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Full-Text Articles in Earth Sciences

Jurassic Eolian Oolite On A Paleohigh In The Sundance Sea, Bighorn Basin, Wyoming, Zoran Kilibarda, David Loope Aug 2015

Jurassic Eolian Oolite On A Paleohigh In The Sundance Sea, Bighorn Basin, Wyoming, Zoran Kilibarda, David Loope

David B. Loope

Aeolian limestones are widespread in the Quaternary record and have been identified in outcrops and cores of late Palaeozoic strata. These rocks have been interpreted as a low latitude signal of glacio-eustatic sea level fluctuations and have not been previously reported from the Mesozoic or from other episodes of earth history generally believed to have been non-glacial. Numerous lenticular bodies of cross-stratified oolite lie near the contact between the lower and upper members of the mudstone-dominated lower Sundance Formation (Middle and Upper Jurassic) in the Bighorn Basin of north-central Wyoming, USA. The lenses, up to 12 m thick, contain sedimentary …


Stratigraphy And Tectonics Of The Pulur (Bayburt) Region In The Eastern Pontides, Aral I. Okay, Ömer Şahi̇ntürk, Hüseyin Yakar Dec 1997

Stratigraphy And Tectonics Of The Pulur (Bayburt) Region In The Eastern Pontides, Aral I. Okay, Ömer Şahi̇ntürk, Hüseyin Yakar

Bulletin of the Mineral Research and Exploration

No abstract provided.


Stratigraphy Of The Tectonostratigraphic Units Around Hadim-Bozkir-Taşkent Region (Northern Part Of The Central Taurides, Turkey), Necdet Özgül Dec 1997

Stratigraphy Of The Tectonostratigraphic Units Around Hadim-Bozkir-Taşkent Region (Northern Part Of The Central Taurides, Turkey), Necdet Özgül

Bulletin of the Mineral Research and Exploration

No abstract provided.


Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, Sue Olafsen Lackey, Robert F. Diffendal Jr., Raymond R. Burchett, Duane A. Eversoll, Rodney J. Tremblay Sep 1997

Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, Sue Olafsen Lackey, Robert F. Diffendal Jr., Raymond R. Burchett, Duane A. Eversoll, Rodney J. Tremblay

Conservation and Survey Division

Field trip guide, for the Nebraska Well Drillers Association, covering northeastern Nebraska geology from September 1997.


Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr. Sep 1997

Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The geology of the study area has been investigated many times over more than a century. Interested readers are directed to the report by Diffendal and Voorhies (1994), which gives a more detailed overview of the results of the investigations and lists most of the more important reports about the area’s geology.

The names of the sedimentary rock strata and unlithified sediments exposed in and underlying all or parts of the study area are shown in Table V.I. These formations range in age from more than 85 million years to sediments being deposited today by winds, water, and downslope movements …


Geology Of Niobrara State Park, Knox County, Nebraska, And Adjacent Areas, With A Brief History Of The Park, Gavins Point Dam, And Lewis And Clark Lake, Charles A. Flowerday, Robert F. Diffendal Jr., R. L. Skelly, F. G. Ethridge, D. A. Eversoll, David K. Watkins, B. E. Bailey Sep 1997

Geology Of Niobrara State Park, Knox County, Nebraska, And Adjacent Areas, With A Brief History Of The Park, Gavins Point Dam, And Lewis And Clark Lake, Charles A. Flowerday, Robert F. Diffendal Jr., R. L. Skelly, F. G. Ethridge, D. A. Eversoll, David K. Watkins, B. E. Bailey

Conservation and Survey Division

Location

Niobrara State Park is located in northwestern Knox County, Nebraska, just west of the town of Niobrara and on the west side of the Niobrara River. The present park was opened in the summer of 1987. Mostly north of Nebraska Highway 12, the site is hilly with bluffs overlooking the Missouri and Niobrara rivers. Excellent facilities include paved roads, cabins, an outdoor swimming pooi, hiking trails, picnic and camping sites, horseback riding trails, playgrounds, restrooms, a group lodge, and an interpretive shelter. Many vantage points in the park have beautiful views of the lower Niobrara Valley and the middle …


