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Structural Geology Of The Northeast Quarter Of The Dutchman Butte Quadrangle, Southwest Oregon, Rauno K. Perttu Apr 1976

Structural Geology Of The Northeast Quarter Of The Dutchman Butte Quadrangle, Southwest Oregon, Rauno K. Perttu

Dissertations and Theses

The northeast quarter of the Dutchman Butte quadrangle straddles the boundary of the Mesozoic Klamath Mountains province and the Tertiary Coast Range province. The boundary in this area is controlled by a major easttrending fault zone, herein named the Canyonville fault zone. Jurassic Rogue, Dothan, and Otter Point Formations have been offset right-laterally at least 40 kilometers. In latest Jurassic and early Cretaceous time, the fault zone formed the shoreline along which sediments of the Myrtle Group were deposited.

Movement on the Canyonville fault zone becale down-to-the-north in Eocene time forming the southern margin of the Eocene Coast Range basin. …


Geology Newsletter- 1976, Department Of Geology Apr 1976

Geology Newsletter- 1976, Department Of Geology

Geological and Environmental Sciences News

Vol. 1, No . 2

  • Dear Department Alumni and Friends
  • Graduate Students
  • Geology Earth Science Club News
  • This N' That


Geology And Ore Deposits Of The Johnnie District, Nye County, Nevada, Stanley Wayne Ivosevic Mar 1976

Geology And Ore Deposits Of The Johnnie District, Nye County, Nevada, Stanley Wayne Ivosevic

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Johnnie district, in the northwestern Spring Mountains, Nye County, Nevada, may have produced a little under 100,000 troy oz of gold, since the discovery of the district in 1890.

An approximately 13,000-ft-thick (4,000 m) section of east-dipping upper Precambrian through Middle Cambrian miogeosynclinal clastic and carbonate rocks is exposed in the district. The strata are, in order of decreasing age, the Johnnie Formation, Stirling Quartzite, Wood Canyon Formation, Zabriskie Quartzite, and Carrara and Bonanza King Formations. These are overlain by Cenozoic units which include and older unit and a younger unit of fanglomerate, the older containing a megabreccia deposit, …


Geology Of The Breitenbush Hot Springs Area, Cascade Range, Oregon, Clifford Michael Clayton Feb 1976

Geology Of The Breitenbush Hot Springs Area, Cascade Range, Oregon, Clifford Michael Clayton

Dissertations and Theses

The Breitenbush Hot Springs area lies on the boundary of folded middle to late Tertiary Western Cascade rocks and younger High Cascade rocks. Within the mapped area the Western Cascade rocks are represented by four formations. The Detroit Beds, a sequence of interstratified tuffaceous sandstone, mudflow breccia, and tuff, is overlain unconformably by the Breitenbush Tuff. The Breitenbush Tuff consists of three units of welded pumice-rich crystal-vitric ash-flow tuffs interbedded with tuffaceous sedimentary rocks. The Outerson Formation unconformably overlies the Breitenbush Tuff and consists primarily of basaltic lava and breccia.

The Outerson Formation includes three localized members: a basal, glassy, …


Water Resources Of Pierce County, Nebraska, Robert E. Brogden, Richard A. Engberg Feb 1976

Water Resources Of Pierce County, Nebraska, Robert E. Brogden, Richard A. Engberg

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Regional Tectonics And Seismicity Of Eastern Nebraska, Annual Report June 1, 1976- June 1, 1977, R. R. Burchett Jan 1976

Regional Tectonics And Seismicity Of Eastern Nebraska, Annual Report June 1, 1976- June 1, 1977, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


A Revision Of The Genus Strategus (Coleoptera: Scarabaeidae), Brett C. Ratcliffe Jan 1976

A Revision Of The Genus Strategus (Coleoptera: Scarabaeidae), Brett C. Ratcliffe

Bulletin of the University of Nebraska State Museum (1924–2023)

The New World genus Strategus Kirby is here defined and revised for the first time. Eight species are described as new: S. atlanticus, S. caymani, S. craigi, S. hipposiderus, S. howdeni, S. longichomperus, S. symphenax, and S. tarquinius; 12 new junior synonyms are established (including the rejection of six previously valid species)'; one species is raised from synonymy; and two new replacement names are proposed. Strategus now contains one fossil species and 31 valid extant species. A key to the males and females of all the species is provided for the first …


