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Articles 27571 - 27600 of 29717

Full-Text Articles in Physical Sciences and Mathematics

Geology And Groundwater Supplies Of Box Butte County, Nebraska, 1979, V. L. Souders, F. A. Smith, J. B. Swinehart Jan 1980

Geology And Groundwater Supplies Of Box Butte County, Nebraska, 1979, V. L. Souders, F. A. Smith, J. B. Swinehart

Conservation and Survey Division

No abstract provided.


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

Ash Hollow Historical Park, Robert F. Diffendal Jr.

Conservation and Survey Division

About Ash Hollow Historical Park in Nebraska (United States).


Collecting In Nebraska's Cretaceous Strata, H. M. Degraw, R. K. Pabian Jan 1980

Collecting In Nebraska's Cretaceous Strata, H. M. Degraw, R. K. Pabian

Conservation and Survey Division

No abstract provided.


Collecting In Nebraska's Glacial Deposit, John Boellstorff Jan 1980

Collecting In Nebraska's Glacial Deposit, John Boellstorff

Conservation and Survey Division

No abstract provided.


Collecting In Western Nebraska's Cenozoic Strata, J. B. Swinehart Jan 1980

Collecting In Western Nebraska's Cenozoic Strata, J. B. Swinehart

Conservation and Survey Division

No abstract provided.


Geology Along The Republican River Valley Near Red Cloud, Nebraska, R. K. Pabian, J. B. Swinehart Jan 1980

Geology Along The Republican River Valley Near Red Cloud, Nebraska, R. K. Pabian, J. B. Swinehart

Conservation and Survey Division

No abstract provided.


The Process And Criteria For Siting Of Hazardous Waste Disposal Facilities In Nebraska, Conservation And Survey Division Jan 1980

The Process And Criteria For Siting Of Hazardous Waste Disposal Facilities In Nebraska, Conservation And Survey Division

Conservation and Survey Division

No abstract provided.


Nebraska Groundwater Level (Decline & Rise) And Location Of Registered Wells, 1980 Jan 1980

Nebraska Groundwater Level (Decline & Rise) And Location Of Registered Wells, 1980

Conservation and Survey Division

No abstract provided.


Nebraska County Map Jan 1980

Nebraska County Map

Conservation and Survey Division

No abstract provided.


Groundwater Levels In Nebraska, 1979, Martin S. Johnson, Darryll T. Pederson Jan 1980

Groundwater Levels In Nebraska, 1979, Martin S. Johnson, Darryll T. Pederson

Conservation and Survey Division

No abstract provided.


Annual Departures From Average Annual Precipitation In Nebraska, 1850-1979, Conservation Survey Division Jan 1980

Annual Departures From Average Annual Precipitation In Nebraska, 1850-1979, Conservation Survey Division

Conservation and Survey Division

No abstract provided.


Stratigraphy, Lithology, And Depositional Environment Of The Black Prince Formation Southeastern Arizona And Southwestern New Mexico, Patrick Kevin Spencer Jan 1980

Stratigraphy, Lithology, And Depositional Environment Of The Black Prince Formation Southeastern Arizona And Southwestern New Mexico, Patrick Kevin Spencer

WWU Graduate School Collection

The Black Prince Formation (new manuscript name) of southeastern Arizona and southwestern New Mexico is subdivided into four lithologic facies representing four environments of deposition. The first lithofacies consists of the basal member of the type section of the Black Prince Limestone and is a result of erosion and reworking of the underlying Escabrosa Limestone. The three limestone lithofacies suggest deposition on a shallow shelf under supratidal, intertidal and subtidal conditions. Cyclic fluctuations in sea level are seen in the rock record in the vertical alternation of lithofacies. Six unconformities are recognized and these are traceable throughout the region.

