Geology Commons^™

Structural And Biological Analysis Of Faults In Basalts In Sheepshead Mountains, Oregon As An Earth Analogue To Mars, Allison Bohanon

Theses and Dissertations

Microbial life on Mars is not visible from orbit or by rover cameras, but the fracture networks and scarp morphologies associated with fractures they could live in are measurable. We conducted a field analogue study of 92 normal fault scarps in the Sheepshead Mountains, Oregon to examine the correlation between scarp morphology and vegetation growth in the Steens Basalt. While vegetation is not expected on Mars, the fracture networks that sustain vegetation offer the same micro-environment that would support and protect endoliths. Structural variables were measured in the field and infrared spectra of fault scarps were measured using a handheld …

Exceptional Agate Formation Found In Spokane Basalt, Matthew J. Markus

2022 Symposium

People don’t normally associate semi-precious gems with basalt or the “boring black rock” that dominates the Eastern Washington landscape. However, a site just northeast of Cheney in the West Planes of Spokane, shows where a system of gem-filled veins can be found nestled into the 16-million-year-old (Kasbohm and Schoene, 2018) Priest Rapids Member of the Wanapum Basalt that is a part of the greater Columbia River Basalt. The volcanic rocks are the host to millimeter - 10 cm wide fractures with variable colored agate and opal.

Geochemical Investigation Of Monogenetic Volcanoes From The Pribilof Islands, Bering Sea, Alaska, Clayton L. Reinier

MSU Graduate Theses

Small-volume basaltic magmas found at continental intraplate environments have not been as extensively studied compared to their polygenetic counterparts. Specifically, regions such as the Bering Sea basalt province, described as a diffuse igneous province, have commonly been overlooked. Assumptions that these systems are invoked by simple, single batches of magma has subsequently left a gap in understanding the processes responsible for primary magma generation away from plate boundaries with little tectonic influence. The following studies that constitute this thesis focus on an in-depth geochemical investigation at the crystal and sub-crystal scale to evaluate lithospheric mantle heterogeneities, processes that govern primary …

Experimental Alteration Of Venusian Surface Basalts In A Hybrid Co2-So2 Atmosphere, Robert B. Reid

Masters Theses

Venus’ surface and interior dynamics remain largely unconstrained, due in great part to the major obstacles imposed by its 470°C, 90 bars surface conditions and its thick, opaque atmosphere. Orbiter-based thermal emission data provide an opportunity to characterize the Venus surface. However, interpretations of such spectra critically depend on understanding interactions between the planet’s surface basaltic rocks and its caustic, SO₂-bearing CO₂ atmosphere. Several studies, using remote sensing, thermodynamic modeling, and laboratory experiments have placed constraints on alteration mineralogies and rates. Yet constraint with respect to SO₂-mediated reactions with basalts of contrasting compositions remains incomplete. …

Interpretations Of Lava Flow Properties From Radar Remote Sensing Data, Gavin Douglas Tolometti, Catherine Neish, Gordon R. Osinski, Scott S. Hughes, Shannon E. Kobs-Nawotniak

Earth Sciences Publications

The surface morphology and roughness of a lava flow provides insight on its lava properties and emplacement processes. This is essential information for understanding the eruption history of lava fields, and magmatic processes beneath the surface of Earth and other planetary bodies such as the Moon. The surface morphology is influenced by lava properties such as viscosity, temperature, composition, and rate of shear. In this work, we seek to understand how we can interpret the emplacement processes and lava properties of lava flows using remote sensing data. Craters of the Moon (COTM) National Monument and Preserve in Idaho hosts a …

Evaluation Of The Geothermal Potential Of The Western Snake River Plain Based On A Deep Corehole On The Mountain Home Afb Near Mountain Home, Idaho, Thomas E. Lachmar, Thomas G. Freeman, James Andrew Kessler, Joseph F. Batir, James P. Evans, Dennis L. Nielson, John W. Shervais, Xiwei Chen, Douglas R. Schmitt, David D. Blackwell

Geosciences Faculty Publications

A geothermal exploration corehole was drilled to a total depth of 1821.5 m on the Mountain Home Air Force Base near Mountain Home, Idaho. The corehole was used to collect an unusually large amount of data, including uniaxial compressive stress (UCS) experiments on core samples, to evaluate the geothermal potential of the western Snake River Plain. In addition, unlike many exploration holes in this region, a fluid entry was encountered at 1745.3 m and flowed artesian to the surface. A maximum temperature of 149.4 °C was calculated for the entry. A temperature log run on the corehole from 3 to …

