy L. O'Brien , Ph.D ., Waterloo John W. Payne, Kearney Margaret Robinson , Norfolk Rosemary Skrupa, J.D ., Omaha Charles S. Wilson , M.D., Lincoln

Administration L. Dennis Smith. Ph.D.. President Graham B. Spanier, Ph.D., Vice President and Chancellor, University of Nebraska-Lincoln Irvin T. Omtvedt, Ph.D., Vice Chancellor forAgriculture and Natural Resources Perry B. Wigley, Ph.D ., Director, Conservation and Survey Division

The Conservation and Survey Division of the University of Nebraska is the agency designated by statute to investigate and interpret the geologically related natural resources of the state, to make available to the public the results of these investigations, and to assist in the development and conservation of these re­ sources.

The division is authorized to enter into agreements with federal agencies to engage in cooperative surveys and investigations in the state. Publications of the division and the cooperating agencies are available from the Conservation and Survey Division , University of Nebraska , Lincoln, Nebraska 68588-0517.

It is the policy of the Conservation and Survey Division, as it is of the Univer­ sity of Nebraska-Lincoln , not to discriminate on the basis of and to provide infor­ mation and educational programs to all regardless of sex, age, handicap , race, color, religion, marital status, veteran's status, national or ethnic origin or sexual orientation.

Publication and price lists are furnished upon request.

May 1994

II Contents Abstract .. Introduction ...... ………………………………...... 1 Pre- Geology...... ……………………………… …...... 2 Erathem-Cretaceous System-Lower Cretaceous Series...... 5 Mesozoic Erathem-Cretaceous System-Upper Cretaceous Series...... 5 Cenozoic Erathem-Tertiary System-Upper to Lower 5 Cenozoic Erathem-Tertiary System-Upper Oligocene to Lower 7 Cenozoic Erathem-Tertiary System-Miocene Series...... 7 Cenozoic Erathem-Tertiary System- Series...... 8 Cenozoic Erathem- System- and Holocene Series...... 8 Possible Evidence of Structures...... ……………………………………… …...... 8 Geologic Hazards in the Area...... 8 References Cited ...... ………………………………… 9 Ill ustration 1. Preliminary Geologic Map of Eastern Niobrara River Drainage Basin and Adjacent Parts of South Dakota 4

Tables 1. Cenozoic and Late Mesozoic Deposits Along the Eastern Part of the Niobrara Drainage Basin in Nebraska and in Adjacent Parts of South Dakota West of the Missouri River ...... ……………………………...... 3 2. Cenozoic and Late Mesozoic Geologic Time Spans, Formations , Sediment Types, Typical Fossils, and General Environments­ Eastern Niobrara Basin and Adjacent Parts of South Dakota West of the Missouri River...... … …...... 6

III Geologic Framework of the Niobrara River Drainage Basin and Adjacent Areas in South Dakota Generally East of the 100th Meridian West Longitude and West of the Missouri River

by R. F. Diffendal, Jr.' and M.R. Voorhies2

Abstr百ct includes the present scene and the geologic General geology and stratigraphy of the history of the basin. Readers who are inter­ Niobrara River drainage basin in Nebraska and ested in the geology of the western pa 时of the adjacent parts of South Dakota generally west basin (not included in this repo 时 ) should read of the Missouri River is reviewed. Of particular the works of Swinehart and Diffendal (1990) , importance are the correlation of the Long Pine Swinehart and others (1985) , and Souders Formation of Pliocene age in Nebraska with (1981) cited in the references , the works of R. the Herrick Gravels in South Dakota, the rec­ M. Hunt, Jr., of the University of Nebraska State ognition of the members of the Ogallala Group Museum and his students (Hunt, 1978, 1990; named by Skinnner, Skinner and Gooris (1968) Hunt and others, 1983; Yatkola, 1978), and the and by Skinner and Johnson (1984) in the work of Skinner, Skinner, and Gooris (1977) in basin, the acceptance of the relationships of the library of the University of Nebraska-Lin­ the Miocene and older Tertiary units in the ba­ coin. These repo 时s contain references to most sin to those in the part of the study area in of the earlier geologic work done in that area. South Dakota as proposed by Skinner andTay­ The geology of the area has been studied lor (1967), Skinner, Skinner and Gooris (1968) for a long time. As early as 1845, Charles Lyell, and by Skinner and Johnson (1984), and the the famous English geologist, published a geo­ recognition of the Rosebud Formation of the logic map of the that showed Arikaree Group (Skinner, Skinner, and Gooris, the presence of Cretaceous strata in the area 1968) in the basin. Rocks now included in the about the mouth of the Niobrara River and the Rosebud were placed previously in the White adjacent (Diffendal , River Group by the Conservation and Survey 1993). The Warren, Meek, and Hayden sur­ Division (Burchett , 1986). A refined geologic veys in the late 1850s resulted in consider­ map of the area shows the currently known able expansion of knowledge of the geology distributions of all of the major units, including of the , including the Niobrara Ba­ the Long Pine/Herrick, the Rosebud, and the sin. In the late 1800s and the early 1900s, the Chadron formations. none of which has been focus of work in the basin was mainly paleon­ shown on a map of the study area previously. tological. The history of these activities is re­ viewed in detail by Voorhies (1990b , 1990c). Introduction Considerable debate arose in the 1930s about This report covers the geology of the east­ the stratigraphic names of some of the strata ern pa 时of the Niobrara Basin in Nebraska and in the basin (Johnson, 1936, 1938; Lugn, 1938, adjacent pa 时s of South Dakota. This geology 1939) and was resolved then for a time (Condra and Reed, 1959) Our present understanding of the general

'Research Geologist, Conservation and Survey Division , geology of the Niobrara drainage basin east University of Nebraska-Lincoln of the 100th meridian comes from the works

