Geophysics and Seismology Commons^™

The Hera Orebody: A Complex Distal (Au–Zn–Pb–Ag–Cu) Skarn In The Cobar Basin Of Central New South Wales, Australia, Corey Wall

Geosciences Faculty Publications and Presentations

The Hera Au–Pb–Zn–Ag deposit in the southeastern Cobar Basin of central New South Wales preserves calc-silicate veins and remnant sandstone/carbonate-hosted skarn within a reduced anchizonal Siluro-Devonian turbidite sequence. The skarn orebody distribution is controlled by a long-lived, basin margin fault system, that has intersected a sedimentary horizon dominated by siliciclastic turbidite, with lesser gritstone and thick sandstone intervals, and rare carbonate-bearing stratigraphy. Foliation (S1) envelopes the orebody and is crosscut by a series of late-stage east–west and north–south trending faults. Skarn at Hera displays mineralogical zonation along strike, from southern spessartine–grossular–biotite–actinolite-rich associations, to central diopside-rich–zoisite–actinolite/tremolite–grossular-bearing associations, through to the northern …

Synchronous Emplacement Of The Anorthosite Xenolith-Bearing Beaver River Diabase And One Of The Largest Lava Flows On Earth, Yiming Zhang, Nicholas L. Swanson-Hysell, Mark D. Schmitz, James D. Miller, Margaret S. Avery

Geosciences Faculty Publications and Presentations

New geochronologic and paleomagnetic data from the North American Midcontinent Rift (MCR) reveal the synchronous emplacement of the Beaver River diabase, the anorthosite xenoliths within it, and the Greenstone Flow—one of the largest lava flows on Earth. A U-Pb zircon date of 1091.83 ± 0.21 Ma (2σ) from one of the anorthosite xenoliths is consistent with the anorthosite cumulate forming as part of the MCR and provides a maximum age constraint for the Beaver River diabase. Paired with the minimum age constraint of a cross-cutting Silver Bay intrusion (1091.61 ± 0.14 Ma; 2σ), these data tightly …

Prevention And Preparedness Of The Messina-Reggio Calabria Strait: An Earthquake Forecasting And Didactic Project, Francesco Di Stefano, Gioacchino Giampaolo Giuliani, Dimitar Ouzounov, Daniele Cataldi, Cristiano Fidani, Angelo D'Errico, Giulia Fioravanti

Mathematics, Physics, and Computer Science Faculty Articles and Research

This contribution is addressed to an introductive university course on the correlation existing between radon emission and earthquakes processes held following a flipped-class approach where students receive didactic materials prior to face-to-face lessons. This research was initially started to investigate the real correlation between Radon emission from the Earth and the occurrence of strong earthquakes by using measurements of hourly Radon flow variation. During quiet seismogenic conditions, we observe an unvarying level of Radon emission in the air. Before a strong earthquake, substantial variations of Radon (²²²Rn) concentration have been observed in the air, probably because of the …

Shallow Rupture Propagation Of Pleistocene Earthquakes Along The Hurricane Fault, Ut, Revealed By Hematite (U-Th)/He Thermochronometry And Textures, Madison P. Taylor, Alexis K. Ault, Margaret L. Odlum, Dennis L. Newell

Geoscience Faculty Publications

The material properties and distribution of faults above the seismogenic zone promote or inhibit earthquake rupture propagation. We document the depths and mechanics of fault slip along the seismically active Hurricane fault, UT, with scanning and transmission electron microscopy and hematite (U-Th)/He thermochronometry. Hematite occurs as mm-scale, striated patches on a >10 m2 thin, mirror-like silica fault surface. Hematite textures include bulbous aggregates and cataclasite, overlain by crystalline Fe-oxide nanorods and an amorphous silica layer at the slip interface. Textures reflect mechanical, fluid, and heat-assisted amorphization of hematite and silica-rich host rock that weaken the fault and promote rupture propagation. …

Trace Fossils, Algae, Invertebrate Remains And New U-Pb Detrital Zircon Geochronology From The Lower Cambrian Torneträsk Formation, Northern Sweden, Stephen Mcloughlin, Vivi Vajda, Timothy P. Topper, James L. Crowley, Fan Liu, Ove Johansson, Christian B. Skovsted