Petrology Of The Oceanographer Fracture Zone (35ºn35ºw), Tsugio Shibata Jan 1976

Petrology Of The Oceanographer Fracture Zone (35ºn35ºw), Tsugio Shibata

Geology Theses and Dissertations

During a geological and geophysical survey of the Oceanographer Fracture Zone (35°N, 35°W), seventeen dredge hauls containing a variety of rocks were obtained. Petrographic study shows that these rock samples can be classified into six main rock types: fresh basalt, weathered basalt, metabasalt, gabbro, metagabbro, and serpentinite. Most of the dredge hauls were positioned on the steep, southern wall of the fracture zone, and an inference from the dredging results suggests that basalt is the most abundant rock type which outcrops at the junction between the rift valley and the fracture zone; however, as we move away from the junction, …


Structural Studies In The Northern Chester Dome Of East-Central Vermont, Bruce Wallace Nesbit Jan 1976

Structural Studies In The Northern Chester Dome Of East-Central Vermont, Bruce Wallace Nesbit

Geology Theses and Dissertations

Rocks in the Eastern Vermont Sequence are highly metamorphosed and are said to range in age from Precambrian to Siluro-Devonian. The sequence outcrops on Keyes Mountain, about 6km Northwest of Felchville, Vermont, and an area on this mountain about 2km square was mapped in great detail.
The dominant rock type found is quartzofeldspathic gneiss, but schistose gneiss, amphibolite, quartzite and schist also occur. Most of these rocks are layered but layering has been transposed in many places and much of it is probably secondary. Layering and schistosity both dip dominantly to the north at about 25º.
A number of mesoscopic …


Nebraska Mineral Operations Review, 1975, Raymond R. Burchett, Duane A. Eversoll Jan 1976

Nebraska Mineral Operations Review, 1975, Raymond R. Burchett, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

During 1975, there were active in Nebraska 42 limestone quarries; 596 sand, gravel and silt or siltstone pits; 8 clay or shale pits; 22 sandstone pits; and 1 peat pit. These 669 mining operations disturbed 663 acres and restored 161 acres during the year.


1974 Nonflood-Stage Chemical Loads Of The Buffalo River, Arkansas, Kenneth F. Steele, George H. Wagner Jan 1976

1974 Nonflood-Stage Chemical Loads Of The Buffalo River, Arkansas, Kenneth F. Steele, George H. Wagner

Journal of the Arkansas Academy of Science

Dissolved Ca, Mg, Na, K, Fe, Mn, and Zn loads of the Buffalo River generally show trends along the river attributable to changes in geology and vary with the season because of concentration by evapotranspiration and dilution by rain. Suspended material element loads show neither seasonal trends nor trends along the river. The Fe load for the river is predominantly in the suspended material, the Mn load is divided approximately evenly between dissolved and suspended material, and Ca, Mg, Na, K, and Zn are predominantly in the dissolved load.


Glacial Deposits, Vol. 4, 1975-1976, Department Of Geography-Geology Jan 1976

Glacial Deposits, Vol. 4, 1975-1976, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Nebraska Groundwater Level (Decline & Rise) And Location Of Registered Wells, 1976 Jan 1976

Nebraska Groundwater Level (Decline & Rise) And Location Of Registered Wells, 1976

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Location Of Registered Irrigation Wells In Nebraska As Of 1976 Jan 1976

Location Of Registered Irrigation Wells In Nebraska As Of 1976

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Water Resources Data For Nebraska Water Year 1975 Jan 1976

Water Resources Data For Nebraska Water Year 1975

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Geology Of The Zacapa Quadrangle And Vicinity, Guatemala, Central America, David Philip Schwartz Jan 1976

Geology Of The Zacapa Quadrangle And Vicinity, Guatemala, Central America, David Philip Schwartz

Graduate Dissertations and Theses

Geologic mapping in the Zacapa quadrangle and southern Rio Hondo quadrangle has shown that the Las Ovejas Complex, of probable pre-Early Pennsylvanian age and the oldest rock south of the Motagua fault zone, is a sequence of interlayered schist, marble, amphibolite, gneiss and associated penetratively deformed diorite, tonalite and granodiorite. Metavolcanic, metavolcaniclastic, and metasedimentary rock includes original basalt, dacitic and rhyodacitic tuff, minor andesite, limestone and pelite. Emplacement of diorite coincided with regional prograde metamorphism to middle and upper amphibolite facies. Hornblende, diopside, staurolite, sillimanite, and K-feldspar formed in rock of appropriate bulk composition. In the Zacapa quadrangle, metamorphic grade …