Geochemical Characteristics And Correlations Within The Triassic-Jurassic Age Gabbs And Sunrise Formations Of West Central Nevada, Karen Elizabeth Boelling May 1997

Geochemical Characteristics And Correlations Within The Triassic-Jurassic Age Gabbs And Sunrise Formations Of West Central Nevada, Karen Elizabeth Boelling

Dissertations and Theses

Trace and minor element geochemistry was determined using Instrumental Neutron Activation Analysis for ninety-six (96) limestone and calcareous siltstone samples from four stratigraphic sections in the Triassic-Jurassic age Gabbs and Sunrise formations of west central Nevada. Geochemical data support lithologic and faunal interpretations of relative basin positions of the Sunrise Formation stratigraphic sections, as well as basin development (including transgressive­-regressive sequences) during deposition of the Gabbs and Sunrise formations at New York Canyon (Gabbs Valley Range). All sections show characteristics of both oceanic and continental island arc sources. Rare positive Eu anomalies relative to chondrites suggest that the Gabbs Formation …


Middle Shoreface Intervals: Evidence Of Barred Nearshore Systems In He Stratigraphic Record, James V. Gravette Apr 1997

Middle Shoreface Intervals: Evidence Of Barred Nearshore Systems In He Stratigraphic Record, James V. Gravette

OES Theses and Dissertations

An interpretation for middle shoreface (MSF) intervals was developed by comparing MSF intervals from the Upper Cretaceous (Campanian) Blackhawk Formation, east-central Utah, with conceptual models proposed for modern nearshore areas. Specifically, MSF intervals identified within the Sunnyside Member were compared with MSF intervals identified within the Spring Canyon (Kamola and Van Wagoner, 1995) and the Aberdeen (Kamola, unpublished data) members.

A comparison of MSF interval data revealed that MSF intervals occur stratigraphically between upper and lower shore face deposits, disrupting the standard vertical succession for nearshore marine deposits (consisting of offshore, lower shore face, upper shore face, and foreshore deposits). …


Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen Apr 1997

Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen

OES Theses and Dissertations

Four molluscan assemblage zones in southern Florida corresponding to the Pinecrest Sand Member of the Tamiami Formation, and the Caloosahatchee, Bermont and Fort Thompson shell beds were identified following quantitative and qualitative analyses of the fossil molluscan fauna. Twenty-eight bulk sediment samples collected from 16 localities across southern Florida were processed for fossil material, and yielded nearly 60,000 specimens belonging to 311 species. A Q-mode cluster analysis compared sediment samples on the basis of 188 species whose abundances had been converted to binary presence-absence form. The cluster analysis was run four times using the Jaccard and Dice similarity coefficients as …


Pre-Thrust Normal Faults And Post-Tectonic Micas In The Taconic Range Of West-Central Vermont, Nicholas W. Hayman Jan 1997

Pre-Thrust Normal Faults And Post-Tectonic Micas In The Taconic Range Of West-Central Vermont, Nicholas W. Hayman

Geology Theses and Dissertations

New geologic maps show that the Champlain Thrust System traces continuously between Shoreham and Benson, Vermont. The Champlain Thrust System consists of at least three internally imbricated thrust slices in continental shelf facies quartzites and carbonates. From north to south there is a structurally controlled thinning of the Champlain Thrust System, and a climbing in stratigraphic level by the thrusts. Within the Champlain Thrust System are a set of across-strike structures which create offsets in the thrusts and the surrounding lithic map unit boundaries. These structures function as lateral ramps in the thrust system geometry and bound thrust duplexes. Often …


Comparison Of Source Rock Geochemistry Of Selected Rocks From The Schei Point Group And Ringnes Formation, Sverdrup Basin, Arctic Canada, P. K. Mukhopadhyay, F. Goodarzi, Michael A. Kruge, M. H. Alimi Jan 1997

Comparison Of Source Rock Geochemistry Of Selected Rocks From The Schei Point Group And Ringnes Formation, Sverdrup Basin, Arctic Canada, P. K. Mukhopadhyay, F. Goodarzi, Michael A. Kruge, M. H. Alimi