Volcanic Stratigraphy And Age Model Of The Kimama Deep Borehole (Project Hotspot): Evidence For 5.8 Million Years Of Continuous Basalt Volcanism, Central Snake River Plain, Idaho, Katherine E. Potter, Duane E. Champion, Robert A. Duncan, John W. Shervais

Geosciences Faculty Publications

The Snake River Plain of central Idaho represents the world’s best example of a mantle hotspot track impinging upon continental crust and provides a record of bimodal volcanism extending over 12 Ma to the present. Project Hotspot recovered almost 2 km of continuous drill core from the Kimama borehole, located in central Idaho on the axial volcanic zone. The Kimama drill core represents the most complete record of mafic volcanism along the Yellowstone–Snake River Plain hotspot track.

A total of 432 basalt flow units, representing 183 basalt flows, 78 basalt flow groups, and 34 super groups, along with 42 sediment …

Identifying Key Factors Affecting Translational Landslides In Part Of The Yakima Fold And Thrust Belt, Washington State, Joseph Schilter

All Master's Theses

Washington has one of the fastest growth rates in the nation, and unfortunately also is among the most landslide-prone states. With increased population density and urban sprawl, the need for landslide hazard assessment grows. On the Columbia Plateau in central Washington, the smooth rigid, inclined surfaces of the Columbia River Basalts (CRBs) with loose sediment layers between them induces landslides of large blocks of bedrock. These hazards remain poorly understood, but their significance was heightened by the 2017 Rattlesnake Hills Landslide that currently threatens a community and an interstate highway south of Yakima, Washington. I propose that the strongest influences …

Craters Of The Moon National Monument Basalts As Unshocked Compositional And Weathering Analogs For Martian Rocks And Meteorites, Christopher T. Adcock, Arya Udry, Elisabeth M. Hausrath, Oliver Tschauner

Geoscience Faculty Research

The availability of terrestrial sites that are martian analogs allows researchers to investigate Mars using knowledge gained on Earth. Among the terrestrial analog sites for Mars is Craters of the Moon National Monument (COTM) in Idaho, U.S.A. Craters of the Moon National Monument is home to over 60 basalt lava flows, many of which have been dated from 2050 to 18 340 years before present (y.b.p.). Following previous authors, we examined the chemistry and petrogenesis of COTM basalts compared to basaltic martian rocks, martian meteorites, and meteorite clasts, and then examined the results of chemical weathering of the basaltic flows. …

Investigating The Effect Of Magma Viscosity Changes On The Eruption Style Of Masaya Caldera Complex, Nicaragua, Garima Lohani

Graduate Research Theses & Dissertations

The Masaya caldera complex is a basaltic shield volcano that has produced rare basaltic Plinian eruptions (BPE) but is characterized by effusive activity in the last 6000 years. More than two million people live within a 20 km radius of the caldera. Magma viscosity plays an important role in determining the eruption style of a volcano. In this thesis, I provide the first viscosity measurements on an erupted magma composition and examine the role of magma viscosity in determining eruptive style at Masaya and in promoting BPE’s.

Viscosity experiments were conducted for a Masaya lava sample at superliquidus, subliquidus and …

Giant Plagioclase In The Steens Basalt, Se Oregon: Cumulate Entrainment Revealed By Textural And In Situ Chemical Analysis, Conner H. Toth

All Master's Theses

Many of the lava flows comprising the Steens Basalt in SE Oregon, the oldest and most mafic formation of the Columbia River Basalt Group (CRBG), contain exceptionally large (up to 5 cm) and abundant (up to 40 modal %) plagioclase crystals. This thesis presents a model for giant plagioclase formation in a complex system that integrates petrographic and in situ plagioclase compositional analyses with whole-rock data and computational modeling to explain systematic textural and chemical differences between plagioclase of the lower and upper Steens Basalt sub-sections. Lower Steens plagioclase are typically more chemically homogenous than upper Steens plagioclase and exhibit …

Effect Of An 860-M Thick, Cold, Freshwater Aquifer On Geothermal Potential Along The Axis Of The Eastern Snake River Plain, Idaho, Thomas E. Lachmar, Thomas G. Freeman, Christopher J. Sant, Jeffrey R. Walker, Joseph F. Batir, John W. Shervais, James P. Evans, Dennis L. Nielson, David D. Blackwell