The …


Geology And Petrology Of The Lake Ann Stock And Associated Rocks, Eric William James Jan 1980

Geology And Petrology Of The Lake Ann Stock And Associated Rocks, Eric William James

WWU Graduate School Collection

The Lake Ann stock is a two pyroxene quartz monzodiorite to granodiorite epizonal intrusive emplaced into the Shuksan thrust fault in the latest Pliocene. It is similar to other Late Tertiary Cascade intrusives in mineralogy, texture, chemistry, and setting. These similarities are attributable to near surface emplacement, quick cooling and magmatic arc setting. Epizonal emplacement is indicated by fine, equigranular textures, granophyre, late stage alteration, late miarolitic dikes, plagioclase resorbed by alkali feldspar, and low pressure contact metamorphic assemblages. Temperature of emplacement was between 600°C and 925°C; pressure was less than 2 kb. Chemistry of individual samples and variation diagrams …


The Shuksan Metamorphic Suite And Shuksan Thrust Mt Watson Area, North Cascades, Washington, Ralph Albert Haugerud Jan 1980

The Shuksan Metamorphic Suite And Shuksan Thrust Mt Watson Area, North Cascades, Washington, Ralph Albert Haugerud

WWU Graduate School Collection

Rocks of the Shuksan Metamorphic Suite exposed on Mt Watson are metamorphosed pillow basalts, basaltic flows (?), basaltic tuffs, carbonaceous sediments, Mn-enriched cherty sediments, rare calcareous sediments and rare ferromanganese nodules.

Greenschist of the Suite records the following history: 1) early static hydrothermal metamorphism; 2) Early Cretaceous (about 125 ma ago) synkinematic blueschist-facies metamorphism at P~7 kb, T~350° C, Pfluid near Ptotal, XCO2 < 0.1, with production of S1 and L1 ; 3) late-metamorphic isoclinal folding (F2) around axes commonly at high angles to L1; 4) L3 crenulation of S1. Phyllite of the …


Tectonic Rotations In The Cascade Mountains Of Southern Washington, Roger G. (Roger Glenn) Bates Jan 1980

Tectonic Rotations In The Cascade Mountains Of Southern Washington, Roger G. (Roger Glenn) Bates

WWU Graduate School Collection

Paleomagnetic directions from 34 widely distributed sampling sites in the Oligocene Ohanapecosh Formation in the Cascade Mountains of southern Washington are well grouped with a mean and confidence interval of: Dec. = 27°, Inc. = 64°, α95 = 4°. When compared to the expected direction, computed from the Oligocene reference pole for stable North America, a clockwise rotation of 31° ± 12° is apparently present. This result is not significantly different from other studies within the Cascades and Coast Range of southern Washington and suggests that the two Ranges have rotated as a single unit during late Eocene to …


The Petrology, Petrography, And Geochemistry Of The Black Jack Breccia Pipe, Silver Star Plutonic Complex, Skamania County, Washington, Robert H. Birk Jan 1980

The Petrology, Petrography, And Geochemistry Of The Black Jack Breccia Pipe, Silver Star Plutonic Complex, Skamania County, Washington, Robert H. Birk

WWU Graduate School Collection

Tourmaline-bearing breccia pipes are associated with late stage Tertiary porphyritic intrusive rocks in the Silver Star Plutonic Complex.

Whole-rock geochemical analysis of rocks from the complex show a silica vs. alumina/(K2O + Na2O + CaO) trend (Feiss, 1978) toward geochemical conditions favorable for porphyry copper-type mineralization. Copper present in diorite, quartz diorite, and quartz diorite porphyry rocks probably entered silicates, whereas copper formed porphyry copper-type mineralization in the more felsic granodiorite and granodiorite porphyry intrusions.

