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Brigham Young University

Earth Sciences

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Full-Text Articles in Physical Sciences and Mathematics

The Effects Of Fault-Induced Stress Anisotropy On Fracturing, Folding And Sill Emplacement: Insights From The Bowie Coal Mines, Southern Piceance Basin, Western Colorado., Eric Dean Robeck Mar 2005

The Effects Of Fault-Induced Stress Anisotropy On Fracturing, Folding And Sill Emplacement: Insights From The Bowie Coal Mines, Southern Piceance Basin, Western Colorado., Eric Dean Robeck

Theses and Dissertations

The recognition of fault-perturbed stress fields is an important tool in areas of mineral or hydrocarbon exploration. The Bowie underground coal mines of western Colorado expose a reverse-reactivated growth fault that perturbed the stress field during cleat (fracture) formation, rotating cleat orientations up to 500 m on both sides of the fault. Two unusual fracture types are found only in coal adjacent to the fault: (1) concentric cleats, highly curved fractures that form blocks resembling balls or eggs and (2) horsetail cleats, striated surfaces that superficially resemble shattercones and result from shear failure in coal. Numerical models created with the …

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A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant Mar 2005

A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant

Theses and Dissertations

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, …

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A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau Mar 2005

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …

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Pluton Zonation Unveiled By Gamma-Ray Spectrometry And Magnetic Susceptibility; A Case Study Of The Sheeprock Granite, Western, Utah, Paul D. Richardson Nov 2004

Pluton Zonation Unveiled By Gamma-Ray Spectrometry And Magnetic Susceptibility; A Case Study Of The Sheeprock Granite, Western, Utah, Paul D. Richardson

Theses and Dissertations

A radiometric survey of the zoned 21 Ma, A-type Sheeprock granite, western Utah, combined with measurements of magnetic susceptibility and field observations were analyzed using a geographic information system. The intrusion spans 25 square km and is roughly eliptical in shape with its long axis trending northwest. Concentration maps (composed of more than 500 survey stations) of eU, eTh, texture, magnetic susceptibility, color, and joint density help to constrain magmatic and post-magmatic processes related to its chemical and physical zonation. Uranium ranges from 3.9 to 26.9 ppm (mean 12.7) and thorium from 1.7 to 125.7 ppm (mean 45.5). Similarities in …

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An Unusually Large Aulocopella Winnipegensis And Associated Demosponges From The Upper Ordovician Beaverfoot Formation, Southeastern British Columbia, J. Keith Rigby, Paul A. Johnston Aug 2004

An Unusually Large Aulocopella Winnipegensis And Associated Demosponges From The Upper Ordovician Beaverfoot Formation, Southeastern British Columbia, J. Keith Rigby, Paul A. Johnston

Faculty Publications

An unusually large specimen of the rare digitate to bladed Aulocopella winnipegensis Rauff and three relatively normal sized specimens of ashtray-shaped Hudsonospongia? sp. constitute the first record of demosponges from the Upper Ordovician Beaverfoot Formation in southeastern British Columbia and the first record of these taxa from western Canada. Gross form and canal structure are well preserved, but dolomitization and (or) coarse microsphaeroidal silicification have obliterated spicules and other structural details. We interpret these sponges as epifaunal recliners, without means of attachment to the substrate, a life mode rarely encountered in the modern sponge biota.