2Professor, Department of Geology and University of Nebraska of a limited number of geologists who have State Museum studied the area and written reports about it mostly since 1950. We present one figure and (1990), and Guthrie (1990). Considerable work two tables that show our view of the current has been done and continues to be done by state of geological knowledge in the area. several geologists, hydrogeologists, and other Many of the formation and member names researchers on the geology in and around the applied to Cenozoic strata in the area were site of the proposed low-level radioactivewaste defined by Morris Skinner and his co-workers storage facility in Boyd County (for example, at the American Museum of Natural History in Pierce, 1989; Rahn and Davis, 1989). Mod­ New York (table 1). M. R. Voorhies of the NU ern soil surveys have been completed for all State Museum has also published on the ge­ of the counties in the eastern part of the basin ology and paleontology of the Cenozoic in Nebraska and in the study area in South units in the basin (Voorhies, 1969, 1971 , 1973, Dakota (Indra, 1979; Manhke and others , 1974 , 1981 , 1985 , 1987a, 1987b, 1990a, 1978; Plantz and Zink , 1980; Ragon and oth­ 1990b, 1990c, and Voorhies and Goodwin , ers, 1983; Schulte, in press; Shurtliff and oth­ 1989). Other paleontological studies were ers , 1988 , 1990; Voightlander and others , done by Backlund and others (1991), Cobban 1992; and Zink and Schultz, 1985). Geologic (1951) , Cobban and Scott (1964) , Dietrich maps of the study area in South Dakota have (1951), Evander (1978), Haffner and others been prepared by Baker and others (1952), (1990), Johnson and Milburn (1984), Landon Collins and French (1958), Schoon and Sevon (1985), Loetterle (1937), and Wellstead (1981). (1958), Stevenson and Carlson (1950, 1951), Groundwater studies that included consider­ and Stevenson and others (1958, 1959). The able information on the geology of parts of the area to the east of the study area in Nebraska lower basin were done by members of the U.S. was mapped by Burchett and others (1988). Geological Survey and members of the Con­ The authors of this report currently are pre­ servation and Survey Division of the Univer­ paring a geologic map of the O'Neill 10 x 2° sity of Nebraska-Lincoln: Condra (1903) , area at a scale of 1:250,000 in cooperation Cronin and Newport (1956), Gosselin (1991), with the U.S. Geological Survey. Newport (1959), Reed (1944), Souders (1976), and Souders and Shaffer (1969). Schulte (1952) and Mendenhall (1953) did theses on Pre-Cretaceous Geology the geology of two counties and pa 时of a third in the basin. What we know about the pre-Cretaceous ge­ Damsite investigations were done by L. D. ology of the Nebraska part of the eastern Cast and other workers at the U.S. Bureau of Niobrara Basin and areas to the south adja­ Reclamation and by workers in other agen­ cent to the basin comes from logs and samples cies and organizations (Cast, 1988; Niobrara from about 50 oil and gas tests and from geo­ River Basin Development Association , 1951; physical surveys. rocks include U.S. Bureau of Reclamation , 1952 , 1962 , mostly metamorphic rocks and some granite. 1977,1978,1980,1992; U.S. Soil Conserva­ An extension of the Quartzite occurs tion Service, 1973; U.S. Power and Water beneath the easternmost part of the basin Resources Service, 1980). Geology and (Carlson, 1993). and rocks groundwater studies in the South Dakota part have been found only in the southeasternmost of the map area include those by Hedges pa 时of the area included in figure 1. Ordovi­ (1975) , Simpson (1960) , and Christensen cian and rocks occur from the (1974). J. E. Todd (1912) wrote an early work southeastern part of the mapped area in Ne­ on Pleistocene drainage development in the braska northwestward into South Dakota basin that was followed by works by R. H. (Carlson , 1993). -age rocks Williams (1984) and Voorhies and Goodwin have been found beneath the western part of (1989). Landforms have been analyzed for the basin, but no , , or Juras­ pa 时s of the area by Flint (1955), Swinehart sic rocks are known (Carlson, 1993). 2 Nebraska South Da kota

Cenozoic Erathem Cenozoic Erathem Quaternary System Quaternary System 六 H o l o c e n e and Pleistocene Fluvial Terrace Deposits 六 H o l o c e n e and Pleistocene Fluvial Terrace (Up to Five) Deposits Holocene and Pleistocene? Holocene and Pleistocene? Eolian Sand Eolian Sand Pleistocene Peoria Loess (And Possibly Older Loesses) Pleistocene Loess *Pleistocene Unnamed Fluvial Units Filling Paleovalleys 六 ( E q u a l to Bon Homme Gravel and Tyndall (Two or More) Sand of Christensen , 197 句 ， east of Missouri River) Tertiary System Tertiary System Pliocene Series Pliocene Series 六 P e tt i j o h n Formation (Skinner in Skinner and Hibbard , 1972) 六 D u ffy Formation (Skinner in Skinner and Hibbard , 1972) 。2 六六 Lo n g Pine Formation (Skinner in Skinner and Hibba rd , 1972) 去 H e r r i c k Gravels (Stevenson and Carlson , 1950) 六六 K e i m Formation (Skinner in Skinner and Hibbard , 1972) Miocene Series Miocene Series Ogallala Group (Darton , 1899; Revised by Lugn , 1938; Ogallala Group Further Revised and Expanded by Swinehart and Others , 1985) Ash Hollow Formation (Engelmann , 1876) Ash Hollow Formation *Unnamed Hemphi Ilian Member (Skinner and Johnson , 198 件 ) 六六 M e r r i tt Dam Member (Skinner and Johnson , 198 与 ) 六六 C a p r o c k Member (Skinner , Skinner , and Gooris , 1968) 六 C a p r o c k Member (Barbour and Cook , 191 7) Valentine Formation 六六 B u r g e Member (Skinner , Skinner , and Gooris , 1968) 六 B u r g e Member 六六 D e v i( ' s Gulch Member (Skinner , Skinner , and Gooris , 1968) Devifls Gulch Member 六六 C ro o k s t o n Bridge Member (Skinner , Skinner , and Gooris , 1968) 六六 C o r n e ll Dam Member (Skinner and Johnson , 198 句 ) 六六 F o r t Randall Formation (Skinner and Taylor , 1967) Lower Miocene-Upper Oligocene Series Lower Miocene-Upper Oligocene Series Arikaree Group (Darton , 1899; Revised by Lugn , 1938) 六六 T u r t l e Butte Formation (Skinner, Skinner , and Gooris , 1968) 女 R o s e b u d Formation (Matthew and Gidley , 190 句 ; Detailed Rosebud Formation by Skinner , Skinner , and Gooris , 1968) Lower Oligocene-Upper Eocene Series Lower Oligocene-Upper Eocene Series White River Group (Meek and Hayden , 1858; Refined by White River Group Lugn , 1938) ? (Darton , 1899) Chadron Formation? Mesozoic Erathem Mesozoic Erathem Cretaceous System Cretaceous System Upper Cretaceous Series Upper Cretaceous Series (Meek and Hayden , 1862) Pierre Shale (Meek and Hayden , 1862) Niobrara Formation

六六 = C o n t a i n s fossil mammal remains of national /international significance 六二 C o n t a i n s fossil mammal remains of local/regional significance

Table 1. Cenozoic and Late Mesozoic Deposits Along the Eastern Part of the Niobrara Drainage Basin in Nebraska and in Adjacent Parts of South Dakota West of the Missouri River Kp PRELIMINARY GEOLOGIC MAP 30'-1 也 T工1f 2rq j俨 OF EASTERN NIOBRARA RIVER DRAINAGE BASIN Kp dJr? 守 f AND ADJACENT PARTS OF SOUTH DAKOTA To To To By

