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Hyperspectral Remote Sensing Of Potential Mineral Resources At Elephant Mountain, Interior Alaska, Khawaja Ahad Javed
Hyperspectral Remote Sensing Of Potential Mineral Resources At Elephant Mountain, Interior Alaska, Khawaja Ahad Javed
Geosciences
This study explores the application of hyperspectral remote sensing for mineral mapping purposes at Elephant Mountain, Interior Alaska, focusing on airborne and laboratory-based spectroscopic techniques. Hyperspectral imaging (HSI) was conducted using the HySpex imaging system, acquiring airborne hyperspectral imagery over an area of proven mineral resources. The research aimed to evaluate the effectiveness of HSI in identifying alteration minerals, considering the impact of spatial resolution, sensor altitude, and spatial resampling on mineral detection accuracy. A spectral feature-fitting algorithm within the USGS-developed PRISM software was employed to compare airborne-derived spectra with USGS spectral library standards. Laboratorybased spectrometric analyses of rock samples …
Bedrock Geologic Mapping Of The Willow Creek Area And Deformational History Of The Hatcher Pass Schist, Southern Talkeetna Mountains, Alaska, Isabella P. Muller
Bedrock Geologic Mapping Of The Willow Creek Area And Deformational History Of The Hatcher Pass Schist, Southern Talkeetna Mountains, Alaska, Isabella P. Muller
Geosciences
The Willow Creek area in the southernmost Talkeetna Mountains of south-central Alaska is the southern extent of the Wrangellia composite terrane (WCT). Most of south-central Alaska represents a subduction-accretion complex built upon the southern WCT. The purpose of this project is to better constrain the origin and evolution of the Hatcher Pass schist (HPs), a regionally retrogressed chlorite-muscovite schist with plagioclase and garnet porphyroblasts in the Willow Creek area. I conducted bedrock mapping of the Willow Creek area along with structural and petrographic analyses to better constrain the petrogenetic and structural history of the HPs, its contact with forearc sediments …
Effects Of Target Properties On The Formation Of Lunar Impact Craters In The Simple-To-Complex Transition, Mitali Chandnani
Effects Of Target Properties On The Formation Of Lunar Impact Craters In The Simple-To-Complex Transition, Mitali Chandnani
Geosciences
The transition from simple to complex crater morphology in impact craters with increase in crater size has been modelled and observed in planetary bodies across the Solar System. The transition diameter depends upon the strength and gravity of the planetary body. On the Moon, this transition takes place over a diameter range of several kilometers. This range spans a diversity of crater morphologies including simple, transitional and complex craters. The diameter range of 15 20 km falls within the lunar simple-to-complex transition. All other impactor properties held constant, the 15-20 km range corresponds to a factor of three in the …
Natural Fracture Character And Distribution Adjacent To The Nenana Basin, Central Alaska, Alec J. Rizzo
Natural Fracture Character And Distribution Adjacent To The Nenana Basin, Central Alaska, Alec J. Rizzo
Geosciences
The NE-trending Nenana basin is a Cenozoic-aged basin located in central Alaska between the Denali and Tintina fault systems. The narrow, deep basin is a current exploration target for oil and gas resources in Interior Alaska. Natural fractures were analyzed to further understand larger structural features such as faults and folds related to the structural evolution of the Nenana basin and surrounding areas. Fracture sets were measured and described on the margin of the basin at four field locations: the Fairbanks area, along the Parks Highway between Fairbanks and Nenana, and in outcrop around the Nenana and Healy areas. In …
Petrologic And Geochemical Tracers Of Magmatic Movement In Volcanic Arc Systems: Case Studies From The Aleutian Islands And Kamchatka, Russia, Owen Kelly Neill
Petrologic And Geochemical Tracers Of Magmatic Movement In Volcanic Arc Systems: Case Studies From The Aleutian Islands And Kamchatka, Russia, Owen Kelly Neill
Geosciences