Geosciences Faculty Publications and Presentations

Nineteen ichnotaxa, together with algal and invertebrate remains, and various pseudo-traces and sedimentary structures are described from the Torneträsk Formation exposed near Lake Torneträsk, Lapland, Sweden, representing a marked increase in the diversity of biotic traces recorded from this unit. The “lower siltstone” interval of the Torneträsk Formation contains mostly simple pascichnia, fodinichnia and domichnia burrows and trails of low-energy shoreface to intertidal settings. The assemblage has very few forms characteristic of high-energy, soft-sediment, foreshore or upper shoreface environments (representative of the Skolithos ichnofacies).

Uranium-lead (U-Pb) LA-ICPMS analysis of zircon from a thin claystone layer within the “lower siltstone” interval …

Coupled Inversion Of Hydraulic And Self-Potential Data From Transient Outflow Experiments To Estimate Soil Petrophysical Properties, Jing Xie, Yian Cui, Qifei Niu

Geosciences Faculty Publications and Presentations

Hydraulicproperties of soils could play an important role in affecting the partitioning of precipitation in the critical zone. In addition to traditional approaches, in the last two decades, many geophysical methods have been used to aid the hydrologic characterization and measurement of geological materials. In particular, the self-potential (SP) method shows great potential in these hydrogeophysical applications. The objective of this study is to evaluate whether the addition of SP data can improve the estimation of hydraulic properties of soils in an outflow experiment. A stochastic, coupled hydrogeophysical inversion was developed, in which the governing equations were solved using the …

A Mélange Of Subduction Ages: Constraints On The Timescale Of Shear Zone Development And Underplating At The Subduction Interface, Catalina Schist (Ca, Usa), K. M. Harvey, S. Walker, P. G. Starr, S. C. Penniston-Dorland, M. J. Kohn, E. F. Baxter

Geosciences Faculty Publications and Presentations

The presence of mélange at the subduction interface influences numerous geochemical and geophysical processes. However, the relationship between the timescales of mélange development, deformation, and resultant mass transport is poorly understood. Here, we use Sm-Nd garnet geochronology to elucidate the timing of peak metamorphism for five garnet amphibolite tectonic blocks from the amphibolite-facies mélange zone of the Catalina Schist (Santa Catalina Island, CA). Ages range from 108 to 116 Ma and do not appear to correlate with the peak metamorphic temperature recorded by each block (between 640 and 740°C). The lack of correlation between age and peak temperature favors the …

(Re)Proposal Of Three Cambrian Subsystems And Their Geochronology, Ed Landing, Gerd Geyer, Mark D. Schmitz, Thomas Wotte, Artem Kouchinsky

Geosciences Faculty Publications and Presentations

The Cambrian is anomalous among geological systems as many reports divide it into three divisions of indeterminate rank. This use of “lower”, “middle”, and “upper” has been a convenient way to subdivide the Cambrian despite agreement it consists of four global series. Traditional divisions of the system into regional series (Lower, Middle, Upper) reflected local biotic developments not interprovincially correlatable with any precision. However, use of “lower”, “middle”, and “upper” is unsatisfactory. These adjectives lack standard definition, evoke the regional series, and are misused. Notably, there is an almost 50 year use of three Cambrian subsystems and a 1997 proposal …

Surface Morphology And Subsurface Ice Content Relationships In Arcadia Planitia, Mars And The Canadian High Arctic, Shannon M. Hibbard

Electronic Thesis and Dissertation Repository

As NASA and SpaceX prepare for future human missions to Mars as part of an In-situ Resource Utilization (ISRU) Space Act Agreement (SAA), we need more detailed characterization of ice at proposed landing sites to constrain ice accessibility, landing safety, and scientific value. Obtaining near-surface in situ water-ice can be used for rocket fuel and life support needs which would significantly reduce the mass needed for transport to and from Mars. Arcadia Planitia is the lowest-lying region in the northern hemisphere of Mars where abundant evidence exists for an ice-rich subsurface. Shallow Radar observations indicate a decameters-thick layer of water-ice …

Stochastic Source Modelling And Tsunami Analysis Of The 2012 Mw 7.8 Haida Gwaii Earthquake, Karina Martinez Alcala