R.F. Diffendal , Jr. and M.R. Voorhies - 1994

OEEC 5 15D 50 2D M L 卢巳cu 王王一 王

二

D 叫 门 CL γl < 1 0 1 ζ U K L ER b

飞t

43°00'

30'

PLIOCENE INDEX MAP 15' 斗 To 飞J、1 MIOCENE !SOUTH DAKOTA FORT "O "lMA~IC~ Tlr

~ '-'RT ~ B】 γ ~ E Ttb L MIOCENE U OLIGOCENE RCS!::: 8 u0 FQH~I 同 T r

WH'TE f' IVER Map from work 01 the authors and L.OLIGOCENE- maps and articles listed i 门 r e f e r e n c e s U EOCENE …~.; T 二l一Tc一 I South Dakota Works of M Skin 门er and others DaKota ~'E F' 问 ~ -Kp U CRETACEOUS Nebraska Works of M , Skinner and others 飞 K n M , R , Voorhies , Conservation and

us. Bureau of Reclamation reports 哼A ι'l 内 o 寸 2°0 I 98°00' 100°00' 45' 30' 15' 99°00' 45' 30' 15'

Fig. 1. Preliminary Geologic Map of Eastern Niobrara River Drainage Basin and Adjacent Parts of South Dakota Mesozoic Erathem-Cretaceous time. 丁his time the sea-floor System-Lower Cretaceous Series conditions were different , and the sediments that were deposited were mostly dark muds The Dakota Group of age with sulfate and other minerals. While clam and is a source of groundwater in pa 时s of the ba­ oyster fossils are common in the Niobrara sin and is known to occur beneath the map (Pabian, 1970), they are largely absent from area, as do other Cretaceous formations older the Pierre. This indicates that the sea floor was than the Niobrara. inhospitable to bottom organisms most of the time. Organisms that floated and swam in the Mesozoic Erathem-Cretaceous waters above the floor, however, are present System-Upper Cretaceous Series as fossils in the Pierre, proving that at least The oldest Cretaceous formation exposed the surface waters were habitable. Bentonites in the area is the Niobrara (fig. 1; tables 1 and also occur in the Pierre, so volcanoes must have been present in distant areas at the time 2). Limestones and chalks of the Niobrara crop the Pierre accumulated. At the end of Pierre out discontinuously along the sides of the deposition in the area , the seas withdrew. A Missouri Valley, the lowermost Niobrara Valley major gap occurs in the geologic record above and lowermost Creek valley. The the Pierre (table 2). Exactly what happened in Niobrara underlies the entire study area. The the area between deposition of the Pierre and formation was deposited on the floor of a the Chadron Formation of Cenozoic age is not shallow sea that extended from the position of known. the present south to the present Gulf of . Marine organisms abounded in the waters of this seaway, and their skeletal Cenozoic Erathem-Tertiary System­ elements form the major part of the formation. Upper Eocene to Lower Oligocene Beds of bentonite (a claystone formed from altered volcanic ash) indicate that volcanoes Weathered uppermost Pierre Shale occurs were present in land areas to the west that in places, indicating that soil-forming pro­ bordered the seaway and that eruptions from cesses were going on in the area before depo­ these volcanoes affected the seaway. Most sition of any Cenozoic rocks.The unconformity paleogeographic reconstructions show that our at the top of the Pierre has considerable relief part of the seaway was much closer to the and has a dendritic drainage pattern resem­ in Niobrara times than it is today, so bling those forming in lands underlain directly we have inferred from this and the types of by Pierre Shale today. fossils present in the deposit that the waters The oldest Cenozoic formation known in the of the seaway were warm. At the end of study area is the Chadron Formation of the deposition of the Niobrara, the seaway White River Group. So far as we know, the shallowed for a time and an erosion surface Chadron in Nebraska was first observed in the (unconformity) formed (DeGraw, 1975). The study area by V. H. Dreeszen and in South amount of time between the end of deposition Dakota by M. F. Skinner.The Chadron is known of the Niobrara and the start of deposition of to crop out in only three small areas in Keya the overlying Pierre Shale is not known for Paha County in Nebraska and in the Turtle certain , but we have used information given to Butte area in South Dakota (fig. 1). From what us by D. K. Watkins (1993 , personal we can tell from these limited exposures and communication) to estimate the gap at about from other repo 时s ， the Chadron filled valleys 6 million years (table 2). eroded into the Pierre. Clays in the Chadron Whatever the length of time represented by are derived from alteration of volcanic ash and the Pierre/Niobrara unconformity, the seas from minerals such as feldspars in the sedi­ deepened over the study area once again in ments. Western volcanism contributed consid- 5 骨 M IP FORMATION SEDIMENT TYPES KEY GENERA OR SPECIES TYPICAL FOSSILS ENVIRONMENT

Sand and grave1scaanpdsystrath terraces1sa 门d ， ve 叩 习习乡好予万-z:;;ry: pale brown; silt , sandy , ve 叩 p a l e brown 坠主且卫 Large grazing mammals and rodents Glacial a 门d 门terglacial climates Sand and gravel from distant and local Mamm川hus alternate 芳芳皆~sources fill paleovalleys

Sand and gravel , Sand. silt. and clay. red Pettijohn-Keirn Fms 门r aO roar门n tlon ClbUrdowesnysat trlftlheOdSl tseandf d 9RrOaCveKl Fo s s l l S Co m m On G 「a z l nSgh h Or s e S 91an t Ca m e ls Sh o rT j a We d Mountai 们s. cross-stratified Sa 门 d an dY Steqomastodon Borophao.us elf 们gdogS a re p red Om lnant largt e r m am malS Gloantocamelus. 0 门 d a t r a Trlevemrplneerawteoogdra1asnSdlas 门 d / p a r k l a n d with locally derived gravel filii 门9 channels enUvrvl orownlmngen「To dwehnltlSe (gmCUpShke「 rasT S 9fVO0U1neds saqnLJdlr reS lhs「)ewshsow111da1dcaap1et a aO 门tetmo pseteraptpee 门 u |la门y E且 吐u s_.lIJ9Jich_9_hlPRμsLj3_~9巴 'j5 gsaranddeas dptwh ae rndtotogCr alay yS-1a1 nlMd dy Cp k to gray climate marsr, e 门vlronment

