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Overview Of Nebraska And The Regional Aquifer From Proceedings Of The 1985 Water Resources Seminar Series, Robert F. Diffendal Jr. Jun 1985

Overview Of Nebraska And The Regional Aquifer From Proceedings Of The 1985 Water Resources Seminar Series, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

During each spring semester, the Nebraska Water Resources Center sponsors a Water Resources Seminar Series at the University of Nebraska-Lincoln. The 1985 seminar series was entitled "Aspects of Groundwater Quality." This article appeared in the proceedings.


Cenozoic Paleogeography Of Western Nebraska, James B. Swinehart, Vernon F. Souders, Harold M. Degraw, Robert F. Diffendal Jr. Jan 1985

Cenozoic Paleogeography Of Western Nebraska, James B. Swinehart, Vernon F. Souders, Harold M. Degraw, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The Cenozoic strata of western Nebraska are an extensive sequence of continental deposits that extend eastward from the Hartville, Laramie, and Front Range uplifts and southeast from the Black Hills. The oldest Cenozoic sediments (Chadron Formation, White River Group) are Early Oligocene alluvial valley fills. Subsequent to filling of these drainages and continuing for about the next 7 million years, landscape development in western Nebraska was dominated by eolian deposition of tremendous volumes of rhyolitic volcanic ash derived from western eruptions. A plain of low relief, with only an occasional narrow drainage heading in the western highlands, was maintained during …


Keith County, Nebraska, Map Series, Robert F. Diffendal Jr., Mark S. Kuzila, J. R. Culver, Harold M. Degraw, R. R. Burchett, M. P. Carlson, T. Eversoll, William D. Gosnold, Nebraska Geological Survey Jan 1985

Keith County, Nebraska, Map Series, Robert F. Diffendal Jr., Mark S. Kuzila, J. R. Culver, Harold M. Degraw, R. R. Burchett, M. P. Carlson, T. Eversoll, William D. Gosnold, Nebraska Geological Survey

Robert F. Diffendal, Jr., Publications

Keith County--List of Maps and Their Authors

Topography--United States Geological Survey

Index of 7.5' Topographic Quadrangles and Township Boundaries--R. F. Diffendal, Jr.

Generalized Soils Map--M. Kuzila and J. Culver

Approximate Loess Thickness--R. F. Diffendal, Jr.

Bedrock Geologic Map--R. F. Diffendal, Jr.

Volcanic Ash Localities--R. F. Diffendal, Jr.

Ogallala Vertebrate Faunal Sites--R. F. Diffendal, Jr.

Ogallala Group Outcrops--R. F. Diffendal, Jr.

White River Group Outcrops--R. F. Diffendal, Jr.

Conservation and Survey Division Test Hole Locations--R. F. Diffendal, Jr.

Oil and/or Gas Test Hole Locations--R. F. Diffendal, Jr.

Mineral Resources Localities--R. F. Diffendal, Jr.

Locations of Registered Irrigation Wells--R. F. Diffendal, Jr. …


Armored Mud Balls And Friable Sand Megaclasts From A Complex Early Pleistoceme Alluvial Fill, Southwestern Morrill County, Nebraska, Robert F. Diffendal Jr. Jan 1984

Armored Mud Balls And Friable Sand Megaclasts From A Complex Early Pleistoceme Alluvial Fill, Southwestern Morrill County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Armored mud balls and friable sand megaclasts occur in exposures of a complex Early Pleistocene sand and gravel alluvial fill which caps a strath terrace in southwestern Morrill County, Nebraska. The mudballs are limited to a tributary arroyo. The sand megaclasts occur in sediments deposited along a trunk stream. It is possible that the sand megaclasts were transported to the site in a frozen condition.


Cenozoic Geology Of The Southern Nebraska Panhandle: Old Valleys, Volcaniclastics, And Vertebrates: 1984 Fall Field Trip, Nebraska Geological Society, James B. Swinehart, Robert F. Diffendal Jr., Mary Rebone, Robert Hunt Jan 1984

Cenozoic Geology Of The Southern Nebraska Panhandle: Old Valleys, Volcaniclastics, And Vertebrates: 1984 Fall Field Trip, Nebraska Geological Society, James B. Swinehart, Robert F. Diffendal Jr., Mary Rebone, Robert Hunt

Robert F. Diffendal, Jr., Publications

Two-day field trip:

Duer Ranch Locality, Morrill County, Nebraska

The Duer Ranch locality contains some of the finest and most easily accessible examples of different styles of alluvial cuts and fills in the Cenozoic of Nebraska. It offers a unique area in which to examine the geometries and alluvial fills of several Miocene and Pliocene age paleovalleys and paleogullies. Good exposures of eolian volcaniclastic siltstones and a regionally important volcanic ash of the Oligocene age Brule Formation are also present at the Duer Ranch locality.