Electronic Thesis and Dissertation Repository

The Mw 7.8 2012 Haida Gwaii Earthquake triggered a tsunami that highlighted the importance of tsunami hazard assessment on Canada’s Pacific coast. Stochastic source modelling serves as a valuable method to assess future tsunami hazard and has not been performed for this region. The source models characterize the uncertainty of earthquake ruptures by considering variability in fault geometry and slip heterogeneity, which, in turn, allows the consideration of a wide range of tsunami scenarios in the Haida Gwaii region. The model predictions are constrained by observational data and past source inversion studies. One hundred twenty-eight stochastic tsunami scenarios are generated …

A Transformer-Based Classification System For Volcanic Seismic Signals, Cristian Bravo Roman, Cindy Mora Stock, Alexander James Hemming

Undergraduate Student Research Internships Conference

Volcanic seismic signals are a key element in volcano monitoring to assess the state of unrest and a possible eruption style and timing. Different sources such as brittle fracture (volcano-tectonic - VT) or fluid movement (long period - LP) generate signals with distinct characteristics in frequency content and shape, but site effects such as attenuation or background noise make their determination difficult to the untrained eye. In cases of unrest or an eminent eruption, the amount of data would require a fast and reliable source of pre-classification to classify and catalogue to aid in the job usually done by a …

Evaluation Of Geohazards In The Cape Girardeau Area Using Lidar And Gis, Southeast Missouri, Usa, Olufeyisayo B. Ilesanmi, J. David Rogers, Francisca Oboh-Ikuenobe

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The New Madrid Seismic Zone (NMSZ) has historically recorded some of the largest intensity earthquakes in North America, including significant earth movements that resulted in about 2000 felt earthquakes during 1811-1812. The region continues to experience mass wasting due to earth movements. The aim of this study is to understand the influence of geologic variables on mass wasting processes in the greater Cape Girardeau area, which forms the commercial center of Missouri's fertile "Bootheel" region. Earth movement susceptibility was evaluated in Cape Girardeau and Bollinger counties and portions of Stoddard and Scott counties by mapping potential landslide features on topographic …

Stratigraphic Evidence Of Two Historical Tsunamis On The Semi-Arid Coast Of North-Central Chile, Jessica M. Depaolis, Tina Dura, Breanyn Macinnes, Lisa L. Ely, Marco Cisternas, Matías Carvajal, Hui Tang, Hermann M. Fritz, Cyntia Mizobe, Robert L. Wesson, Gino Figueroa, Nicole Brennan, Benjamin P. Horton, Jessica E. Pilarczyk, D. Reide Corbett, Benjamin C. Gill, Robert Weiss

Geological Sciences Faculty Scholarship

On September 16, 2015, a M_w 8.3 earthquake struck the north-central Chile coast, triggering a tsunami observed along 500 km of coastline, between Huasco (28.5°S) and San Antonio (33.5°S). This tsunami provided a unique opportunity to examine the nature of tsunami deposits in a semi-arid, siliciclastic environment where stratigraphic and sedimentological records of past tsunamis are difficult to distinguish. To improve our ability to identify such evidence, we targeted one of the few low-energy, organic-rich depositional environments in north-central Chile: Pachingo marsh in Tongoy Bay (30.3°S).

We found sedimentary evidence of the 2015 and one previous tsunami as tabular …

Void Hunting: Ambient Noise Tomography For Spatio-Temporal Subsurface Imaging And Monitoring In Karst Environments, John B. Paustian

Boise State University Theses and Dissertations

Karst environments are characterized by voids, i.e. sinkholes and conduits of varying size that arise from the active dissolution of carbonate rock by acidic groundwater. These voids, whether air-, water-, or soil-filled, can be difficult to image using near-surface geophysical methods due to the limited investigation depths of most active-source methods. In addition, due to the significant effort it takes to collect active-source data, investigators are often unable to monitor spatio-temporal variations in the subsurface. The ability to detect, image, and monitor subsurface voids improves the understanding of processes that create and transform voids, a vitally important insight across a …

Fundamental Resonant Frequencies Derived From Shallow Sediment Properties For The Charleston, South Carolina Area, William Dale Schermerhorn