bill斗旦国卫 'j]， 已旦旦旦旦旦

Fossils abundan t. especially tortoises , grass seeds. aηd large grazing 门 e (ho~ses ， sFaovrea sntnsa SpeOrCsClsLIiPoY nll门ytelnrf1rLIlVveesr vaH eysy Sw altnhdlsetsoS co ngSraOylldCaa1leCda rSeaonLIdSa1nndte vrboelCdadneldc Pseudhippario f1 B. morrisi mammals rhinos , camels. ruminants) Ash Hollow Formatio门 Ustatochoerus skinner Ogallala Group ash lentils; overlain by thi 门ner bedded malO.C an们αy veb 门ro Oc门 Climate stili warm but drier than 们de dEeropwOSselt SrsMa sapqeUcaletlSc of ewkseatresSb eccoommme Oenxt i n fClall |eCda rwe1o1hUsusf1acon nd SstOOll a1teydousnagnedr d e ep Cuts before Pseudhipoarion Barbourofells U 旦且出卫 旦且旦旦Ldi 'iJ主皿卫豆卫 阵乙。=z::::2::22。 U 川山皿/~川 d Fossils abunda门 t Aquatic species include fish. alligators , turtles Fossil Sand pale ouve fnable cross stratMled1| 「etrUSLJm M fu 「ca ↑us 旦旦旦旦05 门 门s JdS Sh re vvs Valentine Formation sandstone hpale ollve a 「QlllaceOMone 旦旦旦CFasLι」丘且l LL旦旦i volcanic ash. light gray: sand and gravel , I s且旦旦旦卫 lL wLaartgee!epderm anen t stream S a 门dwell Ogallala Group medius cross-s•ratified fo r e srtS SfalOvOad门 11ap l a l nWS OOdSlUaP门PdOsr t l no ng Bouromervx La rge r m am m alsmClud e abu nd ant Ppl ro bosc!dea n S (b otn lOcnogthl awed 旦旦旦旦旦且巳且主 ?F--o-rt 叩Ra n dal l F一o rrn-a--u on-f> gomphotheres and true mastodons). tapirs. rhinos. horses. challcotheres , interfluves. Frost-free climate Cl ay sandy Clayb and s llty Sand ligrl hT red 川n ph eo cocfeadrlemSamomreaolsd Ogn 「1as z ecmamlnedlslVldruuam!lylnaOnUttsn umanbder CbarrOnWl vSoerress at Ammoosnig SlttheeS grnady PInk pale ollve ba lteod|U U and calcareous concretion horizo门S but browsers are more diverse (larger number of taxa) present: strata massive 扎，1 e r v c o d u s necatus shrammi

Enhvdrocvon crassidens SSllllttssttoonneeywCahllci ea 『 teoo ullsghtC lgarya y!wthulftfeaceSoaunsd Turtle Butte Formation ArchaeohlPPus equlnanus Fossils u 门common Small but diverse samples of fish , lizard , turtle , and Channel a 门d floodplai门warm Arlkaree Group and sil l. reddish brown; strata massive to MAr呈c♀h且a应e o豆t且h ♀[L h.♀且主卫且」 mammal fossils known climate thick bedded erlum trippensls ~?:Z:旦￥= 7 Siltstone and silty sandsto门e pln.klsh i gray to brown , minor olive colors massive to stratified; tuffaceous 旦D旦e旦s m旦且旦1旦且旦旦旦旦旦工e旦J豆U♀主 l 门eludes local eha 门 门els filled with M Floodplai们l 门seaso们a Rosebud Formation FOSSilS rare , A few oreodont , rodent and iηsectivore jaws Ily a rid Arikaree Group reworked siltstone and sandy siltstone envlronmen竹 gbravels w lth Sllts fil l 门lnkg npdO 「e sp ac es 」E旦型旦坠且旦丛旦E且呈句I巳QEr L旦 etween grains. pale pink and some light olive colors , massive to grossly cross stratified m

~and ， while; sandy clay. tan to olive Formatio门 ? > Chadron , Cwlhalyt e Sanadnyd Clatayn andt ufSfaanCdeOUpSu rp!ed e erepdly No identifiable fossils known White River Group Warm. humid fluvial weathered

级级 千L

Nannofossils Slahmallnea1tebdlackcyh aglkrayyS haanl ed ybrollwghnt[ghrianyly Foraminifera Pierre Shale Bivalves Shallow marine laminated; bentonite , white to gray Am m onOld C epFhalopOdS SMhaarlrnkes RBeopn们 F i s h

>

Nannofossils Foraminifera Ch alkySh ale y1S m ed1um grav l lm e ston e Ostracods Formatio门 Bivalves Niobrara gberanyton yuee ll owwhlteh-oSrtarantglfeled graylsh Or an ge 3 Ammonoid Cephalopods Shallow marine BMoanrlyneFlRShepshhleaSrks

件 M YB P ~ Millions of Years Before Present

EZ2LJ~ No R 川s of This Age Known in Area

Table 2. Cenozoic and Late Mesozoic Geologic Time Spans , Formations, Sediment Types, Typi­ cal Fossils, and General Environments--Eastern Niobrara Basin and Adjacent Parts of South Dakota West of the Missouri River erable sediment in the form of airfall ash to fossils and its large volume of volcaniclastic the Chadron (Swineha 时and others, 1985). sediments.