Mixing, crystallization and degassing commonly affect magmas during storage, ascent and eruption from volcanoes. As these interactions cannot be observed directly, they must be characterized using chemical signatures of volcanic eruptive products. In this dissertation, geochemical tracers of magma mixing, crystallization and degassing were employed to investigate the magmatic systems of Kasatochi Island volcano, central Aleutian Islands, and Bezymianny Volcano, Kamchatka, Russia, in three studies. The purpose of the first study was to characterize eruptive products from the 2008 eruption of Kasatochi Island volcano. This eruption produced pumiceous, medium-K andesite, as well as denser, medium-K basaltic andesite, with variable bulk …
Depositional Systems, Paleoclimate, And Provenance Of The Late Miocene To Pliocene Beluga And Sterling Formations, Cook Inlet Forearc Basin, Alaska, Jacob Mongrain
Geosciences
The sedimentary record of forearc basins provides critical clues to the complex geologic history of subduction zones. This study focuses on Cook Inlet forearc basin, part of a larger forearc basin complex in southern Alaska. Specifically, I investigated the sedimentology, paleoclimate, and provenance of the Beluga and Sterling formations, comprising the late Miocene to Pliocene Cook Inlet basin record. These interpretations are used to reconstruct the Miocene-Pliocene basin history and better understand forearc development. Before ~11 Ma anabranching/single channel depositional systems of the Beluga Fm. deposited sediment on the western and eastern margins of Cook Inlet. Sandstone compositional data suggest …
Active Tectonics In Southern Alaska And The Role Of The Yakutat Block Constrained By Gps Measurements, Julie Elliott
Active Tectonics In Southern Alaska And The Role Of The Yakutat Block Constrained By Gps Measurements, Julie Elliott
Geosciences
GPS data from southern Alaska and the northern Canadian Cordillera have helped redefine the region's tectonic landscape. Instead of a comparatively simple interaction between the Pacific and North American plates, with relative motion accommodated on a single boundary fault, the margin is made up of a number of small blocks and deformation zones with relative motion distributed across a variety of structures. Much of this complexity can be attributed to the Yakutat block, an allochthonous terrane that has been colliding with southern Alaska since the Miocene. This thesis presents GPS data from across the region and uses it to constrain …
Geologic Setting Of The Central Alaskan Hot Springs Belt: Implications For Geothermal Resource Capacity And Sustainable Energy Production, Amanda M. Kolker
Geologic Setting Of The Central Alaskan Hot Springs Belt: Implications For Geothermal Resource Capacity And Sustainable Energy Production, Amanda M. Kolker
Geosciences
The Central Alaskan Hot Springs Belt (CAHSB) is a vast stretch of low-temperature hydrothermal systems that has the potential to be a geothermal energy resource for remote communities in Alaska. Little exploration has occurred in the CAHSB and the resource is poorly understood. A geothermal power plant was installed in 2006 at Chena Hot Springs (CHS), one of the 30-plus hot springs in the CAHSB. This, in addition to the multiple direct use projects at CHS, could serve as a model for geothermal development elsewhere in the CAHSB. This dissertation evaluates the geologic setting of the CAHSB and explores the …
Stratigraphy, Structure, And Origin Of The Mendeleev Ridge From Bathymetry, Controlled Source Seismic, And Gravity Observations, Dayton W. Dove
Stratigraphy, Structure, And Origin Of The Mendeleev Ridge From Bathymetry, Controlled Source Seismic, And Gravity Observations, Dayton W. Dove
Geosciences
Multi-channel-seismic (MCS), seismic refraction, and gravity data collected over the Mendeleev Ridge have been processed and interpreted to describe the crustal style of the ridge, as well as the structural and depositional history. These results provide constraints on the origin of the ridge, and the tectonic evolution of the Amerasian Basin. MCS images reveal two primary sediment sequences separated by an unconformity that persists across the entire Mendeleev Ridge. The basement and lower sediment sequence exhibit pervasive normal faulting and the regional unconformity is interpreted to mark the end of extensional deformation. Modeling of the seismic refraction data reveals an …
Neotectonic Framework Of The North-Central Alaska Range Foothills, Sean Patrick Bemis
Neotectonic Framework Of The North-Central Alaska Range Foothills, Sean Patrick Bemis
Geosciences