Geosciences Faculty Publications

A 1912-m exploration corehole was drilled along the axis of the eastern Snake River Plain, Idaho. Two temperature logs run on the corehole display an obvious inflection point at about 960 m. Such behavior is indicative of downward fluid flow in the wellbore. The geothermal gradient above 935 m is 4.5 °C/km, while the gradient is 72–75 °C/km from 980 to 1440 m. Projecting the higher gradients upward to where they intersect the lower gradient on the temperature logs places the bottom of the cold, freshwater Snake River Plain aquifer, which suppresses the geothermal gradient at this location, at least …

The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The objective of this research project in Gem Valley graben, southeast Idaho is to identify the location, age and history of the Quaternary diversion of the Bear River into paleo-Lake Thatcher, and then into the Lake Bonneville basin from the Columbia River basin. Mapping, geochemical analysis, cross-cutting relationships, and five new age determinations, together with prior published research, shed new light on the complex history of interaction between the volcanic rocks, rivers, lakes, and faults in Gem Valley. Research goals were to test the hypothesis that local faulting and volcanism drove the diversion of the Bear River and controlled the …

Weathering Sequence Of Young Basalts: A Case Study From Kohala, Hawaii, Kimberly Francis Sowards

Theses and Dissertations

Exposed weathering profiles of a series of Pololu lava flows in Kohala, Hawaii are ideal for investigating the sequence of reactions/reaction pathways of weathered basalt. Weathering reactions for saprolites show mineral sequences that include feldspar → halloysite ± gibbsite + solutes; clinopyroxene → hematite + minor halloysite + solutes; olivine → hematite + solutes; magnetite → hematite or other Fe-oxides/hydroxides. However, the presence of smectite in four samples suggests that smectite-group clays may form as short lived intermediates at the base of the weathering profile. Regionally, on Kohala, soils and saprolites are dominated by halloysite with small quantities of other …

Volatiles In Subglacially Erupted Basaltic Glasses And Their Use In Reconstructing Paleo-Ice Thicknesses, Carver Lee

Masters Theses

Volatile concentrations in basaltic tuyas, edifices that form during a subglacial eruption and remain once the ice sheet has retreated, have been used to calculate the thickness of the overlying ice sheet at the onset of the eruption (Tuffen, 2010). However, subglacial eruptions are complex events and this technique does not always provide a clear answer (Schopka et al., 2006; Edwards et al., 2009). The purpose of this research is to evaluate this technique and investigate constraints on the quality of data collected by attempting to calculate the minimum ice thickness under which Hlöðufell, a tuya in south-central Iceland, erupted. …

Glaciovolcanic Megapillows Of Undirhliðar, Reykjanes Peninsula, Southwestern Iceland, Rachel Heineman

Honors Papers

At Undirhliðar tindar on the Reykjanes Peninsula, southwestern Iceland, megapillows are among the features formed during a series of ridge-building glaciovolcanic eruptions. Mapping of the northeastern 3 km of the ridge and petrographic and geochemical analysis of the megapillow outcrops occurring throughout this area demonstrate their role in the multi-stage construction of the ridge modeled by Pollock et al. (2014). The outcrops exhibit radial jointing, bands of vesicles and glassy rims, they occur in high relief surrounded by basalt breccia resembling pillow rubble, and are composed of plagioclase-phyric olivine basalt with plagioclase-rich groundmass. They occur in multiple pillow lava units …

Timing And Source Of Alkali Enrichment At Mt. Etna, Sicily: Constraints From Clinopyroxene Geobarometry And In Situ Sr Isotope Data, Kaitlyn Nelson

All Master's Theses

Since 1971, Mt. Etna, Europe’s largest and most active volcano, has exhibited increased eruption frequency and explosivity. Associated with this increased activity, researchers have documented higher abundances of alkali elements (K, Rb, Cs) as well as elevated ⁸⁷Sr/⁸⁶Sr in Etnean lavas. The source of this alkali-enrichment has been hotly debated, with end-member hypotheses involving mantle vs. crustal contributions. To further characterize the evolution of the subvolcanic magma storage and transport system, as well as the timing and source of alkali-enrichment, clinopyroxene from ten samples erupted between 1329 and 2004 was targeted for in situ textural, major element …

Exploring Martian Magmas: From The Mantle To The Regolith, Arya Sigrid Waltraud Udry

Doctoral Dissertations

The planet Mars is geologically more similar to Earth than to other planets of the solar system. For the past 50 years, new rovers, orbital spacecraft, and new martian meteorites have helped us to understand the geological processes that occurred on Mars. In this dissertation, I investigate a wide range of martian igneous compositions, such as shergottite and nakhlite meteorites, Gusev and Gale surface basalts, and the Northwest Africa (NWA) 7034 breccia. I attempt to better understand magmatic processes that occurred in the martian mantle and crust as well as surficial processes using various petrologic and geochemical tools.