Optical, x-ray, and chemical analyses indicate two distinct populations of tourmaline present in the breccia pipes; an early "Hemlock Ridge-type" which …


Neoglaciation Of Avalanche Gorge And The Middle Fork Nooksack River Valley Mt. Baker, Washington, Steven Richard Fuller Jan 1980

Neoglaciation Of Avalanche Gorge And The Middle Fork Nooksack River Valley Mt. Baker, Washington, Steven Richard Fuller

WWU Graduate School Collection

The Neoglacial fluctuations of two of Mt. Baker's alpine glaciers were studied by tephrochronologic, dendrochronologic, and relative dating methods coupled with detailed geologic mapping. The earliest recognizable advance of the Deming Glacier occurred prior to deposition of Mazama tephra and after the Vashon Stade of Fraser Glaciation. The oldest recognizable Holocene advance of the Deming Glacier occurred >800 years B.P. and 16th, 17th, 18th(?), early 19th, late 19th, and 20th centuries. The Neoglacial record for the Rainbow Glacier is poorly preserved due to modification by two historic rock-debris avalanches, but the 20th century moraines of the Rainbow and Deming Glaciers …


Fossil Algae In The St. Louis Limestone, Near St. Louis, Missouri, Sherris Ragsdale Myers Jan 1980

Fossil Algae In The St. Louis Limestone, Near St. Louis, Missouri, Sherris Ragsdale Myers

Masters Theses

"Although Mississippian algae research is fairly extensive, little has been published on algae from the Mississippian type locality, the Upper Mississippi River Valley. For this study, portions of sixteen St. Louis Limestone stratigraphic sections containing units with oncolites, domal stromatolites, laminations, or mottled (possibly algal) textures, were measured, described, and sampled to determine: (1) to what extent algae are preserved in the St. Louis Limestone, (2) if enough of the delicate structure was fossilized to determine morphology, (3) depositional environment of the algae, and (4) if the algae are related to a lithologic pattern. Thin sections of the sampled units …


Heavy Metal Inventory Of Suspended Sediment And Fluid Mud In Chesapeake Bay, Richard Harris, Maynard M. Nichols, Galen Thompson, John Banacki, George Vadas Jan 1980

Heavy Metal Inventory Of Suspended Sediment And Fluid Mud In Chesapeake Bay, Richard Harris, Maynard M. Nichols, Galen Thompson, John Banacki, George Vadas

Reports

Heavy metals have been found associated with suspended material, sediments and fluid mud in the Chesapeake Bay. A series of field observations were made along the Bay axis to determine the metal concentrations and their distributions at relatively high and at average river inflow between March 27-April 9 and May 2-10, 1979.

Metal concentrations in suspended material per unit volume of water relate to the concentrations of suspended material. They are higher in the zone of the turbidity maximum than landward in river water or seaward in estuarine water. Thus, metals associated with suspended material tend to accumulate in the …


Ua66/8/3 Annual Report, Wku Geography & Geology Jan 1980

Ua66/8/3 Annual Report, Wku Geography & Geology

WKU Administration Documents

Annual report of activities of the WKU department of Geography & Geology.


Stratigraphic Relationships Of The Brentwood And Woolsey Members, Bloyd Formation (Type Morrowan), Northwest Arkansas, Thomas A. Mcgilvery, Charles E. Berlau Jan 1980

Stratigraphic Relationships Of The Brentwood And Woolsey Members, Bloyd Formation (Type Morrowan), Northwest Arkansas, Thomas A. Mcgilvery, Charles E. Berlau

Journal of the Arkansas Academy of Science

The Brentwood Member of the Bloyd Formation conformably overlies the Prairie Grove Member, Hale Formation in the type Morrowan succession of northwestern Arkansas. At its type locality, the Brentwood is separated from the underlying Prairie Grove Member by nearly 6 m of dark shale. Away from this area, the shale thins rapidly and the Hale-Bloyd boundary may be placed with difficulty. At some localities east of type section, the boundary is thought to be erosional rather than the more typical gradational contact. The Brentwood consists of discrete carbonate bodies separated by dark shales. The carbonates consist principally of open shelf …


Surface Geology For Land Use Planning, Minot, North Dakota Area, Garth S. Anderson Jan 1980

Surface Geology For Land Use Planning, Minot, North Dakota Area, Garth S. Anderson

Theses and Dissertations

The Minot area includes about 330 square kilometres along both sides of the Souris River in north-central North Dakota. The area can be divided into the flat Souris River floodplain, the steeply sloping sides of the Souris and Des Lacs meltwater channels and larger tributaries, and the gently undulating uplands dissected by small streams. Surficial geologic units include Early Tertiary sand, silt, clay, and sandstone of the Bullion Creek Formation, Pleistocene glacial till, ice contact fluvial deposits, and other fluvial deposits of the Coleharbor Group, and Holocene fluvial and eolian deposits of the Oahe Formation.

