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Full-Text Articles in Geology

Geologic Map Of The Scottsbluff, 1 ° X 2 ° Quadrangle, Nebraska And Colorado, James B. Swinehart, Robert F. Diffendal Jr. Jan 1997

Geologic Map Of The Scottsbluff, 1 ° X 2 ° Quadrangle, Nebraska And Colorado, James B. Swinehart, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

This map is necessarily generalized. For more detailed information, consult the geologic data stored in files of the Conservation and Survey Division, University of Nebraska-Lincoln. Other geologic maps at different scales that include all or parts of the map area are by Darton (1903a,b,c), Lugn (1939), Weeks and Gutentag (1981), and Weeks and otners (1988). Detailed groundwater investigations of parts of the map area were done by Wenzel and others (1946). Babcock and Visher (1951, 1952), Bjorklund (1957), Bjorklund and Brown (1957), Smith (1966, 1969), Smith and Souders (1971,1975). Souders (1986), Gottula (1993), and Verstraeten and others (1995).

Introduction

The …


Geology And Ground Water, Cheyenne County, Nebraska, Robert F. Diffendal Jr. Jan 1997

Geology And Ground Water, Cheyenne County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The oldest rock unit exposed in Cheyenne County is the upper part of the Brule Formation, which is the youngest formation of the White River Group of the Oligocene epoch (33-29 million years old). Surface outcrops, road cuts, and railroad cuts through the Brule Formation occur along the sides of valleys along Lodgepole Creek from just east of Sidney westward to the vicinity of Brownson, along the valley sides of Sidney Draw and its tributaries, and along the sides of an unnamed drainageway northwest of Colton. Test drilling and drilling for wells along the floor of Lodgepole Creek have revealed …


Geology Beneath The Primary Management Systems Evaluation Area (Msea) Site Southwest Of Shelton, Buffalo County, Nebraska, Robert F. Diffendal Jr., Frank A. Smith Feb 1996

Geology Beneath The Primary Management Systems Evaluation Area (Msea) Site Southwest Of Shelton, Buffalo County, Nebraska, Robert F. Diffendal Jr., Frank A. Smith

Robert F. Diffendal, Jr., Publications

In 1990, as part of a national presidential initiative on water quality, researchers from the University of Nebraska–Lincoln (UNL) Institute of Agriculture and Natural Resources (IANR) received a multiyear grant from the U.S. Department of Agriculture, Cooperative State Research Service, to study management of irrigated corn and soybeans to minimize groundwater contamination. D. G. Watts, R. F. Spalding, and J.S. Schepers, of the IANR led a study at one of the Management Systems Evaluation Areas (MSEA). This area was made up of two sites, a primary site on a terrace of the Platte River near Shelton and a secondary site …


Geology Of The Ogallala/High Plains Regional Aquifer System In Nebraska: Field Trip No. 6, Robert F. Diffendal Jr. Apr 1995

Geology Of The Ogallala/High Plains Regional Aquifer System In Nebraska: Field Trip No. 6, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

This guide is mostly figures with a reference section containing some of the pertinent literature on the Cenozoic geology we will see over the next four days. We will make all 17 stops if the weather is reasonably good and the roads are passable. On the first day, April 29, we will try to get to stops 1–5, the more distal parts of the Ogallala and younger deposits in Nebraska. On April 30, we will try to visit stops 6–9. Stops 10–15, in areas closer to the sediment sources of the Ogallala and some of the younger units, will be …


Geologic Map Of Morrill County, Nebraska, James B. Swinehart, Robert F. Diffendal Jr. Jan 1995

Geologic Map Of Morrill County, Nebraska, James B. Swinehart, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Morrill County, Nebraska, is perhaps the most geologically interesting county in the panhandle of Nebraska. Surficial deposits of alluvium, colluvium, loess, and eolian sand of Quaternary age cover large parts of the county. Holocene and latest Pleistocene(?) eolian sand as much as 150 It thick covers much of the area north of North Platte Valley and mantles Quaternary alluvial deposits to the south. A thin veneer of loess overlies bedrock in the uplands of the southern part of the county. Alluvium underlies the valley floors and caps river and stream terraces. Two units of older Quaternary alluvium are exposed in …