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Organic-rich from the Schei Point group (middle to late Triassic in age) and the Ringnes formation (late Jurassic) from the Sverdrup basin of the Canadian arctic archipelago have been geochemically evaluated for source rock characterization. Most samples from the Schei Point group are organic-rich (> 2% TOC) and are considered as immature to mature oil-prone source rocks [kerogen types I, I-II (IIA) and II (IIA)]. These kerogen types contain abundant AOM1, AOM2 and alginite (Tasmanales, Nostocopsis, Leiosphaeridia, acritarch and dinoflagellate) with variable amounts of vitrinite, inertinite and exinite. Samples from the Ringnes formation contain dominant vitrinite and inertinite …


Grand Tour-Part 2: Petrogenesis And Thermal Evolution Of Deep Continental-Crust: The Record From The East Humboldt Range, Nevada, Allen J. Mcgrew, Mark T. Peters Jan 1997

Grand Tour-Part 2: Petrogenesis And Thermal Evolution Of Deep Continental-Crust: The Record From The East Humboldt Range, Nevada, Allen J. Mcgrew, Mark T. Peters

Geology Faculty Publications

The northern part of the East Humboldt Range, Nevada, provides a rare opportunity to explore the petrogenetic environment of deep levels in the middle crust during both large-scale Mesozoic contraction and Cenozoic regional extension. On this segment of the field trip, we will explore evidence bearing on the character of the metamorphic and magmatic history of this terrane, and attempt to link these constraints to the rheology and tectonic evolution of the middle crust during the Mesozoic and Cenozoic.


The Grand Tour Of The Ruby-East Humboldt Metamorphic Core Complex, Northeastern Nevada: Part 1-Introduction & Road Log, Arthur W. Snoke, Keith A. Howard, Allen J. Mcgrew, Bradford R. Burton, Calvin G. Barnes, Mark T. Peters, James E. Wright Jan 1997

The Grand Tour Of The Ruby-East Humboldt Metamorphic Core Complex, Northeastern Nevada: Part 1-Introduction & Road Log, Arthur W. Snoke, Keith A. Howard, Allen J. Mcgrew, Bradford R. Burton, Calvin G. Barnes, Mark T. Peters, James E. Wright

Geology Faculty Publications

The purpose of this geological excursion is to provide an overview of the multiphase developmental history of the Ruby Mountains and East Humboldt Range, northeastern Nevada. Although these mountain ranges are commonly cited as a classic example of a Cordilleran metamorphic core complex developed through large-magnitude, mid-Tertiary crustal extension, a preceding polyphase Mesozoic contractional history is also well preserved in the ranges. An early phase of this history involved Late Jurassic two-mica granitic magmatism, high-temperature but relatively low-pressure metamorphism, and polyphase deformation in the central Ruby Mountains. In the northern Ruby Mountains and East Humboldt Range, a Late Cretaceous history …


Composite Section Of Cretaceous Rocks In Nebraska, R. R. Burchett Jan 1997

Composite Section Of Cretaceous Rocks In Nebraska, R. R. Burchett

Conservation and Survey Division

No abstract provided.


So You Need A Water Well? A Consumer's Guide To Homeowners' Drinking Water, Charles A. Flowerday, Vincent H. Dreeszen Jan 1997

So You Need A Water Well? A Consumer's Guide To Homeowners' Drinking Water, Charles A. Flowerday, Vincent H. Dreeszen

Conservation and Survey Division

No abstract provided.


Composite Section Of Cretaceous Rocks In Nebraska, R.R. Burchett Jan 1997

Composite Section Of Cretaceous Rocks In Nebraska, R.R. Burchett

Conservation and Survey Division

No abstract provided.


Discovery Of Fossil Cretaceous Bird In Southwest Arkansas, Leo Carson Davis, Kathie Harris Jan 1997

Discovery Of Fossil Cretaceous Bird In Southwest Arkansas, Leo Carson Davis, Kathie Harris

Journal of the Arkansas Academy of Science

No abstract provided.