As shown …

Using Paleomagnetism To Unravel The Mysteries Of The Summit Creek Basalts, Glynis Bawden

Summer Research

The Summit Creek Basalts are a sequence of steeply dipping subaerial late Eocene basaltic flows located southeast of Washington’s Mount Rainier. Despite previous petrologic and paleomagnetic investigations, the origins of these basalts are poorly understood. It is uncertain whether they erupted in situ or were transported to their present location by tectonic processes. It is possible that these lavas were derived from the same magma source as a sequence of flows in the Crescent Formation on the Olympic Peninsula, as both erupted between 45 and 50 million years ago and have similar chemical compositions. A new paleomagnetic analysis of the …

Emplacement Of Pleistocene Basalt Flows Near Mccoy, Colorado, Andrea Bowen

Electronic Theses and Dissertations

No abstract provided.

Subsurface Imaging And Petrophysical Analysis Of The South Georgia Rift Basin, South Carolina, Olusoga Martins Akintunde

Theses and Dissertations

The Triassic-Jurassic South Georgia Rift (SGR) basin, buried beneath Coastal Plain sediments of southern South Carolina, southeastern Georgia, western Florida, and southern Alabama, consists of an assemblage of continental rift deposits (popularly called red beds), and mafic igneous rocks (basalt flows and diabase sills). The red beds are capped by basalts and/or diabase sills, and constitute the target for supercritical CO2 storage as part of a Department of Energy funded project to study feasibility for safe and long-term sequestration. This study addresses key stratigraphic, structural and petrophysical issues critical to determine subsurface suitability for CO2 storage as well as improved …

Mineral Chemistry Of Basalts Recovered From Hotspot Snake River Scientific Drilling Project, Idaho: Source And Crystallization Characteristics, Richard W. Bradshaw

Theses and Dissertations

Mineral chemistry and petrography of basalts from the Kimama drill core recovered by Hotspot: Snake River Scientific Drilling Project, Idaho establish crystallization conditions of these lavas. Twenty-three basalt samples, from 20 individual lava flows were sampled from the upper 1000 m (of the 1912 m drilled) core drilled on the axis of the Snake River Plain, and represent approximately 3 m.y. of volcanism (rocks at the bottom of the hole are ~6 Ma). Rock from the upper 1000 m are typically fresh, while those lower in the core are more altered and are less likely to preserve fresh phenocrysts to …

Geothermal Alteration Of Basaltic Core From The Snake River Plain, Idaho, Christopher Joseph Sant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Snake River Plain is located in the southern part of the state of Idaho. The eastern plain, which this study focuses on, is a trail of volcanics from the Yellowstone
hotspot. Three exploratory geothermal wells were drilled on the Snake River Plain. This project studies basaltic core from the first well at Kimama, north of Burley, Idaho. The objectives of this project are to establish zones of geothermal alteration and analyze the potential for geothermal power production near the center of the Snake River Plain. Thirty samples from 1,912 m of core were sampled and analyzed. Mineral data, temperature …

Magma Chamber Processes At Mutnovsky Volcano, Russia, Kelly L. Robertson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is composed of two manuscripts about the evolution of Mutnovsky Volcano in Kamchatka, Russia. Mutnovsky has been active for the past approximately 80,000 years, during which there was the formation and subsequent eruption of four major stratocones. These four eruptive centers, named Mutnovsky I, II, III, and IV from oldest to youngest, have a range of erupted product compositions from basalt to dacite. The first major goal of this project was to investigate the melt source for Mutnovsky. Whole rock trace element and Nd, Sr, and Pb isotopic data were used to determine that the melt source was …

Assessing The Potential For Luminescence Dating Of Basalts, S. Tsukamoto, G. A.T. Duller, A. G. Wintle, Daniel R. Muhs