Geology, Mineralogy, And Fluid Inclusion Geothermometry Of The El Paso Gold Mine, Cripple Creek, Colorado, Charles Albon Lane Jan 1976

Geology, Mineralogy, And Fluid Inclusion Geothermometry Of The El Paso Gold Mine, Cripple Creek, Colorado, Charles Albon Lane

Masters Theses

"The Cripple Creek district consists of a deeply- eroded, breccia-filled volcanic subsidence basin. Subsidence of the basin occurred along fissures formed by fracturing during the Laramide orogeny. The material filling the crater probably developed first as fissure flows. Erosion of the volcanics formed the material now filling the basin. Volcanic activity was accompanied by intrusion of numerous sills, dikes, and stocks of several different rock types into the breccia and surrounding granite, punctuated by occasional explosive activity. The majority of the mines in the district lie within the volcanic center; however, a few important ones, most notably the El Paso …


Areal Geology, Brecciation, And Mineralization In The Trout Creek Area, Park And Chaffee Counties, Colorado, Barry Plin Mercer Jan 1976

Areal Geology, Brecciation, And Mineralization In The Trout Creek Area, Park And Chaffee Counties, Colorado, Barry Plin Mercer

Masters Theses

"The principle purpose of this thesis research has been to map rock types in an area selected for its occurrence of lead-zinc mineralization, and particularly to examine the character and origin of breccias present in the Leadville Limestone. The thesis area is located in Colorado along the east flank of the southernmost Mosquito Range, bounded by Buffalo Peaks Volcanic field on the north and Trout Creek on the south. Units mapped include the Sawatch Quartzite (Cambrian), Manitou Limestone (lower Ordovician), Harding Sandstone (middle Ordovician), Fremont Limestone (upper Ordovician), Parting Quartzite (Devonian), Dyer Dolomite (Devonian), and Leadville Limestone (Mississippian). The Leadville …


Geology Of The Western Portion Of The Dogtooth Pluton, Lake Of The Woods Region, Southwestern Ontario, Richard H. Pilatzke Jan 1976

Geology Of The Western Portion Of The Dogtooth Pluton, Lake Of The Woods Region, Southwestern Ontario, Richard H. Pilatzke

Theses and Dissertations

A 10 km2 portion of a subsolvus, syntectonic or posttectonic grano dioritic intrusion located about 16 km east of Kenora, Ontario was extensively sampled for study by petrographic modal analysis and trend surface analysis. The Dogtooth pluton, the main intrusive body sampled, is part of a granitic batholith known as the Dryberry dome, which is interpreted to have been intruded into supracrustal volcanic and sedi mentary rocks about 2480 million years ago during the Kenoran Orogeny. The Longbow pluton, which was also sampled, occurs at the west margin of the Dryberry dome in contact with the supracrustal rocks to the …


Foraminiferids Of The Cannonball Formation (Paleocene, Danian) In Western North Dakota, William E. Fenner Jan 1976

Foraminiferids Of The Cannonball Formation (Paleocene, Danian) In Western North Dakota, William E. Fenner

Theses and Dissertations

In 1974 and 1975 about 2800 samples (of which 265 contained foraminiferids) of the Cannonball Formation were collected from 60 water test wells and two oil wells in Adams, Bowman, Burleigh, Divide, Dunn, Grant, Mercer, Morton, Oliver, Sioux, and Ward Counties in western North Dakota. Fifty species of benthonic foraminiferids and four species of planktonic foraminiferids were identified including eight textulariines, two milio lines and 44 rotaliines. Taxa reported for the first time from the Can nonball include: Reophax sp. (2 species), Ammobaculites expansus Plummer, Spiroplectammina wilcoxensis Cushman and Ponton, Quinqueloculina plummerae Cushman and Todd, Dentalina eocenica Cushman, Lenticulina alabamensis …


Pleistocene Geology Of The Comstock-Sebeka Area, West-Central Minnesota, Curtis A. Anderson Jan 1976

Pleistocene Geology Of The Comstock-Sebeka Area, West-Central Minnesota, Curtis A. Anderson

Theses and Dissertations

This study is a reconnaissance of the surficial geology and a reconstruction of the late Cenozoic history of an area in westcentral Minnesota. The study area extends eastward from the Comstock area (14 miles south of Moorhead, Minnesota) in the Red River Valley to the Sebeka area (13 miles north of Wadena, Minnesota). The area is about 27 kilometres wide and 140 kilometres long.

Surface materials include Pleistocene glacial sediment and Pleistocene and Holocene fluvial, lacustrine, eolian, and bog sediment.