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Platinum Group Element Mineralization In "Ballrooms" Of The J-M Reef Of The Stillwater Complex, Montana, Matthew P. Harper Jun 2004

Platinum Group Element Mineralization In "Ballrooms" Of The J-M Reef Of The Stillwater Complex, Montana, Matthew P. Harper

Theses and Dissertations

The J-M Reef of the Stillwater Complex, Montana (a large layered mafic intrusion), is one of the highest grade platinum group element (PGE) deposits known in the world, producing primarily palladium and platinum in a 3.4:1 ratio. "Ballrooms" of the Stillwater Complex are anomalously wide areas within or stratigraphically below the J-M Reef that host platinum group element mineralization. Ballrooms have two typical morphologies (type 1 and type 2); the first is an abrupt thickening of the mineralization that extends below the Reef Package and the second is a gentle widening of the Reef Package and associated reef mineralization to …

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Delineation Of Mass Movement Prone Areas By Landsat 7 And Digitial Image Processing, Shiloh Marie Howland Dec 2003

Delineation Of Mass Movement Prone Areas By Landsat 7 And Digitial Image Processing, Shiloh Marie Howland

Theses and Dissertations

The problem of whether Landsat 7 data could be used to delineate areas prone to mass movement, particularly debris flows and landslides, was examined using three techniques: change detection in NDVI (Normalized Difference Vegetation Index), change detection in band 5, and the tasseled cap transformation. These techniques were applied to areas that had recently experienced mass movement: Layton, Davis County and Alpine, Spanish Fork Canyon and Santaquin, Utah County. No distinctive spectral characteristics were found with any of these techniques with two possible explanations: 1. That despite improved spatial resolution in Landat 7 over its predecessors and improved digital image …

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A New Occurrence Of Archaeoscyphia Pulchra (Bassler) From The Ordovician Of Western Canada, J. Keith Rigby, Godfrey S. Nowlan, Peter A. Rowlands Jan 2002

A New Occurrence Of Archaeoscyphia Pulchra (Bassler) From The Ordovician Of Western Canada, J. Keith Rigby, Godfrey S. Nowlan, Peter A. Rowlands

Faculty Publications

A few specimens of the ornate anthaspidellid demosponge, Archaeoscyphia pulchra (Bassler), have been collected from the Lower Ordovician Outram Formation or Skoki Formation, from a saddle at the head of South Rice Brook in northeastern British Columbia. This is the first report of the flanged-appearing annulate, steeply obconical sponge in western Canada, although it has been reported from the Mingan Islands of Quebec and was initially described from Nevada, in the western United States. The taxon has also been reported as other species of Archaeoscyphia from Ordovician rocks of Missouri and from the San Juan region of Argentina.

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Contributions From Mafic Alkaline Magmas To The Bingham Porphyry Cu-Au-Mo Deposit, Utah, U.S.A., Daniel T. Maughan Jul 2001

Contributions From Mafic Alkaline Magmas To The Bingham Porphyry Cu-Au-Mo Deposit, Utah, U.S.A., Daniel T. Maughan

Theses and Dissertations

The Bingham porphyry Cu-Au-Mo deposit, Utah, may only be world-class because of substantial contributions of sulfur and metals from mafic alkaline magma to an otherwise unremarkable calc-alkaline system. Volcanic mafic alkaline rocks in the district are enriched in Cr, Ni, and Ba as well as ore-related constituents of Cu, Au, platinum group elements (PGE) and S. The bulk of the volcanic section that is comagmatic with ore-related porphyries is dacitic to trachytic in composition, but has inherited the geochemical signature of high Cr, Ni, and Ba from magma mixing with the mafic alkaline rocks. The volcanic section that most closely …

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Efficiency Of The Inorganic Fertilization In The Cultivation Of Alfalfa (Medicated Sativa L) And Whitewashing For The Correction Of The Ph Of The Soil, Alex Gonzalo Bravo Morocho Jan 2001

Efficiency Of The Inorganic Fertilization In The Cultivation Of Alfalfa (Medicated Sativa L) And Whitewashing For The Correction Of The Ph Of The Soil, Alex Gonzalo Bravo Morocho

Theses and Dissertations

In our country the necessity to offer new alternatives for the agricultural sector is high-priority especially for the lucern cultivation that every day is surface cultivated especially in the Chimborazo province increases; for what is of our interest to establish the answer from the cultivation to the inorganic fertilization and liming for the flora pH correction, for this way to obtain better yields and for consequence to improve the economic conditions of the farmers. With the result that the titled investigation: Efficiency of the Inorganic Fertilization in the Alfalfa Cultivation (Medicago sativa L) and Liming for the Correction of the …