United States Geological Survey: Staff Publications

The possibility of dating basalt using luminescence was tested on four samples with independent age control from Cima volcanic !eld, California, with the ultimate aim of assessing whether the technique could be used to date sediments on the surface of Mars. Previous analysis of these samples had demonstrated that the infrared stimulated luminescence (IRSL) signal is most suitable for dating as it showed the lowest fading rate among various luminescence signals. In this study, changes in equivalent dose as a function of preheat are described. The ages for the two youngest Cima samples agree with the independent ages based on …

Along-Strike Trace Element And Isotopic Variation In Aleutian Island Arc Basalt: Subduction Melts Sediments And Dehydrates Serpentine, Brad S. Singer, Brian R. Jicha, William P. Leeman, Nick W. Rogers, Matthew F. Thirlwall, Jeffrey G. Ryan, Kirsten E. Nicolaysen

Geology Faculty Publications

Trace element and Sr-Nd-Pb isotope compositions of basaltic lavas from 11 volcanoes spanning 1300 km of the Aleutian Island arc provide new constraints on the recycling of elements in melts and fluids derived from subducted oceanic crust and sediment. Despite a nearly twofold variation in the flux of sediment subducted along the Aleutians, proxies indicating the presence of sediment melt in the magma source, including Th/La and Th/Nd, do not vary systematically along strike. In contrast, ratios including B/La, B/Nb, B/Be, Cs/La, Pb/Ce, and Li/Y suggest that the quantity or composition of fluid transferred from the slab into the mantle …

Geology And Geochemistry Of Tertiary Volcanic Rocks In The Northern Reveille And Southern Pancake Ranges, Nye County, Nevada, Kelly Brian Rash

UNLV Theses, Dissertations, Professional Papers, and Capstones

The northern Reveille and southern Pancake Ranges, located in the south-central Great Basin, experienced a prolonged history of Tertiary volcanism. Volcanic activity in this area began with the eruption of large-volumes of ash-flow tuffs from calderas of the central Nevada caldera complex. The Reveille Range and the southernmost portion of the Pancake Range are the site of two calderas that are the sources for the tuff of Goblin Knobs and tuff of northern Reveille Range. The tuff of Goblin Knobs (70.4-75.3 wt.% SiO₂) erupted from the caldera of Goblin Knobs (25.6 Ma) and is the thickest (~1700 m) …

Mafic Volcanism In The Colorado Plateau: Basin And Range Transition Zone, Hurricane, Utah, Alexander Sanchez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Hurricane volcanic field (HVF) is a small-volume (0.48 km³) mafic volcanic field in the Colorado Plateau/Basin & Range Transition Zone located in the eastern part of the St. George basin in southwestern Utah. Strombolian-Hawaiian style eruptions produced thin (10 m) a'a lava flows and cinder (scoria) cones composed of vesicular basalt, bombs and agglutinate. Radiometric dating and geologic relationships demonstrate that the HVF formed over a period of at least 100,000 years. In the upper crust, magma probably rose along joints in sedimentary rocks because chains of volcanic vents follow joint orientation maxima in sedimentary rocks.

Three …

An Experimental Petrologic And Geochemical Study Of Deccan Trap Basalts : Part I, Deccan Traps From Tamia, Central India ; Part Ii, Crystallization Relationships Of Deccan Basalts At 6.35 Kbars, Tobi Helene Cohen

FIU Electronic Theses and Dissertations

New major, minor, and trace element data for the Chakhla- Delakari sill and three nearby lava flows in the proximal area of Tamia are presented. Based on abundances of trace elements, it is inferred that the sill was the feeder of the two uppermost lava flows which tapped magmas from a LREE-, Rb-enriched source. The oldest (lowermost) flow shows greater affinity with the western Deccan lavas. The association of the feeder sill with a large network of parallel trending sills and dikes, and the elongate Satpura Dome, is taken to infer that a major locus of eruption of the Deccan …

Petrology Of Pliocene (?) Basalts Of Curlew Valley (Box Elder Co.), Utah, Steven Brent Kerr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Basalt outcrops in Curlew Valley consist of several flow remnants and eruptive centers situated along the valley margins. Basalt is also found in association with salic rocks that erupted in the central portion of the valley. The basalts are of probable Pliocene age and were erupted during a period of active extensional tectonics. Since their emplacement, the basalts have been extensively eroded and downfaulted. The present morphology reflects the erosional and depositional processes of prehistoric Lake Bonneville.

Twelve samples were analyzed chemically for major oxides, trace elements, and rare-earth elements. The basalts form a hypersthene normative series ranging from olivine …