Four geomorphic districts are recognized. The flat Lake-Plain District is underlain by sand, silt, and clay that was deposited as …


Geomorphology And Land Use Of A Tropical Wet-Dry Environment Santander, Columbia, Joseph Ray Dec 1975

Geomorphology And Land Use Of A Tropical Wet-Dry Environment Santander, Columbia, Joseph Ray

Masters Theses & Specialist Projects

This study deals with the Holocene environmental dynamics experienced by a seasonally wet-dry landscape of tropical Columbia. In light of a high ecological sensitivity, the study area is also analyzed as the resource of man. This is done by intensive study area reconnaissance, mapping, altimeter survey, and radiocarbon dating of fluvial landforms. Also, samples of soil, pasture, and water were collected for later study, and several interviews were completed with local residents.

The study area is a tropical lowland of northcentral Columbia at about 7 ½° north latitude. A maximum local relief about 600 m is maintained by a rather …


Affects Of Thermal Assimilation And Low Grade Metamorphism On A Xenolith Bearing Basalt Dike In Marquette, Michigan, William E. Coons Dec 1975

Affects Of Thermal Assimilation And Low Grade Metamorphism On A Xenolith Bearing Basalt Dike In Marquette, Michigan, William E. Coons

Masters Theses

No abstract provided.


Trace Fossils Of The Brassfield Formation, Lower Silurian, In South-Central Ohio And North Central Kentucky, Eugene J. Murray Dec 1975

Trace Fossils Of The Brassfield Formation, Lower Silurian, In South-Central Ohio And North Central Kentucky, Eugene J. Murray

Masters Theses

No abstract provided.


Geology And Ore Deposits Of The Blackbird District Lemhi County, Idaho, Gary Lynn Purdue Dec 1975

Geology And Ore Deposits Of The Blackbird District Lemhi County, Idaho, Gary Lynn Purdue

Earth and Planetary Sciences ETDs

This report is a supplement to the Geologic Map of the Blackbird district which forms the southeast quadrant of the 15-minute Blackbird Mountain quadrangle, located in the Salmon River Mountains in Lemhi County, east central Idaho. Ore deposits in the district were developed during the first half of the twentieth century, but mining has been hampered by low-grade ores and the small size of the mineralized zones.

Outcrops are poor in the district because of heavy soil cover and talus slopes. Precambrian sedimentary rocks are part of the Belt Supergroup and have been divided into nine units. Precambrian units mapped …


Geology Of The Datil Area, Catron County, New Mexico, David A. Lopez Dec 1975

Geology Of The Datil Area, Catron County, New Mexico, David A. Lopez

Earth and Planetary Sciences ETDs

The Datil Mountains, Catron County, New Mexico, are an uplifted fault-block located along the northwestern margin of the San Augustin Plains, a Basin and Range structural basin.

No pre-Tertiary rocks occur in the study-area. All of the volcanic rocks are probably Oligocene in age, although the base of the lowest unit may be late Eocene. The oldest rocks belong to the Spears Formation and are divided into three members: A lower unit composed of andesite breccia flows and interbedded volcaniclastic conglomerate, 700+ ft (220+m); a feldspathic volcaniclastic sandstone, 100 ft (30 m); and upper porphyritic andesite flow rock, 100 ft …


Chemical Components And Diffusion, John B. Brady Nov 1975

Chemical Components And Diffusion, John B. Brady

Geosciences: Faculty Publications

Chemical components for use in the description of a system involved in a diffusion process may be selected according to the same criteria followed in the selec­tion of components for an equilibrium system. The various possible sets of components are not independent and may be interrelated through a component transformation. Actual components are preferred over nonvariable components, since they simplify descriptions and avoid theoretically nonmeasureable quantities. Two systems involved in an interdiffusion process may always be described using components that are actual components of both systems. For example, ternary reciprocal exchange of alkalis be­ tween alkali feldspars and dioctahedral alkali …


The Mineral Industry Of Nebraska, William F. Keyes, Raymond R. Burchett Nov 1975

The Mineral Industry Of Nebraska, William F. Keyes, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Reference Frames And Diffusion Coefficients, John B. Brady Oct 1975

Reference Frames And Diffusion Coefficients, John B. Brady

Geosciences: Faculty Publications

No abstract provided.


Belmar Quadrangle, Keith County, Nebraska, Robert F. Diffendal Jr. Aug 1975

Belmar 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° 52'30" — 102° 00'

Scale 1:24,000

Completed August 14, 1975

High resolution .tif file attached below as supplemental file