Cenozoic Erathem-Tertiary System­ Cenozoic Erathem-Tertiary System­ Upper Oligocene to Lower Miocene Miocene Series There is another unconformity separating A long period of erosion separates the Turtle the Chadron from the overlying Rosebud For­ Butte Formation and older units from the mation (table 2). The Rosebud was deposited younger Miocene units assigned to the in paleovalleys eroded into both the Chadron Ogallala Group. Skinner and Taylor (1967) and the Pierre. The Rosebud rock types are described the Fort Randall Formation , which noted in table 2. The sand and silt in the Rose­ lies unconformably above the Pierre Shale in bud is dominantly composed of volcanic de­ South Dakota at the Bijou Hills east of the Mis­ bris. Gravels in channel fills within the Rose­ souri River, and in the remnants west of the bud are mostly reworked older pieces of Rose­ river called the lona Hills, etc. (fig. 1; tables 1 bud. This is also true of gravels at the base of and 2). While the rocks somewhat resemble the formation , but these may also include the older Turtle Butte Formation , they contain pieces of Chadron and Pierre rocks as well. A much younger fossils. Skinner and Taylor borrow pit on the east side of U.S. Highway thought that the formation was equivalent in 183 south of Springview about 2 mi (3 km) age to the Lower Snake Creek beds of west­ north of the Niobrara River has multiple cuts ern Nebraska, but proboscidean and other fos­ in the Rosebud Formation filled with crudely sils found subsequent to their report indicate stratified siltstone gravels that may have been a somewhat younger age for the formation. We deposited by debris flows. An erosion surface have shown this in table 2. So far as we know, separating two pa 时s of the Rosebud is visible the Fort Randall Formation is restricted to the to the east of the south abutment of Norden area in South Dakota shown on figure 1. Bridge along the Niobrara just west of the study A brief hiatus separates the Fort Randall area. These last two localities demonstrate that from the main parts of the Ogallala Group in multiple cutting and filling of paleovalleys took South Dakota, but in Nebraska the lowermost place during formation of the Rosebud in and parts of the Valentine Formation are contem­ adjacent to pa 叫s of study area. poraneous with it. Skinner and co-workers The Rosebud Formation crops out exten­ (table 1) have subdivided the Ogallala's two sively along valley sides in the western pa 时of formations , the Valentine and overlying Ash the study area (fig. 1) and also has been found Hollow, into a number of members. These in isolated small areas in the Verdigre Creek members do have lithologic differences that drainage basin (fig. 1; and in Schulte, 1952, allow them to be traced laterally in outcrops. and Voorhies, 1973). Burchett (1986) called No one has successfully traced them in the these exposures pa时of the White River Group, subsurface, however. They also have not been but we believe that they are younger and are widely recognized in South Dakota , but Skin­ the basal pa 时of the Arikaree Group instead, ner, Skinner, and Gooris (1968) reported some following the opinions of M. F. Skinner on this of them at Turtle Butte. Within the Valentine point. Formation , only the Devil's Gulch Member In South Dakota, a younger unit called the seems to be conformable everywhere. All the Turtle Butte Formation (fig. 1; tables 1 and 2) other members are complex valley fills that unconformably overlies the Rosebud (Skinner, often look conformable locally, or even region­ Skinner, and Gooris, 1968). So far as we know, ally, but are shown in Skinner and Johnson this unit occurs only atTurtle Butte. It has been (1984) to be far more complex. The basal included in the Arikaree Group with the Rose­ member of theAsh Hollow Formation , the Cap bud because of the stage of evolution of its Rock, is also a regional calcium-carbonate-ce- 7 mented marker bed, but fills paleovalleys in from the or other areas. Pebble stud­ some places. The other two members of the ies by Diffendal and colleagues now underway Ash Hollow also fill paleovalleys eroded into may answer this question. Locallyoverlying older beds (Skinner and Johnson , 1984). Mul­ the Long Pine are the Duffy and Pettijohn for­ tiple cutting and filling of paleovalleys during mations. They are known to occur only in the deposition of the Ogallala Group has been rec­ vicinity of Long Pine and the upper Elkhorn ognized in western Nebraska (Swinehart and River valley in Nebraska. All four units have Diffendal, 1990), and this seems to be the case been lumped together on figure 1 for reasons in places in north-central Nebraska as well , of scale. albeit usually on a much more subdued scale. The Ogallala Group in the study area has Cenozoic Erathem-Quaternary yielded truly remarkable accumulations of fossil System-Pleistocene and Holocene vertebrates. Many of these species are noted Series in the papers of Skinner and his colleagues. The State Historical Park The Quaternary geologic history of the study in northwestern Antelope County is one of the area is complex. Several geologic units are most spectacular of these sites found to date present , and many of these are unconform­ and has been described in detail by Voorhies able. Noteworthy are the valley fills along (1985, 1990a). Ponca Creek. the eolian sands of the Nebraska Sand Hills, several strath terraces in various Cenozoic Erathem-Tertiary System­ drainages, and Holocene alluvium. These are Pliocene Series noted on tables 1 and 2, but except for the main part of the Sand Hills, are not shown on Skinner and Hibbard (1972) recognized four figure 1. We are investigating these as pa 时of formations (table 1) now placed in the Pliocene. our mapping project and plan to show at least The oldest of these , the Keim Formation , fills some of them on the 1:250,000 geologic map. a narrow paleovalley north of Ainsworth , Ne­ braska. The much more widespread Long Pine Possible Evidence of Structures Formation and its equivalent in South Dakota , We have not observed faulting in the area , the Herrick Gravels, crop out widely in the study area and occur in the subsurface. Skinner and but several features may indicate structural Hibbard (1972) thought that the Long Pine was effects. The discontinuous exposures of the an outwash deposit from the Nebraskan Gla­ Rosebud and Chadron along the Niobrara River near the western margin of the study area ciation , but works by Stanley (1971) , Stanley and Wayne (1972) , Swinehart and others may indicate structural control. The distribu­ tion of the Paleozoic rocks shown by Carlson (1985) , and Swinehart and Diffendal (1990) have demonstrated conclusively that the flu­ (1993) may also be structurally controlled. The vial system that deposited the Long Pine came northeastward trend of the northernmost out­ from the Southern in south­ crop belts of the Fort Randall , Ogallala, and ern and north-central . Long Pine/Herrick units on figure 1 may also The Long Pine is a braidplain deposit that indicate structural control , as may lineaments fills a very wide paleovalley. This deposit con­ on Landsat images. Displacements along frac­ tinues across the state line into South Dakota tures in the Pierre east of Spenser Dam may where it has been mapped as the Herrick Grav­ indicate faulting or landslides. els. Fossils from the South Dakota deposits are from the Blancan Land Mammal Age Geologic Hazards in the Area (Pinsof , 1985), as are those from Nebraska. Landslides have been and continue to be Some of the northwesternmost parts of the observed in the Nebraska pa 时of the study area Herrick may have been deposited by rivers by D.A. Eversoll and other workers at the Con- 8 servation and Survey Division of the Univer­ Cobban , W.A., 1951, Scaphitoid cephalopods sity of Nebraska-Lincoln. They occur com­ of the : U.S. Geological monly in parts of the Pierre Shale, but also Survey Professional Paper 239, 42 p. occur in other units. We have seen them de­ Cobban , W.A. , and Scott, G.R. , 1964, velop in the Pierre and the Fort Randall in Multinodose scaphitid cephalopods from the South Dakota as well. Flooding is also a prob­ lower part of the Pierre Shale and equiva­ lem in some areas. Earthquakes have occurred lent rocks in the conterminous United States: in the study area (U.S. Water and Power Re­ U.S. Geological Survey Professional Paper sources Service , 1980). 