Environments Of Aeolian Deposition In South-Central Nebraska During The Last Glacial Maximum, Zhao-Dong Feng, William C. Johnson, Robert F. Diffendal Jr. Jan 1994

Environments Of Aeolian Deposition In South-Central Nebraska During The Last Glacial Maximum, Zhao-Dong Feng, William C. Johnson, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The Peoria loess of south-central Nebraska, deposited approximately during the last Glacial Maximum, can be subdivided into three zones: an upper laminated loess and a lower massive loess, separated by a dark gley zone in which bison bones and spruce charcoal are found. The lower Peoria unit is characterized by high organic matter content, relatively high bulk density, and common root channels. The upper Peoria unit has rhythmic patterns of two orders: strongly gleyed and weakly gleyed zones alternating in couplets about 2-5 m thick, and coarse- and fine-grained laminae of second order, about 2-4 mm thick. The strongly gleyed …


Geomorphic And Structural Features Of The Alliance 1º × 2º Quadrangle, Western Nebraska, Discernible From Synthetic-Aperture Radar Imagery And Digital Shaded-Relief Maps, Robert F. Diffendal Jr. Jan 1994

Geomorphic And Structural Features Of The Alliance 1º × 2º Quadrangle, Western Nebraska, Discernible From Synthetic-Aperture Radar Imagery And Digital Shaded-Relief Maps, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The digital shaded-relief map of the United States and the synthetic-aperture radar map of the Alliance Nebraska 1º x 2º area prepared by the U.S. Geological Survey (USGS) in the former case and for the USGS in the latter show oriented landforms and lineaments in northwest Nebraska. Parallel and subparallel hills and valleys developed on different geologic materials ranging from shales through sandstones to loess and eolian sand appear to be wind erosional features subsequently modified by running water. The long axes of these hills and valleys generally trend between N40"W and N50"W. Similar features also occur across major areas …


Probable Glacial Climatic Conditions In Source Areas During Deposition Of Parts Of The Ash Hollow Formation, Ogallala Group (Late Tertiary), Of Western Nebraska, Patricia E. Helland, Robert F. Diffendal Jr. Oct 1993

Probable Glacial Climatic Conditions In Source Areas During Deposition Of Parts Of The Ash Hollow Formation, Ogallala Group (Late Tertiary), Of Western Nebraska, Patricia E. Helland, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Evidence of the climatic conditions in the mountain sediment source areas for the late Tertiary Ash Hollow Formation of the Ogallala Group in western Nebraska has been sought in an SEM (scanning electron microscope) study of surface features on detrital quartz grains from these deposits. The following lines of indirect evidence raised the possibility of glacial conditions: uplift of up to 3500 m in the source areas, paleohydrologic parameters indicative of a transport system analogous to the modern North Saskatchewan River, and possible cold climate surface features on cobbles from the deposits. SEM analysis shows that five of the nine …


Understanding Groundwater Starts With The Rocks: Geologic Fralnework, Groundwater Occurrence And Irrigation Development In Nebraska, Robert F. Diffendal Jr. Mar 1993

Understanding Groundwater Starts With The Rocks: Geologic Fralnework, Groundwater Occurrence And Irrigation Development In Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Nebraska is blessed with abundant groundwater. This groundwater is found beneath much of the state, principally in the sediments and sedimentary rocks that blanket the ancient and largely crystalline rocks geologists call Precambrian (see block diagram of Nebraska's geology, p. 50). These younger deposits contain pieces of evidence such as fossils and sedimentary features that reveal the tremendous changes in the environment that have gone on over the last 570 million years, during which these deposits accumulated. Change is the name of the game in geologic history, just as it is in human history. Fundamental changes in geologic history across …