Early Miocene Mammals and Lithostratigraphy of the Indian Creek Drainage, Near Bridgeport, Morrill County, Western …


Megaclasts In Alluvial Fills From The Ogallala Group (Miocene), Banner, Kimball, And Morrill Counties, Nebraska, Robert F. Diffendal Jr. Oct 1983

Megaclasts In Alluvial Fills From The Ogallala Group (Miocene), Banner, Kimball, And Morrill Counties, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Locally derived blocks and boulders (megaclasts) occur in conglomerate and in sand and gravel fills of channels in the Ogallala Group (Miocene) at localities in Banner, Kimball, and Morrill counties in western Nebraska. Some of the megaclasts are up to one or more orders of magnitude larger than the largest distantly derived grains in the sediments surrounding them. A number of these megaclasts probably moved downslope by mass wasting from outcrop sites on paleovalley sides and were later transported by running water. Other blocks and boulders were eroded by streams from bedrock along channel sides and then were transported by …


An Irvingtonian Fauna From The Oldest Quaternary Alluvium In Eastern Pumpkin Creek Valley, Morrill And Banner Counties, Nebraska, R. George Corner, Robert F. Diffendal Jr. May 1983

An Irvingtonian Fauna From The Oldest Quaternary Alluvium In Eastern Pumpkin Creek Valley, Morrill And Banner Counties, Nebraska, R. George Corner, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Vertebrate fossils of Mammuthus meridionalis (Nesti) and Equus sp. cf. E. scotti Gidley occur at two sites in the capping alluvium of the highest strath terrace along the south side of Pumpkin Creek Valley, Nebraska. The presence of these two species supports the conclusion that the age of the capping sediments is probably early Irvingtonian (early Pleistocene).


Asymmetrical Distribution Of Quaternary Alluvial Fills, Pumpkin Creek Drainage Basin, Western Nebraska, Robert F. Diffendal Jr., R. George Corner Jan 1983

Asymmetrical Distribution Of Quaternary Alluvial Fills, Pumpkin Creek Drainage Basin, Western Nebraska, Robert F. Diffendal Jr., R. George Corner

Robert F. Diffendal, Jr., Publications

A remnant alluvial fill of early Pleistocene age exposed in Pumpkin Creek Valley, Banner and Morrill counties, Nebraska, has yielded fossils of Mammuthus meridionalis (Nesti) and Equus sp. cf. E. scotti Gidley. Younger fill remnants of trunk and tributary streams allow a refinement of earlier views on the development of the Pumpkin Creek drainage basin during the Quaternary Period. Ancestral Pumpkin Creek both shifted to the north and entrenched its valley several times during the Quaternary Period leaving alluvial fills at three levels or more south of the present creek. Piracy of the headwaters of ancestral Pumpkin Creek took …


Gully, Scour Hole, And Pothole Development At The Base Of The Gering Formation (Miocene?), Southeastern Banner County, Nebraska, Robert F. Diffendal Jr. Sep 1982

Gully, Scour Hole, And Pothole Development At The Base Of The Gering Formation (Miocene?), Southeastern Banner County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Several sediment-filled paleovalleys belonging to the Arikaree Group of Miocene (?) age occur in southeastern Banner County, Nebraska. One gully and a main paleovalley exhibit, respectively, erosional features like those in modern gullies in the area and like those on the bedrock floors of modern straight streams carrying an appreciable sediment load. Scour holes and a pothole on the valley floor of the main paleovalley are similar to those produced experimentally on the bed of a straight stream.


Harrisburg Quadrangle, Banner County, Nebraska, Robert F. Diffendal Jr. Jan 1982

Harrisburg Quadrangle, Banner County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 30' — 41° 37'30"

103° 37'30" — 103° 45'

Scale 1:24,000

Completed May 10, 1982 (?)