The northern foothills of the Alaska Range form a northward-convex salient at the apex of this orogen and the Denali fault. Despite the proximity of the northern foothills to the Denali fault and several historic large-magnitude earthquakes, the tectonic framework of this region has not been well-studied. A distinct pattern of east-trending folds and faults exists in both the bedrock and the geomorphic features. To assess the active structures of the region, I interpreted previous geologic mapping, developed cross-sections across the foothills belt, analyzed topographic and stream profiles, mapped the sequence of Quaternary fluvial terraces, and performed GPS transects across …
Post-Caldera Eruptions At Okmok Volcano, Umnak Island, Alaska, With Emphasis On Recent Eruptions From Cone A, Delenora M. Grey
Post-Caldera Eruptions At Okmok Volcano, Umnak Island, Alaska, With Emphasis On Recent Eruptions From Cone A, Delenora M. Grey
Geosciences
Okmok volcano has undergone two caldera-forming eruptions, 12,000 and 2050 BP, and has been quite active in historic time. The historic eruptive record has been compiled and augmented with descriptions and photographs of recent eruptions. Eruptions in 1958 and 1997 produced the first post-caldera lava flows to traverse most of the caldera floor. The source of these flows, Cone A, has been constructed largely during the 20th century. Major element analysis of lavas from eight major intracaldera cones reveals two chemically and spatially separate trends, which suggest two separate magma sources beneath the caldera, one feeding an arc of cones …
Lateral Magma Transport During The 1912 Eruption Of Novarupta: Insights From Magnetic Imaging, Graham J. Hill
Lateral Magma Transport During The 1912 Eruption Of Novarupta: Insights From Magnetic Imaging, Graham J. Hill
Geosciences
The Valley of Ten Thousand Smokes (VTTS), on the Alaska Peninsula, was formed by the cataclysmic eruption of Novarupta (Katmai) in 1912. During the eruption, three magma types were tapped (7-8 km³ of rhyolite, 4.5 km³ of dacite, and 1 km³ of andesite). Contemporaneous collapse of Mount Katmai while Katmai-like andesite and dacite magma joined the eruption at Novarupta provides incontrovertible evidence for magma transport from beneath Mount Katmai caldera to the vent 10 km west at Novarupta (Hildreth and Fierstein, 2000). Shallow storage of the andesite and dacite magmas beneath Mt. Katmai prior to the eruption of 1912 is …
Modeling Of Permafrost And Gas Hydrate Stability Zone Within Alaskan Arctic Shelves And Continental Margins, Sergei I. Pokrovsky
Modeling Of Permafrost And Gas Hydrate Stability Zone Within Alaskan Arctic Shelves And Continental Margins, Sergei I. Pokrovsky
Geosciences
A mathematical model was used to determine the behavior of the thermal regime and temperature and pressure conditions due to climate and sea level variations of the gas hydrate stability zone formation at four sites within the Alaskan Arctic Shelf. Two soil types, coarse-grained and fine-grained, and three types of programs were used. The programs were distinguished by whether or not they took unfrozen water and latent heat into account. Simulations suggest the presence of subsea permafrost in a vast area of shelf near Prudhoe Bay. Near Barrow and Lonely subsea permafrost extends up to several tens of kilometers offshore, …
Upper Crustal Structure Of Southern Alaska: An Interpretation Of Seismic Refraction Data From The Trans-Alaska Crustal Transect, Lorraine W. Wolf
Upper Crustal Structure Of Southern Alaska: An Interpretation Of Seismic Refraction Data From The Trans-Alaska Crustal Transect, Lorraine W. Wolf
Geosciences
Seismic refraction and wide-angle reflection data from the U.S. Geological Survey's Trans-Alaska Crustal Transect is used to investigate the upper crustal structure of southcentral Alaska. The data consist of two intersecting refraction lines: the 135-km Chugach profile which follows the E-W strike of the Chugach Mountains and the 126-km Cordova Peak profile which follows the N-S regional dip. The four shots of the Chugach profile and the five shots of the Cordova Peak profile were recorded on 120 portable seismic instruments spaced at 1-km intervals. Interpretation of data from the Chugach terrane indicates that near-surface unconsolidated sediment and glacial ice …
Paleomagnetism And Paleogeography Of Cretaceous Northern Alaska, William Karl Witte
Paleomagnetism And Paleogeography Of Cretaceous Northern Alaska, William Karl Witte
Geosciences
No abstract provided.
Geothermal Investigations At Manley Hot Springs, Alaska, Jennifer S. East
Geothermal Investigations At Manley Hot Springs, Alaska, Jennifer S. East
Geosciences
No abstract provided.