Profiles: Nelson Horatio Darton: His Surveys Laid The Foundation, Robert F. Diffendal Jr. Mar 1993

Profiles: Nelson Horatio Darton: His Surveys Laid The Foundation, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

No serious researcher studying the development of water resources in Nebraska, or for that matter in the central Great Plains, can overlook the works of Nelson Horatio Darton, the first geologist to study and publish about those resources in any detail. Darton originally published the names and characteristics of many hydrogeologic units beneath much of Nebraska, now used by groups as diverse as scientists, well drillers and the general public. These works are listed below. As an indication of the value of these early efforts, I have used these works for my research and can testify to their accuracy and …


Application Of Sealevel Stratigraphy To Neogene Great Plains Stratigraphy, Robert F. Diffendal Jr., A. Lowrie Jan 1993

Application Of Sealevel Stratigraphy To Neogene Great Plains Stratigraphy, Robert F. Diffendal Jr., A. Lowrie

Robert F. Diffendal, Jr., Publications

Absolute-dated high frequency (Milankovitch cycles) marine climate/sealevel oscillatory stratigraphy can be correlated generally with continental stratigraphies. Improvements in absolute dating of Neogene formations across the North American Great Plains make this a candidate area in which to correlate marine and continental stratigraphies. Mid-latitude continental areas respond directly to climate variations. During glaciated/ cold climates, sealevel lowering results in steepened river gradients, increased erosion all along the river channel, and larger stress-bed loads. This, combined with glacial catastrophic flooding, produces greater cut-and-fill sequences along river systems than crevasse splays along the emergent coastal plain, deltas along the shelf, and submarine fans …


Stable Isotope Composition Of Calcareous Paleosols And Ground-Water Cements From The Ogallala Group (Neogene), Western Nebraska, Leonard Robert Gardner, Robert F. Diffendal Jr., Douglas F. Williams May 1992

Stable Isotope Composition Of Calcareous Paleosols And Ground-Water Cements From The Ogallala Group (Neogene), Western Nebraska, Leonard Robert Gardner, Robert F. Diffendal Jr., Douglas F. Williams

Robert F. Diffendal, Jr., Publications

A preliminary survey has been made of the stable isotope composition of secondary carbonates in the Ogallala Group of western Nebraska. The purpose of the study was to ascertain whether the isotopic signatures of calcareous paleosols in the fine grained facies of the Ogallala and groundwater cements in gravel facies might provide a basis for stratigraphic correlation and/or paleoclimatic interpretation.

The groundwater cemented channel gravels are modestly depicted in IRO (δ18O = –10‰) as compared to calcareous paleo'sols (δ18O = –8.0 to –9.0‰). Gravels of different age, however, have essentially identical isotopic signatures. The isotopic variability …


Geologic Map Showing Configuration Of The Bedrock Surface, North Platte, 1 ° X 2 ° Quadrangle, Nebraska, Robert F. Diffendal Jr. Jan 1991

Geologic Map Showing Configuration Of The Bedrock Surface, North Platte, 1 ° X 2 ° Quadrangle, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The map area, in west-central Nebraska, is largely covered by surficial deposits of eolian sand, loess, and alluvium ranging in age from Holocene to Pliocene. Holocene and late Pleistocene(?) eolian sand, as much as 300 ft (91 m) thick, covers most of the area north of the North Platte and Platte Rivers, and also covers a small area south of those rivers. The Peoria Loess of Quaternary age overlies most of the remaining upland north of the Platte River in southwestern Logan, northeastern Lincoln, and much of western Custer and extreme northwestern Dawson Counties. Loess also mantles the divide between …


Late Pennsylvanian And Early Permian Cyclic Sedimentation, Paleogeography, Paleoecology, And Biostratigraphy In Kansas And Nebraska, Roger K. Pabian, Robert F. Diffendal, Jr. Jr. Jan 1989

Late Pennsylvanian And Early Permian Cyclic Sedimentation, Paleogeography, Paleoecology, And Biostratigraphy In Kansas And Nebraska, Roger K. Pabian, Robert F. Diffendal, Jr. Jr.