High resolution .tif file attached below as supplemental file


Regional Implications Of The Geology Of The Ogallala Group (Upper Tertiary) Of Southwestern Morrill County, Nebraska, And Adjacent Areas, Robert F. Diffendal Jr. Jan 1982

Regional Implications Of The Geology Of The Ogallala Group (Upper Tertiary) Of Southwestern Morrill County, Nebraska, And Adjacent Areas, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

A part of a filled Ogallala Group (upper Tertiary) paleovalley system exhumed by recent stream erosion in southwestern Morrill County, Nebraska, and adjacent areas contains steep gradient gullies filled with locally derived sediments. Younger channels filled with granitic gravels derived by stream erosion of the Rocky Mountains to the west and southwest cut across and through these older filled gullies, indicating that there were at least two periods of downcutting followed by periods of filling during the development of this system.

Individual clasts from younger Ogallala gravels are often as large as or larger than clasts from Quaternary gravels transported …


Gravity And Ground Magnetic Investigations In Eastern Nebraska, Robert F. Diffendal Jr., R. R. Burchett Nov 1981

Gravity And Ground Magnetic Investigations In Eastern Nebraska, Robert F. Diffendal Jr., R. R. Burchett

Robert F. Diffendal, Jr., Publications

The purpose of this investigation was to extend the area covered by gravity and ground magnetic data related to the Nemaha Uplift and associated structures in eastern Nebraska. Gravity data were collected from Clay, Fillmore, Hamilton, Nuckolls, Polk, Thayer, and York Counties. Additional ground magnetic data and gravity data were collected for central Otoe County.


Gravity And Ground Magnetic Investigations In Eastern Nebraska, Robert F. Diffendal Jr., R. R. Burchett Sep 1981

Gravity And Ground Magnetic Investigations In Eastern Nebraska, Robert F. Diffendal Jr., R. R. Burchett

Robert F. Diffendal, Jr., Publications

The purpose of this investigation was to extend the area covered by gravity and ground magnetic data related to the Nemaha Uplift and associated structures in eastern Nebraska. Gravity data were collected from Butler, Jefferson, Saline, and Seward counties. Additional ground magnetic data and gravity data were collected for eastern Sarpy and northeastern Cass counties in Nebraska and gravity data were collected from parts of Mills and Fremont counties in Iowa.


Ash Hollow Historical Park, Robert F. Diffendal Jr. May 1980

Ash Hollow Historical Park, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Ash Hollow Creek is an intermittent stream forming a southern tributary to the North Platte River. The creek flows only in response to precipitation from locally heavy thunderstorms or to heavy runoff from melting snow in the spring. Western Nebraska has a semi-arid climate and receives less than 20 inches of rainfall per year. Vegetation in the park and surrounding area is typical of the short grass prairie of the Great Plains. Native short grasses grow abundantly on undisturbed tablelands, valley sides, and along principal flood plains of streams and rivers. Prickly pear, barrel cactus, yucca and sagebrush are common …


Broadwater Ne Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr. May 1979

Broadwater Ne Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 37'30" — 41° 45'

102° 45' — 102° 52'30"

Scale 1:24,000

Completed June 6, 1979

High resolution .tif file attached below as supplemental file


Broadwater Nw Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr. Jan 1979

Broadwater Nw Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 37'30" — 41° 45'

102° 52'30" — 103° 00'

Scale 1:24,000

Completed June 25, 1979

High resolution .tif file attached below as supplemental file


Glinn Ranch Quadrangle, Keith County, Nebraska, Robert F. Diffendal Jr. Sep 1978

Glinn Ranch Quadrangle, Keith County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 15' — 41° 22'30"

101° 30' — 101° 37'30"

Scale 1:24,000

Completed September 20, 1978

High resolution .tif file attached below as supplemental file


Martin Quadrangle, Nebraska—Keith County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Sep 1978

Martin Quadrangle, Nebraska—Keith County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Martin Quadrangle, Nebraska—Keith County

7.5 minute series (topographic), scale 1:24,000

101°37'30" to 101°45'

41°15' to 41°22'30"

Ogallala Group

Completed September 20, 1978


Ogallala Sw Quadrangle, Nebraska—Keith And Perkins Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Sep 1978

Ogallala Sw Quadrangle, Nebraska—Keith And Perkins Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Ogallala SW Quadrangle, Nebraska—Keith and Perkins Counties

7.5 minute series (topographic), scale 1:24,000

101°37'30" to 101°45'

41°00' to 41°07'30"

Post-Ogallala sand and gravel

September 20, 1978


Brule Se Quadrangle, Keith And Perkins Counties, Nebraska, Robert F. Diffendal Jr. Sep 1978

Brule Se Quadrangle, Keith And Perkins Counties, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 00' — 41° 07'30"