483-E , 13 p. Collins , S.G., and French , T. J., 1958, Geology References Cited of the Wewela quadrangle: South Dakota Geological Survey, scale 1:62,500. Backlund , D., Gabel, M.L., and Tieszen , L.L. , Condra , G.E., 1903, Geology and water re­ 1991, An environmental gradient in the Ter­ sources of a portion of the Missouri River tiary Great Plains as indicated by stable car­ Valley in north-eastern Nebraska: U.S. Geo­ bon isotopes from organic carbon in plant logical Survey Water-Supply Paper 215 , fossils: South Dakota Academy of Sciences 59 p. Proceedings, v. 70, p. 99-108. Condra , G.E., and Reed, E.C., 1959,The geo­ Baker, C.L. , Stevenson, R.E., and Carlson , logical section of Nebraska: University of L.A., 1952, Areal geology of the Herrick Nebraska, Conservation and Survey Division quadrangle: South Dakota Geological Sur­ Bulletin 14A, 82 p. vey Geologic Map, scale 1:62,500. Cronin, J.G., and Newport,T. G., 1956, Ground­ Barbour. E.H.. and Cook. H.J.. 1917. Skull of water resources of theAinsworth unit, Cherry Aelurodon platyrhinus sp. nov.: Nebraska and Brown Counties. Nebraska: U.S. Geo­ Geological Survey, v. 7, pt. 19, p. 173-180. logical Survey Water-Supply Paper 1371, Burchett, R.R. (compiler) , 1986, Geologic 120 p. bedrock map of Nebraska: University of Ne­ Darton , N.H. , 1899, Geology and water re­ braska , Conservation and Survey Division , sources of Nebraska west of the one hun­ scale 1:1,000,000. dred and third meridian: U.S. Geological Burchett, R. R., Dreeszen , V. H., Souders , v.L., Survey 19th Annual Repo 时 ， pt. 4, p. 719­ and Prichard , G.E., 1988, Bedrock geologic 785. map showing configuration of the bedrock DeGraw. H.M.. 1975. The Pierre-Niobrara surface in the Nebraska part of the Sioux unconformity in western Nebraska: Geologi­ City 1° x 2° quadrangle: U.S. Geological Sur­ cal Association of Special Paper 13, vey Miscellaneous Investigations Series p.589-606. Map 1-1879, scale 1:250,000. Dietrich. E.S.. 1951. A zonation of the Pierre Carlson , M.P. , 1993, Geology, geologic time Shale of western Nebraska based on fossil and Nebraska: University of Nebraska, Con­ foraminifera: Lincoln, University of Nebraska servation and Survey Division , Educational M.S. thesis , 91 p. Circular 10, 58 p. Diffendal, R.F. , Jr., 1993, Geologic mapping of Cast, L. D., 1988, Geological engineering as­ Nebraska, 1845-1993: University of Ne­ sessment of Verdigre damsite-Knox County, braska , Conservation and Survey Division , Nebraska: U.S. Bureau of Reclamation Ge­ Resource Notes, v. 7, p. 3-6. ology Files, 10 p. Engelmann , H., 1876: Report on the geology Christensen , C.M., 1974, Geology and water of the country between Fort Leavenworth , resources of Bon Homme County, South Da­ K.T.. and the Sierra Nevada. near Carson kota-Part I (Geology): South Dakota Geo­ Valley: in Simpson , J.H. , Report on explora­ logical Survey Bulletin 21 , 48 p. tions across the of the Territory 9 of Utah for a direct wagon-route from Camp 221 , p. 364-366. Floyd to Genoa, in Carson Valley, in 1859, Indra, 0., 1979, Soil survey of Boyd County, p.243-336. Nebraska: USDA Soil Conservation Service Evander, R.L. , 1978, Rocks and faunas of the 173 p. type section of the Valentine Formation: Lin­ Johnson, F. W., 1936, The status of the name coin , University of Nebraska M.S. thesis, "Valentine" in Tertiary geology and paleon­ 223 p. tology: American Journal of Science, v. 31 , Flint , R.F., 1955, Pleistocene geology of east­ p.467-475. ern South Dakota: U.S. Geological Survey Johnson, F. W., 1938, Further comments on the Professional Paper 262 , 173 p. usage of "Valentine": American Journal of Gosselin. D.C.. coordinator. 1991. Bazile Tri­ Science, v. 36 , p. 215-219. angle groundwater quality study: University Johnson. G.D.. and Milburn. SF. 1984. Patho­ of Nebraska, Conservation and Survey Di­ logical evidence of an injured equid, and as­ vision Water Survey Paper 68, 29 p. sociated fossils of late Blancan (?) age from Guthrie, R.S. , 1990, The geology and distribu­ the Bon Homme Gravel, Yankton County, tion of oriented landforms and associated South Dakota: Proceedings of the South Da­ features in northeastern Nebraska: Lincoln kota Academy of Sciences, v. 63 , p. 77-84 University of Nebraska Ph.D. dissertation, Landon, J., 1985, Xylum water stress analy­ 125 p. sis--A new method for studying paleo-envi­ Haffner. J.. Gabel. M.L.. and Tieszen. L.L. ronments: Lincoln, University of Nebraska 1990, Stable carbon isotope ratios of Mi­ M.S. thesis, 38 p. ocene sediments and fossil Cθ I tis (Ulm­ Loetterle, G.J. , 1937, The micropaleontology Bθ rrioch loa aceae) and (Gramineae) repro­ of the Niobrara Formation in , Ne­ ductive structures from the northern Great braska. and South Dakota: Nebraska Geo­ Plains: South Dakota Academy of Sciences logical Survey Bulletin 12, 73 p. Proceedings, v. 69 , p. 145-152. Lugn, A.L., 1938, The Nebraska State Geo­ Hedges, L.S., 1975, Geology and water re­ logical Survey and the "Valentine problem": sources of Charles Mix and Douglas coun­ American Journal of Science, v. 36 , p. 220­ ties , South Dakota--Part I (Geology): South 227. Dakota Geological Survey Bulletin 22 , 43 p. Lugn , A.L. , 1939, Classification of the Tertiary Hunt, R. M., Jr., 1978, Depositional setting of System in Nebraska: Geological Society of a Miocene mammal assemblage, Sioux America Bulletin , v. 50 , p. 1245-1276. County, Nebraska (U.S. A. ): Palaeogeog­ Manhke, C., Hammers, R., Hammond, C., and raphy, Palaeoclimatology, Palaeoecology, v. Shulte, R., 1978, Soil survey of Antelope 24 , p. 1-52. County, Nebraska: USDA Soil Conservation Hunt, R. M., Jr., 1990, Taphonomy and sedi­ Service, 128 p. mentology of Arikaree (lower Miocene) flu­ Matthew, W.D. and Gidley, J.W. , 1904, New or vial , eolian , and lacustrine paleoen­ little-known mammals from the Miocene of vironments, Nebraska and Wyoming--A South Dakota: American Museum of Natu­ paleobiota entombed in fine-grained ral History Bulletin, v. 20 , p. 241-268. volcaniclastic rocks , in Lockley, M.G. , and Meek, F. B., and Hayden, F. V., 1858, Descrip­ Rice, A., eds. , Volcanism and fossil biotas: tion of new species and genera of fossils...: Boulder, Colorado, Geological Society of PhiladelphiaAcademy of Sciences Proceed­ America Special Paper 244 , p. 69-111. ings , v. 9, p. 117-148. Hunt, R. M., Jr., Xiang-Xu, Xue , and Kaufman, Meek, F. B., and Hayden, F.V. , 1862, Descrip­ J.. 1983. Miocene burrows of extinct bear tion of new lower (Primordial), Ju­ dogs--Indication of early denning behavior rassic , Cretaceous, and Tertiary fossils col­ of large mammalian carnivores: Science, v. lected in NebraskaTerr...: PhiladelphiaAcad- 10 emy of Sciences Proceedings , v. 13, p. 415­ 1:62.500. 447. Schulte, J.J., 1952, The bedrock geology of Mendenhall, G.v., 1953, The bedrock geology Knox County, Nebraska: Lincoln, University of Boyd and northern Holt counties, Ne­ of Nebraska M.S. thesis , 98 p. braska: Lincoln, University of Nebraska M.S. Schulte, R.B., in press, Soil survey of Knox thesis , 107 p. County, Nebraska: USDA Soil Conservation Newport , T. G., 1959, Ground-water resources Service. of the lower Niobrara River and Ponca Creek Shu 时 | 肝 ， D.R., Ragon, L.G., Seevers , V. C., and basins , Nebraska and South Dakota: U.S. Belohlavy, F., 1988, Soil survey of Garfield Geological Survey Water-Supply Paper County, Nebraska: USDA Soil Conservation 1460-G , p. 273-323. Service, 182 p. Niobrara River Basin Development Associa­ Shu 时Ii 忏 ， D.R., Seevers , V. C., and Belohlavy, tion, 1951: Niobrara River Basin Develop­ F.v., 1990, Soil Survey of Loup County, Ne­ ment Association , fifth annual meeting pro­ braska: USDA Soil Conservation Service gram , 21 p. 190 p. Pabian, R.K., 1979, Record in rock: University Simpson , H.E., 1960, Geology of the Yankton of Nebraska , Conservation and Survey Di­ area. South Dakota and Nebraska: U.S. vision , Educational Circular 1, 99 p. Geological Survey Professional Paper 328, Pierce, H.G., 1989, The hydrogeology of Can­ 124 p. didate Site A, Boyd County, Nebraska…Low Skinner, M.F., and Hibbard , C.W., 1972, Early level radioactive waste storage facility…Cen• Pleistocene pre-glacial and glacial rocks and teal Interstates Compact: Unpublished Re­ faunas of north-central Nebraska: American po 叫to Boyd County LLRW monitoring com­ Museum of Natural History Bulletin , v. 148, mittee, Nebraska , 9 p. a 时.1 ，p.1-148. Pinsof, J.D., 1985,The Pleistocene vertebrate Skinner, M.F. , and Johnson ， 仨W. ， 1984, Ter­ localities of South Dakota: Dakoterra , v. 2, tia 叩stratigraphy and the Frick Collection of pt. 2, p. 233-264. fossil vertebrates from north-central Ne­ Plantz, M., and Zink, R., 1980, Soil survey of braska: American Museum of Natural His­ Keya Paha County, Nebraska: USDA Soil tory Bulletin, v. 178, art. 3, p. 215-368. Conservation Service , 224 p. Skinner, M.F., Skinner, S.M., and Gooris , R.J., Ragon , L.G. , Seevers, V.C. , Indra, 0. , 1968, Cenozoic rocks and faunas of Turtle Belohlavy, F. , Lobaugh, S.J., Carlson , J., Butte, south-central South Dakota: Ameri­ Schultz, H. 1983, Soil survey of Holt County, can Museum of Natural History Bulletin , v. Nebraska: USDA Soil Conservation Service, 138, art. 7, p. 379-436. 307 p. Skinner, M.F., Skinner, S.M., and Gooris , R.J., Rahn, PH. , and Davis, A. D., 1989, Hydroge­ 1977, Stratigraphy and biostratigraphy of ology of the proposed low-level radioactive late Cenozoic deposits in central Sioux waste site in Boyd County, Nebraska: Un­ County, western Nebraska: American Mu­ published report to Boyd County LLRW seum of Natural History Bulletin, v. 158, art. monitoring committee , 39 p. 5, p. 263-371. Reed, E.C., 1944, Groundwater survey of area Skinner, M. 仨 ， and Taylor, B.E., 1967, A revi­ north of O'Neill, Holt County, Nebraska: sion of the geology and paleontology of the University of Nebraska , Conservation and Bijou Hills, South Dakota:American Museum Survey Division , Water Survey Paper 2, of Natural History Novitates , no. 2300 , 53 p. 26 p. Souders , v.L., 1976, Physiography, geology, Schoon, R.A., and Sevon, W.D., 1958, Geol­ and water resources of Boyd County, Ne­ ogy of the Keyapaha quadrangle: South Da­ braska: University of Nebraska, Conserva­ kota Geological Survey Geologic Map, scale tion and Survey Division , Water Survey Pa-