Robert F. Diffendal, Jr., Publications

Overview of Upper Pennsylvanian Cyclic Sedimentation in Kansas and Nebraska, Philip H. Heckel, Department of Geology, University of Iowa, Iowa City, Iowa

With contributions from:

Christopher G. Maples and W. Lynn Watney, Kansas Geological Survey, Lawrence, Kansas

John Harris, Shell Western Exploration and Production, Inc., Houston, Texas

David Ball, Champlin Petroleum Company, Houston, Texas

Philip H. Heckel, University of Iowa, Iowa City, Iowa

R. R. West, V. Voegeli, S. Roth, K. Leonard, H. R. Feldman, and C. Cunningham, Kansas State University, Manhattan, Kansas

Royal H. Mapes, Ohio University, Athens, Ohio

Hans-Peter Schultze, University of Kansas, Lawrence, Kansas

R. Matt Joeckel, …


Lake Maloney Quadrangle, Nebraska--Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Jan 1989

Lake Maloney Quadrangle, Nebraska--Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5 minute series (topographic)

100° 45' to 100° 52' 30"

41° 00' to 41° 07' 30"

Includes Ogallala Outcrops (pencil)


River Potholes: Modern And Ancient, Robert F. Diffendal Jr. Oct 1988

River Potholes: Modern And Ancient, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

A river pothole is a cylindrical, bowl-shaped, or irregular hollow that is usually deeper than wide. It is formed in the rocky bed of a stream by either the grinding action of sediment whirled around by stream eddies or the force of fast flowing water. Potholes usually have spirally grooved surfaces. Their widths and depths range from a few inches to many feet. Potholes on the floor of the Susquehanna River near Columbia, Pennsylvania, for example, are large enough to hold objects the size of a small car.

Potholes generally are formed in fairly homogeneous rock by streams that at …


Singleton Ranch Quadrangle, Nebraska—Banner, Kimball, And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Jun 1988

Singleton Ranch Quadrangle, Nebraska—Banner, Kimball, And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Singleton Ranch Quadrangle, Nebraska—Banner, Kimball, and Cheyenne Counties

7.5 minute series (topographic), scale 1:24000

103°22'30" to 103°30'

41°22'30" to 41°30'

Toa, Ql, Qalc

June 13, 1988


Courthouse Rock Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr. Jun 1988

Courthouse Rock 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° 30' — 41° 37'30"

103° 00' — 103° 07'30"

Scale 1:24,000

Completed June 6, 1988

High resolution .tif file attached below as supplemental file


Redington Quadrangle, Nebraska—Banner And Morrill Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Apr 1988

Redington Quadrangle, Nebraska—Banner And Morrill Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Redington Quadrangle, Nebraska—Banner and Morrill Counties

7.5 minute series (topographic), scale 1:24000

103°15' to 103°22'30"

41°30' to 41°37'30"

Twb, Qalc, Toa, IW, Tamch, Lower Whitney, Upper Whitney

April 5, 1988


Lisco Nw Quadrangle, Nebraska—Garden, Morrill, And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Mar 1988

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

Robert F. Diffendal, Jr., Publications

Lisco NW Quadrangle, Nebraska—Garden, Morrill, and Cheyenne Counties

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

102°37'30" to 102°45'

41°22'30" to 41°30'

March 31, 1988


Fairchild Ranch Quadrangle, Morrill And Cheyenne Counties, Nebraska, Robert F. Diffendal Jr. Mar 1988

Fairchild Ranch Quadrangle, Morrill And Cheyenne 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° 22'30" — 41° 30'

102° 45' — 102° 52'30"