Boise State University Theses and Dissertations

Large historic earthquakes, low velocity near surface sediments, a poor understanding of earthquake sources, and a growing population base for the Charleston, South Carolina area suggest robust site response and active fault maps are needed. A Boise State University team acquired 14 km of new surface-based seismic data to obtain surface wave dispersion curves and reflection images for the southern isoseismal region of the 1886 earthquake. From these data, I generate shear wave velocity (Vs)-depth profiles through a grid search approach. I integrate my results with other published data to develop a soil thickness and high frequency fundamental resonance maps …

Assessing Controls On Ice Dynamics At Crane Glacier, Antarctic Peninsula Using A Numerical Ice Flow Model, Rainey Aberle

Boise State University Theses and Dissertations

The widespread retreat of glaciers and the collapse of ice shelves along the Antarctic Peninsula has been attributed to atmospheric and oceanic warming, which promotes mass loss. However, several glaciers on the eastern peninsula that were buttressed by the Larsen A and B ice shelves prior to collapse in 1995 and 2002, respectively, have been advancing in recent years. This asymmetric pattern of rapid retreat and long-term re-advance is similar to the tidewater glacier cycle, which can occur largely independent of climate forcing. Here, I use a width- and depth-integrated numerical ice flow model to investigate glacier response to ice …

Laboratory Measurement Of Electrical And Hydraulic Properties Of Regolith Over Granitic Bedrock, Taylor James Bienvenue

Boise State University Theses and Dissertations

Characterizing water flux within the critical zone (CZ) is essential for a multitude of studies and applications related to irrigation, drainage, water management, and contaminant transport. Trying to measure water flux in the critical zone, specifically in the subsurface, is difficult due to the associated structural heterogeneity and complex interactions taking place between biological, chemical, and physical processes. Current methods (i.e., inferred from soil suction and soil moisture measurements) to characterize water flux within the critical zone can be time consuming and are not directly related to water flux. Recent literature has provided evidence that self-potential (SP) is a promising …

Dynamic Mass Loss From Greenland's Peripheral Glaciers, Katherine E. Bollen

Boise State University Theses and Dissertations

While global glacier mass balance has decreased rapidly over the last two decades, mass loss has been greatest in regions with marine-terminating glaciers. In Greenland, peripheral glaciers and ice caps (GICs) cover only ~5% of Greenland’s area but contributed ~14-20% of the island’s ice mass loss between 2003-2008. Although Greenland GIC’s mass loss due to surface meltwater runoff have been estimated using atmospheric models, mass loss due to changes in ice discharge into surrounding ocean basins (i.e., dynamic mass loss) remains unquantified. Here, we use the flux gate method to estimate discharge from Greenland’s 594 marine-terminating peripheral glaciers between 1985 …

Seismic Imaging Of Active And Ancient Co2 Pathways In The Little Grand Wash Fault, Jonathan Yelton

Boise State University Theses and Dissertations

Understanding the migration behavior of carbon dioxide (CO2) during long-term geological storage is crucial to the success of carbon capture and sequestration technology. I explore p-wave and s-wave seismic properties across the Little Grand Wash fault in east-central Utah, a natural CO2 seep and analogue for a long-failed sequestration site. Travertines dated to at least 113,000 k.y. and geochemical surveys confirm both modern and ancient CO2 leakage along the fault. Outgassing is currently focused in damage zones where the total fluid pressure may reduce the minimum horizontal effective stress. Regional stress changes may be responsible for decadal- to millennial-scale changes …

An Integrative Approach For Environmental Assessment And Water Resources Management Using Direct Current Resistivity (Dc), Geographic Information System (Gis), Remote Sensing, And Gain And Loss Method, Dina Ragab Desouki Abdelmoneim

Boise State University Theses and Dissertations

Sustainable water resource management is a crucial national and global issue (Currell et al., 2012). In arid areas, groundwater is often the major source of water or at least a crucial supplement to other freshwater resources for agriculture, industry and domestic consumption (Vrba and Renaud, 2016). The complexity associated with groundwater-surface water interactions creates uncertainty about water resource sustainability in semi-arid environments, especially with urbanization and population growth. Flood irrigation in the early 1900s increased the shallow groundwater table in the Treasure Valley (TV), but with increasing irrigation efficiencies, they have been declining since the 1960s with a mean decline …