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 …


Sem Analysis Of Quartz Sand Grain Surface Textures Indicates Alluvial/Colluvial Origin Of The Quaternary "Glacial" Boulder Clays At Huangshan (Yellow Mountain), East-Central China, P. E. Helland, Pei-Hua Huang, Robert F. Diffendal Jr. Jan 1997

Sem Analysis Of Quartz Sand Grain Surface Textures Indicates Alluvial/Colluvial Origin Of The Quaternary "Glacial" Boulder Clays At Huangshan (Yellow Mountain), East-Central China, P. E. Helland, Pei-Hua Huang, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Geomorphic features and Pleistocene deposits on Huangshan have been attributed to glaciation. Recent reassessment questions this interpretation. As part of the reassessment, quartz sand grains from deposits identified as glacial boulder clays (till composed of boulders in a clay or silt matrix) were analyzed by scanning electron microscope for evidence of their sedimentary history. Surface textures found on the boulder-clay grains were compared with those on grains with known sedimentary histories including glacial, grus, colluvial, and alluvial grains. The analysis shows that the grains lack typical glacial textures. The surface textures present indicate a complex history. Non-uniformly weathered grain surfaces …


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 …


Explanation Of Geologic Map Units For Use With University Of Nebraska-Lincoln Conservation And Survey Division Open-File Maps Nos. 53-65., Hannan E. Lagarry, Leigh Anne Lagarry Jan 1997

Explanation Of Geologic Map Units For Use With University Of Nebraska-Lincoln Conservation And Survey Division Open-File Maps Nos. 53-65., Hannan E. Lagarry, Leigh Anne Lagarry

Conservation and Survey Division

No abstract provided.


Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, S. Olafsen Lackey, Robert F. Diffendal Jr., R. R. Burchett, D. A. Eversoll, R. A. Tremblay Jan 1997

Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, S. Olafsen Lackey, Robert F. Diffendal Jr., R. R. Burchett, D. A. Eversoll, R. A. Tremblay

Conservation and Survey Division

Field trip guide for the Nebraska Well Drillers Association covering northeastern Nebraska geology from 1997.


Field Trip Guide ( For The Nebraska Well Drillers Association) Western Nebraska Geology, S. Sibray, D. Heinen, D. Eversoll, R. Tremblay, J. Cannia, J. Belieu Jan 1997

Field Trip Guide ( For The Nebraska Well Drillers Association) Western Nebraska Geology, S. Sibray, D. Heinen, D. Eversoll, R. Tremblay, J. Cannia, J. Belieu

Conservation and Survey Division

No abstract provided.


Fillmore County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside Jan 1997

Fillmore County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside

Conservation and Survey Division

No abstract provided.


Resource Notes-Academic Year 1996-97 Jan 1997

Resource Notes-Academic Year 1996-97

Conservation and Survey Division

No abstract provided.


Resource News-Summer 1997 Jan 1997

Resource News-Summer 1997

Conservation and Survey Division

No abstract provided.


Franklin County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside Jan 1997

Franklin County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside

Conservation and Survey Division

No abstract provided.


The Effects Of Plains Pocket Gophers On Two Varieties Of Alfalfa, Debra S. Baker Jan 1997

The Effects Of Plains Pocket Gophers On Two Varieties Of Alfalfa, Debra S. Baker

Conservation and Survey Division

No abstract provided.


Resource News-Spring 1997 Jan 1997

Resource News-Spring 1997

Conservation and Survey Division

No abstract provided.


Geology Of The Montrose, Orella, Wolf Butte, Roundtop And Horn 7.5' Usgs Quadrangles, Sioux And Dawes Counties, Nebraska, Hannan E. Lagarry, Leigh Anne Lagarry Jan 1997

Geology Of The Montrose, Orella, Wolf Butte, Roundtop And Horn 7.5' Usgs Quadrangles, Sioux And Dawes Counties, Nebraska, Hannan E. Lagarry, Leigh Anne Lagarry

Conservation and Survey Division

No abstract provided.