Scale 1:24,000

Completed March 29, 1988

High resolution .tif file attached below as supplemental file


Dalton Quadrangle, Morrill And Cheyenne Counties, Nebraska, Robert F. Diffendal Jr. Mar 1988

Dalton Quadrangle, Morrill And Cheyenne 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° 22'30" — 41° 30'

102° 52'30" — 103° 00'

Scale 1:24,000

Completed March 28, 1988

High resolution .tif file attached below as supplemental file


Mud Springs Quadrangle, Nebraska—Morrill And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Mar 1988

Mud Springs Quadrangle, Nebraska—Morrill And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Mud Springs Quadrangle, Nebraska—Morrill and Cheyenne Counties

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

103° to 103°07'30"

41°22'30" to 41°30'

Toa (Coarse sand and cobble gravel)

March 25, 1988


Horsehead Ranch Quadrangle, Morrill And Cheyenne Counties, Nebraska, Robert F. Diffendal Jr. Mar 1988

Horsehead Ranch Quadrangle, Morrill And Cheyenne 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° 22'30" — 41° 30'

103° 7'30" — 103° 15'

Scale 1:24,000

Completed March 24, 1988

High resolution .tif file attached below as supplemental file


Lawrence Fork / Potter 2 Ne Quadrangle, Nebraska—Banner, Morril, And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr. Mar 1988

Lawrence Fork / Potter 2 Ne Quadrangle, Nebraska—Banner, Morril, And Cheyenne Counties, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Lawrence Fork / Potter 2 NE Quadrangle, Nebraska—Banner, Morril, and Cheyenne Counties

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

103°15' to 103°22'30"

41°22'30" to 41°30'

Toa, Twb, Qalc, IW

March 1988


Broadwater [Se] Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr. Jan 1988

Broadwater [Se] 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° 30' — 41° 37'30"

102° 45' — 102° 52'30"

Scale 1:24,000

Completed [n.d.]

High resolution .tif file attached below as supplemental file


Broadwater Sw Quadrangle, Morrill County, Nebraska, Robert F. Diffendal Jr. Jan 1988

Broadwater Sw 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° 30' — 41° 37'30"

102° 52'30" — 103° 00'

Scale 1:24,000

Completed April 12, 1988

High resolution .tif file attached below as supplemental file


Duer Ranch, Morrill County, Nebraska: Contrast Between Cenozoic Fluvial And Eolian Deposition, James B. Swinehart, R. F. Diffendal Jr. Jan 1987

Duer Ranch, Morrill County, Nebraska: Contrast Between Cenozoic Fluvial And Eolian Deposition, James B. Swinehart, R. F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

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 rocks of Nebraska. It offers a unique area in which to examine the geometries and alluvial fills of several Miocene and Pliocene age paleovalleys and paleo-gullies. 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. In addition, Quaternary ephemeral stream development and deposits can be studied.

Location and Accessibility

Significance of the Locality

Locality Information

Measured Sections [I-IV] …


Paleohydrology Of Some Ogallala (Neogene) Streams In The Southern Panhandle Of Nebraska, R. G. Goodwin, Robert F. Diffendal Jr. Jan 1987

Paleohydrology Of Some Ogallala (Neogene) Streams In The Southern Panhandle Of Nebraska, R. G. Goodwin, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Stratification and estimated paleoflow conditions for valley-fill deposits suggest that Ogallala Group streams in western Nebraska were similar to modern streams of south-central Alberta.

Ogallala stratification includes medium-scale (0.5 to 2.0 m thick) trough crossbedded sand and gravel, tabular indistinctly horizontally bedded and imbricated gravel, and horizontally bedded sand and pebbly sand. Valley fills are 15 to 55 m thick and 800 to 1800 m wide at the top. Some are in bedrock-floored channels resembling the “inner channels” of Shepherd and Schumm (1974).

Gradients for three well exposed paleovalley floors range from 0.0014 to 0.0020 (m/m) after tectonic correction. This …


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.