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Species Of The Cretaceous Tree Fern Tempskya From Utah, William D. Tidwell, Naomi Hebbert Sep 1992

Species Of The Cretaceous Tree Fern Tempskya From Utah, William D. Tidwell, Naomi Hebbert

Faculty Publications

Nine species of the permineralized stems of Tempskya were investigated from the Lower Cretaceous Cedar Mountain and Burro Canyon Formations, and the lower Upper Cretaceous Dakota Formation in central and southeastern Utah. Tempskya jonesii, T. stichkae, and T. readii are new and are differentiated on the basis of the radial orientation of their dorsiventral stems, their internodal lengths, the lack of sclerenchyma in the inner cortex of T. jonesii, the three nearly continuous zones of sclerenchyma in the inner cortex off T. stichkae, and the completely sclerotic inner cortex of T. readii. Specimens of T. jonesii and T. minor were …

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Tomlinsonia Stichkania Sp. Nov., A Permineralized Grass From The Pliocene To (?)Pleistocene China Ranch Beds In Sperry Wash, California, William D. Tidwell, E. M. V. Nambudiri Jun 1990

Tomlinsonia Stichkania Sp. Nov., A Permineralized Grass From The Pliocene To (?)Pleistocene China Ranch Beds In Sperry Wash, California, William D. Tidwell, E. M. V. Nambudiri

Faculty Publications

Permineralized specimens of grasses assignable to Tomlinsonia as a new species Tomlinsonia stichkania occur in the China Ranch beds of Pliocene to possible Pleistocene age in Sperry Wash in the Alexander Hills of southeastern California. The round culm of these grasses is generally solid or occasionally hollow with collateral vascular bundles in the distinct outer and indistinct inner rings. Two-ranked leaf sheaths alternately encircle and overlap the culm. Ridges and furrows occur in the abaxial surfaces of the sheaths. The epidermis of the leaf sheaths is similar to that of the culm. The leaf lamina consists of a three-layered mesophyll. …

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Aurealcaulis Crossii Gen. Et Sp. Nov., An Arborescent, Osmundaceous Trunk From The Fort Union Formation (Paleocene), Wyoming, William D. Tidwell, Lee R. Parker Jun 1987

Aurealcaulis Crossii Gen. Et Sp. Nov., An Arborescent, Osmundaceous Trunk From The Fort Union Formation (Paleocene), Wyoming, William D. Tidwell, Lee R. Parker

Faculty Publications

Aurealcaulis crossii gen. et sp. nov., is based on permineralized trunks of an osmundaceous tree fern from the Paleocene Fort Union Formation from near Bitter Creek Station of southwestern Wyoming. This new species is characterized by centripetal (exarch) development of its xylem strands which form part of the leaf traces. Most of the leaf traces depart the stele as two segments that fuse into a single C-shaped petiole vascular strand outside of the outer cortex. Stipular expansions of the petiole bases of this species lack sclerenchyma, and roots arise from the lateral edges of leaf traces in the inner cortex. …

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Pinuxylon Woolardii Sp. Nov., A New Petrified Taxon Of Pinaceae From The Miocene Basalts Of Eastern Oregon, William D. Tidwell, Lee R. Parker, Vaughn K. Folkman Nov 1986

Pinuxylon Woolardii Sp. Nov., A New Petrified Taxon Of Pinaceae From The Miocene Basalts Of Eastern Oregon, William D. Tidwell, Lee R. Parker, Vaughn K. Folkman