101° 45' — 101° 52'30"

Scale 1:24,000

High resolution .tif file attached below as supplemental file


Brule (Sw) Quadrangle, Keith And Perkins Counties, Nebraska, Robert F. Diffendal Jr. Sep 1978

Brule (Sw) Quadrangle, Keith And Perkins Counties, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 00' — 41° 07'30"

101° 52'30" — 102° 00'

Scale 1:24,000

High resolution .tif file attached below as supplemental file


Green Ranch Quadrangle, Lincoln County, Nebraska, Robert F. Diffendal Jr. Jul 1978

Green Ranch Quadrangle, Lincoln County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

41° 15' — 41° 22'30"

101° 00' — 101° 07'30"

Scale 1:24,000

Completed July 11, 1978

High resolution .tif file attached below as supplemental file


Sutherland Reservoir Nw Quadrangle, Nebraska—Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Jul 1978

Sutherland Reservoir Nw Quadrangle, Nebraska—Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Sutherland Reservoir NW Quadrangle, Nebraska—Lincoln Co.

7.5 minute series (topographic), scale 1:24000

101°07'30" to 101°15'

41°07'30" to 41°15'

Ql = Loess, Post-Ogallala Sand and Gravel, Ogallala Outcrop

July 11, 1978


Nevens Quadrangle, Nebraska—Keith County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Jul 1978

Nevens Quadrangle, Nebraska—Keith County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Nevens Quadrangle, Nebraska—Keith County

7.5 minute series (topographic), scale 1:24,000

101°22'30" to 101°30'

41°07'30" to 41°15'

Ql = Loess

Post-Ogallala sand and gravels

Ogallala Outcrop

Volcanic ash

July 11, 1978


Paxton North Quadrangle, Nebraska—Keith And Lincoln Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Jul 1978

Paxton North Quadrangle, Nebraska—Keith And Lincoln Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Paxton North Quadrangle, Nebraska—Keith and Lincoln Counties

7.5 minute series (topographic), scale 1:24000

101°15' to 101°22'30"

41°07'30" to 41°15'

Ql=loess, Qsa=sand; Post-Ogallala sand and gravel; Ogallala Outcrop

July 7, 1978


Hershey West Quadrangle, Lincoln County, Nebraska, Robert F. Diffendal Jr. Jun 1978

Hershey West Quadrangle, Lincoln County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5' topgraphic quadrangle showing exposures of bedrock formations and other geologic information.

101° 00' — 101° 07'30"

41° 07'30" — 41° 15'

Scale 1:24,000

Completed July 11, 1978

High resolution .tif file attached below as supplemental file


Maxwell Quadrangle, Nebraska—Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Jun 1978

Maxwell Quadrangle, Nebraska—Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Maxwell Quadrangle, Nebraska—Lincoln County

7.5 minute series (topographic), scale 1:24,000

100°30' to 100°37'30"

41°00' to 41°07'30"

Ogallala Outcrop

Completed June 7, 1978


Twin Buttes Quadrangle, Nebraska—Garden County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Aug 1977

Twin Buttes Quadrangle, Nebraska—Garden County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Twin Buttes Quadrangle, Nebraska—Garden Co.

7.5 minute series (topographic), scale 1:24000

102°07'30" to 102°15'

41°07'30" to 41°30'

Qsa, Ql, Qg, Ogallala Outcrop, Ogallala Volcanic Ash, Pre-Ogallala (Brule) Outcrop, Pre-Ogallala (Brule) White Horizons, QF=Pleist Fossil, BF=Brule Fossil, F-Ogallala Fossil

August 28, 1977


Lisco Se Quadrangle, Nebraska—Garden And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Aug 1977

Lisco Se Quadrangle, Nebraska—Garden And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Lisco SE Quadrangle, Nebraska—Garden and Cheyenne Counties

7.5 minute series (topographic), scale 1:24,000

102°30' to 102°37'30"

41°15' to 41°22'30"

Ql = Loess

Qsa = Sand

Volcanic ash

Completed August 27, 1977


Oshkosh Quadrangle, Nebraska—Garden County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Aug 1977

Oshkosh Quadrangle, Nebraska—Garden County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Oshkosh Quadrangle, Nebraska—Garden County

7.5 minute series (topographic), scale 1:24000

102°15' to 102°22'30"

41°22'30" to 41°30'

Ogalalla Outcrop, Pre-Ogallala Outcrop, Brule-Whitney

August 5, 1977