11 per 42,113 p. vation and Survey Division , Resource Atlas Souders , VL. , 1981, Geology and groundwa­ 5a, p. 29-42. ter supplies of southern Dawes and north­ Swinehart , J.B., Souders , V L. , DeGraw, H.M., ern Sheridan counties, Nebraska: University and Diffendal, R.F., J 仁 ， 1985, Cenozoic pa­ of Nebraska, Conservation and Survey Di­ leogeography of western Nebraska, in vision, Open-File Report No. 29, 125 p. Flores, R.M., and Kaplan, S.S, eds., Ceno­ Souders , VL., and Shaffer ， 仨B. ， 1969, Water zoic paleogeography of west-central United resources of Antelope County, Nebraska: States: Society of Economic Paleontologists U.S. Geological Survey HydrologicAtlas HA­ and Mineralogists, Rocky Mountain Section 316,3 pis. Paleogeography Symposium 3, p. 209-229. Stanley, K.O., 1971, Areal and temporal differ­ Todd, J.E., 1912, Pre-Wisconsin channels in ences in Plio-Pleistocene gravel composi­ southeastern South Dakota and northeast­ tion, Nebraska, in Stout,TM. , DeGraw, H.M., ern Nebraska: Geological Society ofAmerica Tanner, L.G., Stanley, K.O., Wayne, W.J., Bulletin, v. 23, p. 463-470. and Swinehart, J.B., Guidebook to the late U.S. Bureau of Reclamation-Region 7, 1952, Pliocene and early Pleistocene of Nebraska: Missouri River Basin Project-Niobrara River University of Nebraska , Conservation and Basin, Nebraska , Wyoming , South Dakota: Survey Division , p. 22-27. U.S. Department of the Interior, Denver, Stanley, K.O. , and Wayne, W.J. , 1972, Colorado , iv + 30 + 2 + 200 p. Epirogenic and climatic controls of early U.S. Bureau of Reclamation--Region 7, 1962, Pleistocene fluvial sediment dispersal in Report on the o'r\Jeill Unit, Nebraska, Part Nebraska: Geological Society of America 1: U.S. Department of the Interior, Denver, Bulletin, v. 83, p. 3675-3690. Colorado , 97+ p. Stevenson , R.E., and Carlson , L.A., 1950, Ar­ U.S. Bureau of Reclamation, 1977, O'Neill Unit, eal geology of the Bonesteel quadrangle: Lower Niobrara Division , Pick-Sloan Mis­ South Dakota Geological Survey Geologic souri Basin Program , Nebraska, Supple­ Map, scale 1:62,500. ment, Appendix A, Geologic Data: U.S. De­ Stevenson , R.E., and Carlson , L.A., 1951, Ar­ partment of the Interior, 4 p. and attach­ eal geology of the Lake Andes quadrangle: ments. South Dakota Geological Survey Geologic U.S. Bureau of Reclamation, 1978, O'Neill Unit, Map, scale 1:62,500. Lower Niobrara Division , Pick-Sloan Mis­ Stevenson , R.E., Hale, R.L., and Skagstrom , souri Basin Program, Nebraska, Supple­ H.C. , Jr., 1958 , Geology of the Gregory ment: U.S. Department of the Interior, 4 p. quadrangle: South Dakota Geological Sur­ and 9 chapters. vey Geologic Map, scale 1:62,500. U.S. Bureau of Reclamation, 1980, O'Neill Unit, Stevenson, R.E., Skagstrom, H.C., Jr., and Lower Niobrara Division , Pick-Sloan Mis­ Harksen, J.C., 1959, Geology of the Dallas souri Basin Program , Nebraska , Final Envi­ quadrangle: South Dakota Geological Sur­ ronmental Statement Supplement NO.2: vey Geologic Map, scale 1:62,500. U.S. Department of the Interior, 236 口 ，3 Swinehart , J. 日 ， 1990, Wind-blown deposits , attachments , and 2 appendices. in Flowerday, C.F., and Bleed,A.S., eds. ,An U.S. Bureau of Reclamation, 1992, O'Neill Unit Atlas of the Sand Hills: University of Ne­ Pick-Sloan Missouri Basin Program, Ne­ braska , Conservation and Survey Division, braska, Special report-Ground-water re­ Resource Atlas 5a, p. 43-56. charge plan: U.S. Department of the Inte­ Swinehart, J.B., and Diffendal, R.F. , Jr., 1990, rior, Kansas-Nebraska Projects Office, 90 p. Geology of the pre-dune strata, in Flowerday, and attachments. C.F. , and Bleeds, A.S., eds., An Atlas of the U.S. Soil Conservation Service, 1973, Niobrara Sand Hills: University of Nebraska , Conser- River basin--Nebraska water and related