Faculty Publications

Specimens of the new species Pinuxylon wollardii have been collected from Miocene strata near Kurkee, OR. These petrified specimens are unique in that, due to weathering, individual tracheids and ray cells can be separated for detailed SEM studies. This species is characterized by its high number of ray cells; numerous rays; large resin ducts which are commonly paired; primarily uniseriate pitting, two to five (usually three) small, oval or cirular pinoid pits per crossfield; and smooth walls on its transverse (ray) tracheids. The latter character relates this species to taxa in the subgenus Haploxylon of Pinus. Pinuxylon woolardii is most …

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Arnoldia Kuesii, A New Juvenile Fernlike Plant From The Lower Permian Of New Mexico, William D. Tidwell, Sidney Ash Jun 1986

Arnoldia Kuesii, A New Juvenile Fernlike Plant From The Lower Permian Of New Mexico, William D. Tidwell, Sidney Ash

Faculty Publications

A nearly complete juvenile fernlike plant is described here from Lower Permian rocks of New Mexico. The fossil consists of a horizontal rhizome with roots, a short thick upright aerial branch, and a tuft of dimorphic leaves. It is assigned to Arnodia kuesii gen. et sp. n. and appears to be the first juvenile fernlike plant known from the Upper Paleozoic. Abundant palynomorphs and other plant fossils associated with the fossil indicate that it is Early Permian in age.

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Interconnected Reproductive And Vegetative Remains Of Populus (Salicaceae) From The Middle Eocene Green River Formation, Northeastern Utah, William D. Tidwell, Steven R. Manchester, David L. Dilcher Jan 1986

Interconnected Reproductive And Vegetative Remains Of Populus (Salicaceae) From The Middle Eocene Green River Formation, Northeastern Utah, William D. Tidwell, Steven R. Manchester, David L. Dilcher

Faculty Publications

A new specimen from the Middle Eocene Evacuation Creek Member of the Green River Formation in northeastern Utah shows a twig with several leaves of Populus wilmattae Crockrell and a fruiting raceme attache. This specimen establishes for the first time the type of fruits borne by P. wilmattae and provides additional characters with which to assess its taxonomic and evolutionary status. An associated seed shows attached placental hairs like those of extant species of Populus. The Green River fossil differs from extant Populus species in having basically palmate leaf venation and in bearing its fruiting axis on a young twig. …

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Flora Of The Lower Cretaceous Cedar Mountain Formation Of Utah And Colorado; Part Iii, Icacinoxylon Pittiense N. Sp., William D. Tidwell, Gregory F. Thayn, W. L. Stokes Feb 1985

Flora Of The Lower Cretaceous Cedar Mountain Formation Of Utah And Colorado; Part Iii, Icacinoxylon Pittiense N. Sp., William D. Tidwell, Gregory F. Thayn, W. L. Stokes

Faculty Publications

Icacinoxylon pittiense, a new species of angiospermous wood from the Lower Cretaceous Cedar Mountain Formation of Utah is described and compared with similar fossil and modern woods. It is distinguished from other species of Icacinoxylon by its thick-walled fiber-tracheids with their walls making up at least 50% of the total diameter of the cells, conspicuous bordered pits with obliquely crossing extended apertures on both the tangential and radial walls of its fiber-tracheids, scalariform perforation plates with as few as four or greater than 30 bars, transitional opposite to scalariform pitting on its vessel walls, thick-walled ray cells, and distinct sheath …

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Stratigraphy Of The Lower Tertiary And Upper Cretaceous (?) Continental Strata In The Canyon Range, Juab County, Utah, James M. Stolle Jan 1978

Stratigraphy Of The Lower Tertiary And Upper Cretaceous (?) Continental Strata In The Canyon Range, Juab County, Utah, James M. Stolle

Theses and Dissertations

The Canyon Range Formation (informal new name), formerly mapped as the Indianola Group within the Canyon Range, is divisible into two distinct, mappable units, A and B. Unit A is nearly all conglomerate strata, and conglomerate texture and sedimentary structures suggest an alluvial fan depositional environment. Precambrian and basal Cambrian quartzite clasts represent the erosional debris from the allochthonous Canyon Range thrust. Unit B is composed of interbedded fluvial sandstone and conglomerates with lacustrine limestones, commonly micritic and/or oncolitic. Conglomerate clasts indicate a Paleozoic carbonate provenance. Unit A, previously mapped as the Indianola, underlies Unit B and correlates with the …

