Volcanology Commons^™

Exploration Of The Anaximander Mud Volcanoes, Timothy M. Shank, Santiago Herrera, Walter Cho, Christopher N. Roman, Katherine L. Croff Bell

Graduate School of Oceanography Faculty Publications

No abstract provided.

Crustal Assimilation And Magma Recharge In The Recent Mt. Etna Magma Plumbing System: Evidence From In Situ Plagioclase Textural And Compositional Data, Brad Pitcher

Undergraduate Honors Theses

Mt. Etna is Europe's largest and most active volcano, and as a result of its proximity to populated areas, understanding the structure of its magma plumbing system and the nature of its magmatic processes is essential for better predicting eruptive hazards. The aim of this study is to document core to rim textural, chemical, and isotopic variations in plagioclase, in order to investigate the structure of the subvolcanic magma system and the processes by which magmas change composition. Nomarski Differential Interference Contrast (NDIC) imaging was used to characterize the complex textures of plagioclase crystals in six trachybasaltic samples from eruption …

Volcanism And Astrobiology: Life On Earth And Beyond, Charles S. Cockell, Sherry L. Cady, Nicola Mcloughlin

Geology Faculty Publications and Presentations

Editorial Introduction to the 2011 Special Issue of Astrobiology.

Age And Petrogenesis Of The Roaring Mountain Rhyolites, Yellowstone Volcanic Field, Wyoming, Kathleen Marie Wooton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Extracaldera rhyolites in the Norris-Mammoth Corridor of the Yellowstone Volcanic Field (YVF) appear to be unrelated to intracaldera volcanism, resulting instead from a new crustal magma source derived from northeastward propagation of the Yellowstone “melting anomaly.” The youngest extracaldera rhyolite unit, the Roaring Mountain Member (RM), is chemically distinct from the previous extracaldera lavas, reverting to more primitive compositions.

This study suggests that the majority of the RM rhyolites erupted from the same large-scale silicic magma system. Based on geochemistry and 40Ar/39Ar geochronology, the Crystal Spring mingled rhyolite and Obsidian Cliff rhyolite erupted concurrently at 59.1 ± 2.0 ka. The …

Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan

Publications and Research

The Peay bentonites belong to the basal Frontier Formation (Bighorn Basin, north-central Wyoming), primarily outcrop in the Bighorn Basin, rest on an extensively bioturbated sandstone unit, the Peay Sandstone, and are generally the thinner bentonitic unit. Beds of very light gray to greenish gray bentonite are also abundant in the lower Frontier units between Kaycee and Mayoworth (Powder River Basin) and are very rarely as much as 3 m thick. Bentonite occurs within the interstratified shale, sandstone, and siltstone sequences of the lower Frontier unit throughout much of the southwestern Powder River Basin. The purpose of this study is to …

Petrogenesis Of The Greenwater Range: Comparison To The Crater Flat Volcanic Field And Implications For Hazard Assessment, Ashley Kaye Tibbetts

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pliocene basalts of the Greenwater Range, California erupted from 24 volcanic vents now represented by volcanic plugs, craters and scoria mounds. Basaltic magmas originated in the asthenospheric mantle, but show evidence of a lithospheric component. Depths and temperatures of melting calculated using a silica activity geobarometer are 54.3–89.6 km and 1367-1435oC, placing melting in the asthenosphere. The preferred petrogenetic model involves melting of lithospheric mantle thermally and mechanically, but not chemically, converted to asthenospheric mantle. Melting depths correspond to low velocity zones in the mantle as revealed in seismic profiles. Chemical and lithologic similarities between basalt in the Greenwater Range …

An Experimental Investigation Of Chemical Mass Transfer Processes In Crystallizing, Hydrous Silicate Magmas: The Genesis Of Ore Deposits And Metasomatic Fluids, Aaron S. Bell

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is comprised of three broadly related experimental petrology projects on phase equilibria and noble metal solubility in hydrous silicate melts. Chapters two and three combine experimental petrology with high precision laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis of experimental run products in order to quantitatively constrain the behavior of the investigated metals. Chapter four presents experimental evidence detailing a novel oxidation mechanism for degassing silicate liquids as well as exploring the geochemical consequences of the proposed mechanism.

Chapter two presents the results of an experimental study on Au, Pt, and Pd behavior in coexisting silicate melt-sulfide-oxide …

Yellowstone Super-Volcano: Evaluation, Potential Threats, And Possible Effects On Nebraska Citizens Health And Prosperity, Jennie Korgie

Department of Environmental Studies: Undergraduate Student Theses

Abstract Yellowstone National Park is located over a hot spot under the North American tectonic plate and holds a potentially explosive super-volcano that has the ability to cause deadly consequences on the North American continent. After an eruption the surrounding region would see the greatest devastation, covered by pyroclastic deposits and thick ash fall exterminating most all life and destroying all structures in its path. In landscapes of greater distance from the event the consequences will be less dramatic yet still substantial. Records of previous eruption data from the Yellowstone super-volcano show that the ash fall out from the eruption …

Lacustrine Sediment Record Of Multiple Quaternary Lava Dams On The Owyhee River, Southeastern Oregon, Caitlin Anne Orem

All Master's Theses

Multiple lava dams and correlating lakes impacted the Quaternary evolution of the Owyhee River. Sediment records from lava-dammed lakes were investigated to understand effects of the West Crater (WC) lava dam (~70 ka), the Saddle Butte 2 lava dam (~144 ka), and the Bogus Rim lava dam (~1.9 Ma). Evidence from the WC lava dam and related features indicates that dam duration consisted of five stages (1) dam and lake formation at ~70 ka; (2) dam overflow and lake sedimentation from ~70–46 ka; (3) removal of lava dam and lake termination from ~46 ka to at least 36 ka; (4) …