12 land resources: U.S. Department of Agricul­ Nebraska, in Biggs , D.L., ed. , North-Central ture , xi + 147 p. Section Centennial Field Guide: Geological U.S. Water and Power Resources Service, Society of America Centennial Field Guide , 1980 , O'Neill Unit, Lower Niobrara Division , v. 3, p. 1-6. Pick-Sloan Missouri Basin Program , Final Voorhies , M.R. , 1990a, Nebraska wildlife--Ten Environmental Statement, Supplement No. million years ago: Nebraskaland, v. 68, no. 2, Appendix A, Geologic Stability: U.S. De­ 5,p.8-17. partment of the Interior, 6 reports, 3 sets of Voorhies , M.R., 1990b, Vertebrate biostratig­ logs , 12 sets of tests , and sections, etc. raphy of the Ogallala Group in Nebraska, in Voightlander, A. L., Hammer, R.R. , Zink , R.R. , Gustavson , T. C., ed. , Geologic Framework Babcock, M.K.,Evans, B.C., Patterson , M.D., and Regional Hydrology-Upper Cenozoic Schultz, H. , 1992, Soil survey of Brown Blackwater Draw and Ogallala Formations, County, Nebraska: USDA Soil Conservation Great Plains: Bureau of Economic Service, 272 p. Geology, p. 115-151. Voorhies , M.A. , 1969, Taphonomy and popu­ Voorhies , M.R. , 1990c, Vertebrate paleontol­ lation dynamics of an early Pleistocene ver­ ogy of the proposed Norden Reservoir area , tebrate fauna , Knox County, Nebraska: Uni­ Brown , Cherry, and Keya Paha counties, versity of Wyoming Contributions to Geol­ Nebraska: University of Nebraska, Division ogy Special Paper 1, 69 p. of Archeological Research Technical Report Voorhies, M.R. , 1971 , Paleoclimatic signifi­ 82-09 , p. 1-138 , A1-A593. cance of crocodilian remains from the Voorhies, M.A. , and Goodwin , R.G., 1989, Plio­ Ogallala Group (upperTertiary) in northeast­ Pleistocene glacial deposits in northeastern ern Nebraska: Journal of Paleontology, v. 45, Nebraska: New exposures and interpreta­ p. 119-121. tions: Nebraska Geological Society spring Voorhies , M.R., 1973, Early Miocene mammals field trip guidebook, 30 p. from northeast Nebraska: University of Wyo­ Wellstead , C. F. , 1981 , Sedimentology of ming Contributions to Geology, v. 12, p. 1­ Norden Bridge and Egelhoff fossil quarries 10. (Miocene) of north-central Nebraska: Ne­ Voorhies, M.R. , 1974 , Fossil pocket mouse braska Academy of Sciences Transactions, burrows in Nebraska: American Midland v. 9, p. 67-85. Naturalist, v. 91, p. 492-498. Williams, R.H., 1984, Provenance study of late Voorhies , M.R., 1981, Ancient ashfall creates Cenozoic sand and gravel deposits in north­ a Pompeii of prehistoric animals: National eastern Nebraska: Lincoln, University of Ne­ Geographic, v. 159, no. 1, p. 66-75. braska M.S. thesis, 86 p. Voorhies , M.R., 1985, A Miocene rhinoceros Yatkola, D. A., 1978, Tertiary stratigraphy of herd buried in volcanic ash: National Geo­ the Niobrara River valley, Marsland quad­ graphic Society Research Reports , v. 19, p. rangle, western Nebraska: University of 671-688. Nebraska, Conservation and Survey Divi­ Voorhies, M.R. , 1987a, Fossil armadillos from sion, Nebraska Geological Survey Paper No. Nebraska--The northernmost record: South­ 19,66 p. + 6 pis. western Naturalist, v. 32, p. 237-243. Zink , R.R. , and Schultz, H., 1985 , Soil survey Voorhies , M.R., 1987b, Late Cenozoic stratig­ of Rock County, Nebraska: USDA Soil Con­ raphyand geomorphology, , servation Service, 168 p.

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