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Certain Edaphic And Biotic Factors Affecting Vegetation In The Shadscale Community Of The Kaiparowits Area, Vane Orlan Campbell Mar 1977

Certain Edaphic And Biotic Factors Affecting Vegetation In The Shadscale Community Of The Kaiparowits Area, Vane Orlan Campbell

Theses and Dissertations

A study area on the southern extensions of the Great Basin cold desert (Kaiparowits Basin, Utah) was selected which has had varying amounts of disturbance. Areas with similar slope and exposure in the Shadscale community were sampled. At each site, soil samples were collected and percent sand, percent clay, percent silt, soluble salts, and hydrogen ion concentrations were measured. Cluster analysis based on percent frequency of the perennial species showed that eight groups or sub-communities were definable within the area sampled. Patterns within the vegetation were shown to be independent with the use of cluster analysis. Discriminant analysis on soil …

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The Effect Of Recreational Uses On Vegetation And Soil In The Buffalo Campground, Targhee National Forest, Island Park, Idaho, Susan Daines Foster Aug 1975

The Effect Of Recreational Uses On Vegetation And Soil In The Buffalo Campground, Targhee National Forest, Island Park, Idaho, Susan Daines Foster

Theses and Dissertations

The effect of trampling on vegetation and soil, as a result of recreational pressure, was studied in the Buffalo campground of the Targhee National Forest, Idaho. Site deterioration was most evident in the forty-two year old site. The tree stand had matured, but there were few young trees and tree reproduction had been reduced to ten seedlings per acre for Pinus contorta. Only two shrub species were sampled with a combined population of eight individuals per acre. Most of the grass species had been seeded; forbs provided 20% of the ground cover, 13% was bare ground and 71% litter. The …

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Use Of Selected Macroinvertebrates As Indicators Of Sedimentation Effects On Huntington River, Utah, Michael Kenneth Reichert Mar 1975

Use Of Selected Macroinvertebrates As Indicators Of Sedimentation Effects On Huntington River, Utah, Michael Kenneth Reichert

Theses and Dissertations

Benthic macroinvertebrate communities of Huntington River, Emery County, Utah were studied to determine effects of sedimentation from construction of Electric Lake Dam, a state highway, and two bridges. Approximately 900 benthic samples were collected from riffle areas above, in, and below the construction zone from January, 1971 to December, 1973. Two settling basins below construction sites were effective in limiting scouring of downstream communities. Heavy silt deposition was limited to a 1-km stream reach. Number of indicators, density, and biomass were reduced in the construction zone during periods of sediment input. During periods of scouring, density and biomass were reduced; …

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Conifer Wood From The Upper Jurassic Of Utah; I, Xenoxylon Morrisonense Sp. Nov., William D. Tidwell, David A. Medlyn Feb 1975

Conifer Wood From The Upper Jurassic Of Utah; I, Xenoxylon Morrisonense Sp. Nov., William D. Tidwell, David A. Medlyn

Faculty Publications

A new species of conifer wood, Xenoxylon morrisonense, is described from the Morrison Formation on the Colorado Plateau. It is compared with other species of Xenoxylon, with X. latiporosum being the closest. Xenoxylon morrisonense differs from X. latiporosum in its marked indentations, simple pits on the horizontal and tangential walls of ray cells, absence of crassulae, presence of wood parenchyma, and thin borders on podocarpoid type crossfield pits. The origin of the septa in the tracheids is summarized, and the possible affinity of Xenoxylon with the Podocarpaceae is considered.