Expansion of the Minot metropolitan …


Stratigraphy, Sedimentology, And Depositional Environments Of The Hell Creek Formation (Late Cretaceous) And Adjacent Strata, Glendive Area, Montana, Raymond D. Butler Jan 1980

Stratigraphy, Sedimentology, And Depositional Environments Of The Hell Creek Formation (Late Cretaceous) And Adjacent Strata, Glendive Area, Montana, Raymond D. Butler

Theses and Dissertations

The Colgate Member (Fox Hills Formation), Little Beaver Creek, Marmarth, Bacon Creek, Huff, and Pretty Butte Members (Hell Creek Formation), and lower Ludlow Formation in the Glendive area, Montana consist of sandstone, sandy siltstone, shale, and lignite. The Colgate is 24 m thick and consists of mostly sandstone, The Hell Creek Formation (Late Cretaceous) is 120 m thick, The basal member, the Little Beaver Creek, is up to 12 m thick and consists of about half sandstone and half shale. The Marmarth is 24 to 30 m thick and consists of mostly sandstone. The Bacon Creek is 36 m thick …


Paleoenvironmental Analysis Of A Late Holocene Deposit : Stanton Site, West-Central North Dakota, David W. Fischer Jan 1980

Paleoenvironmental Analysis Of A Late Holocene Deposit : Stanton Site, West-Central North Dakota, David W. Fischer

Theses and Dissertations

The Stanton Site (W1/2NE1/4 sec. 16, T. 144 N., R. 85W.), eastern Mercer County, North Dakota, contains a late Holocene organic deposit in the cutbank of an ephemeral stream on the Missouri Plateau. Strati graphic units of the 104-cm section are, in ascending order: (l) gravel; (2) silty, organic, sandy clay; (3) organic silt; (4) silty, sandy, organic clay; (5) organic silt; (6) sandy, silt, organic clay; and (7) sand. A radiocarbon date of wood from the base of unit 2 indicates initiation of deposition at 325±_115 radiocarbon years B.P.

Abundant well-preserved fossils are present in the organic sediments of …


Kaolinitic Weathering Zone On Precambrian Basement Rocks, Red River Valley, Eastern North Dakota And Northwestern Minnesota, Lynne Irvine Kelley Jan 1980

Kaolinitic Weathering Zone On Precambrian Basement Rocks, Red River Valley, Eastern North Dakota And Northwestern Minnesota, Lynne Irvine Kelley

Theses and Dissertations

A suite of 26 drill cores recovered from the Red River Valley Drilling Project has provided new information on the Precambrian basement of eastern North Dakota and northwestern Minnesota. Basement rocks in this area consist of intermediate to felsic coarse-grained massive or gneissic rocks, and intermediate to mafic metavolcanic and metasedimentary schists. The Precambrian rocks of the region are interpreted to be a buried extension of the Superior Province of the Canadian Shield, and are divided into terranes of granitic rock and mafic schist, on the basis of drill-hole samples, patterns seen in Superior Province rocks which crop out to …


Geology And Petrology Of The Devils Tower, Missouri Buttes, And Barlow Canyon Area, Crook County, Wyoming, Don L. Halvorson Jan 1980

Geology And Petrology Of The Devils Tower, Missouri Buttes, And Barlow Canyon Area, Crook County, Wyoming, Don L. Halvorson

Theses and Dissertations

Field and laboratory investigations were employed to detmine the mode of emplacement and a petrogenetic model for three igneous localities in Crook County, Wyoming: the Devils Tower, the Missouri Buttes, and the Barlow Canyon area.

X-ray fluorescence, microprobe data, and optimal analyses iden tify the Missouri Buttes rock as foid-bearing alkali trachyte and anal cime phonolite and the Devils Tower and Barlow Canyon rocks as analcime phonolite.

Associated alloclastic breccia with a crystal-charged volcanic glass matrix, surrounding depressions representing collapse of igneous material back into the vent, striking similarity to known volcante necks, and the occurrence of other extrusive volcan1S11\ …


Authigenic Kaolinite In The Bear Den Member (Paleocene) Of The Golden Valley Formation, In Southwestern North Dakota, Gordon H. Prichard Jan 1980

Authigenic Kaolinite In The Bear Den Member (Paleocene) Of The Golden Valley Formation, In Southwestern North Dakota, Gordon H. Prichard

Theses and Dissertations

The Golden Valley Formation of North Dakota crops out in isolated remnants over a large area of southwestern North Dakota. The formation has two members, the lower Bear Den Member, which is characterized by kaolin and bright colors and the upper Camels Butte Member, which is characterized by micaceous sand and clay.

Two different theories, either in place weathering or detrital deposition, have developed as to the origin of the kaolinite in the lower member. Early workers suggest that the kaolinite of the member is detrital in origin for the following reasons:

1. No unconformity is present at the top …


Distribution And Origin Of Elongate Sandstone Concretions, Bullion Creek And Slope Formations (Paleocene), Adams County, North Dakota, Michael W. Parsons Jan 1980

Distribution And Origin Of Elongate Sandstone Concretions, Bullion Creek And Slope Formations (Paleocene), Adams County, North Dakota, Michael W. Parsons

Theses and Dissertations

Rectilinear patterns in sandstone are visible on aerial photo graphs of Adams County, North Dakota. These patterns result from the differential erosion of elongate, calcareous, sandstone concretions that have formed in fluvial channel sand units.

The distribution and orientation of the elongate concretions were mapped from aerial photographs. The concretions have a strongly east-west orientation. Averages of paleocurrent measurements of the associated sand and sandstone are also easterly.

The elongate concretions occur slightly above and below the Rhame bed (a white marker zone at the top of the Slope Formation), in sand units at the base of the Bullion Creek …


Postglacial Ostracod Distribution And Paleoecology, Devils Lake Basin, Northeastern North Dakota, James B. Van Alstine Jan 1980

Postglacial Ostracod Distribution And Paleoecology, Devils Lake Basin, Northeastern North Dakota, James B. Van Alstine

Theses and Dissertations

Sediment cores were taken from Main Bay and Creel Bay of Devils Lake (in 1975 and 1976) and East Devils Lake (in 1978), within the Devils Lake basin, and from Red Willow Lake (in 1979), a control lake outside of the Devils Lake basin, northeastern North Dakota. The cores were sampled, for the recovery of the ostracods, at 10-cm intervals. Fifteen species of ostracods were present in the studied cores: 8 candonids, 1 cyclocyprid, 3 cyprids, and 3 limnocytherids. Two distinct faunas are recognized. The Devils Lake-East Devils Lake fauna consists of Candona lactea, C. rawsoni, Cyprinotus glaucus, Potamocypris smaragdina, …


Petrology Of The Cenozoic Igneous Rocks Of The Lytle Creek Area, Bear Lodge Mountains, Wyoming, Stanely F. White Jan 1980

Petrology Of The Cenozoic Igneous Rocks Of The Lytle Creek Area, Bear Lodge Mountains, Wyoming, Stanely F. White

Theses and Dissertations

The purpose of this study was to map and study the petrology of the Cenozoic igneous rocks that crop out in the Lytle Creek area located in the southwestern Bear Lodge Mountains of northeastern Wyoming. Petro graphic and chemical data is used to interpret the Cenozoic phonolite trachyte rock association.

Cenozoic igneous activity in the Lytle Creek area appears to have been a response to the Laramide orogeny 80-40 m.y. B.P. The majority of the rocks were emplaced as laccoliths and sills at the Pahasapa Formation-Minnelusa Formation contact or at the Spearfish Formation Sundance Formation contact. Porphyritic volcanic textures are …