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The Benthic Communities Of The Eastern Rocky Shore Areas Of Goshen Bay, Utah Lake, Thomas Whitney Toole Aug 1974

The Benthic Communities Of The Eastern Rocky Shore Areas Of Goshen Bay, Utah Lake, Thomas Whitney Toole

Theses and Dissertations

Information about the benthic macroinvertebrate populations along the eastern shore of Goshen Bay, Utah Lake, Utah, can be used, in part, to determine future management of the lake. In the project herein reported, cement artificial substrate samplers were used to sample two types of substrate: rubble and compacted calcareous tufa. Monthly samples were obtained from each type of substrate from March 1972 to May 1973. An amphipod, Hyalela azteca and a chironomid, Dicrotendipes fumidus were the dominant organisms in numbers and tiomass. Amphipod numbers were dependent upon the amount of algal standing crop. Elimination of this area could affect the …

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Little Drum Mountains, An Early Tertiary Shoshonitic Volcanic Center In Millard County, Utah, Stephen H. Leedom Apr 1973

Little Drum Mountains, An Early Tertiary Shoshonitic Volcanic Center In Millard County, Utah, Stephen H. Leedom

Theses and Dissertations

The Little Drum Mountains represent a deeply eroded Eocene-Oligocene volcano, consisting of a vent complex which erupted mafic flows and flow breccias, accompanied by lahars. Flows are dominated by members of the shoshonite suite and contain up to 3.95 percent K2O, mainly occult in K-rich glass, with K2O/Na2O ratios greater than 1.0. In a few interbedded flows, apparently of the calc-alkaline series, pyroxene with varying amounts of plagioclase in a fine-grained groundmass of plagioclase, mafic minerals, and interstitial glass. An ash-flow tuff of the Oligocene Needles Range Formation unconformably overlies the volcanic sequence. Contemporaneous …

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Factors That Influenced Homesteading And Land Abandonment In San Juan County, Utah, Melvin J. Frost Jan 1960

Factors That Influenced Homesteading And Land Abandonment In San Juan County, Utah, Melvin J. Frost

Theses and Dissertations

Homesteading in San Juan County, Utah is for the most part, located on Sage Plain at elevations between 6,000 to 7,200 feet. Sage Plain is an undulating surface deeply dissected with canyons. The soil is relatively shallow and the predominant vegetation is pinyon, juniper, sage brush and blue-stem grass.

The 52 year mean precipitation is 15.47 inches. Since the beginning of weather records there has been a noticeable decrease in the annual precipitation. There is generally sufficient moisture to mature winter wheat. Pinto beans are also grown in the more favorable locations.

Principle factors that have influenced homesteading and land …

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Early History Of Malad Valley, Glade F. Howell Jan 1960

Early History Of Malad Valley, Glade F. Howell

Theses and Dissertations

The Malad Valley is geographically located in a unique position in the Pacific Northwest. The Bear River and its main affluent, the Malad River, are the only rivers in the Pacific Northwest that drain into the Great Basin, whereas the other streams and rivers of the states of Washington, Idaho, and Oregon empty eventually into the Pacific Ocean. It is also characterized for being the northern end of prehistoric Lake Bonneville, and eventually it was through this valley that an outlet opened to drain the lake. The soil deposits from this lake left a fertile valley, capable of producing most …

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Early History Of Millard County And Its Latter-Day Saint Settlers, 1851-1912, Ladd R. Cropper Jan 1954

Early History Of Millard County And Its Latter-Day Saint Settlers, 1851-1912, Ladd R. Cropper

Theses and Dissertations

Millard County, Utah is located one hundred and fifty miles south of Salt Lake City in the west central part of the state. The county is bounded on the north by Juab County, on the west by Nevada, on the south by Beaver County, and on the east by Sevie, Sanpete, and Juab Counties.

There are interesting formations of extinct volcanoes. Fossils can be found and well marked evidences of an ancient lake named Bonneville.

A short account of the early explorer, Father Escalante, is given in the thesis. This tells of his travels in Millard County in the year …

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