Publications
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Eruptive history of northern Harrat Rahat—Volume, timing, and composition of volcanism over the past 1.2 million years
Harrat Rahat, one of several large, basalt-dominated volcanic fields in the western part of the Kingdom of Saudi Arabia, is a prime example of continental, intraplate volcanism. Excellent exposure makes this an outstanding site to investigate changing volcanic flux and composition through time. We present 93 40Ar/39Ar ages and 6 36Cl surface-exposure ages for volcanic deposits throughout northern
Authors
Mark E. Stelten, Drew T. Downs, Duane E. Champion, Hannah R. Dietterich, Andrew T. Calvert, Thomas W. Sisson, Gail A. Mahood, Hani M. Zahran
Eruptive history within the vicinity of Al Madīnah in northern Harrat Rahat, Kingdom of Saudi Arabia
The northernmost part of the Harrat Rahat volcanic field contains early Pleistocene to Holocene mafic eruptive products within the vicinity of the city of Al Madīnah, Kingdom of Saudi Arabia. A detailed geologic investigation into the eruptive history of a 570 square kilometer (km2) area covering Al Madīnah and the surrounding area has yielded 33 mapped Quaternary volcanic units consisting of lava
Authors
Drew T. Downs, Mark E. Stelten, Duane E. Champion, Hannah R. Dietterich, Khalid Hassan, Jamal Shawali
Cenozoic tectonics of the western Arabia Plate related to harrat magmatism near Al Madīnah, Kingdom of Saudi Arabia
Sprawling volcanic fields, or harrats, in western Saudi Arabia have been emplaced during the past 30 million years following effusions of flood basalts in Ethiopia and Yemen. Although broadly associated with volcanism in three rift valleys (Red Sea, Gulf of Aden, and East African Rift Zone) radiating from the Afar depression, harrat abundance on the Arabian Peninsula indicates that volcanism is di
Authors
Andrew T. Calvert, Thomas W. Sisson
The Saudi Geological Survey-U.S. Geological Survey northern Harrat Rahat project—Styles, rates, causes, and hazards of volcanism near Al Madīnah al Munawwarah, Kingdom of Saudi Arabia
Active volcanic systems pose serious hazards to people and property including inundation and incineration by lava, blanketing by tephra (volcanic ash), exposure to noxious volcanic gases, and damage from shallow earthquakes triggered by ascending molten material (magma). To improve understanding of volcanism and associated seismicity on the western Arabia Plate, the Saudi Geological Survey and the
Authors
Thomas W. Sisson, Andrew T. Calvert, Walter D. Mooney
Active volcanism on the Arabian Shield—Geology, volcanology, and geophysics of northern Harrat Rahat and vicinity, Kingdom of Saudi Arabia
Active volcanic systems pose serious hazards to people and property including inundation and incineration by lava, blanketing by tephra (volcanic ash), exposure to noxious volcanic gases, and damage from shallow earthquakes triggered by ascending molten material (magma). To improve understanding of volcanism and associated seismicity on the western Arabia Plate, the Saudi Geological Survey and the
Dynamics of magma mixing and magma mobilization beneath Mauna Loa – Insights from the 1950 AD Southwest Rift Zone eruption.
Eruptions from Mauna Loa’s Southwest Rift Zone (SWRZ) pose a significant threat to nearby communities due to high eruption rates and steep slopes resulting in little time for evacuation. Despite the large body of research done on Mauna Loa, knowledge of the timing and duration of magma residence and transfer through its internal plumbing system is still poorly constrained. This study presents a fi
Authors
Maren Kahl, Daniel J. Morgan, Carl Thornber, Richard Walshaw, Kendra J. Lynn, Frank A. Trusdell
Editorial: Remote sensing of volcanic gas emissions from the ground, air, and space
When magma rises in volcanic systems, volatile species exsolve from the melt and are outgassed to the atmosphere. The melt composition and temperature, depth at which degassing occurs, extent of gas-water-rock interactions, and volume of ascending magma are all factors that determine the composition and rate of gas emissions at the surface. Interpreted in a petrological framework, gas measurements
Authors
Christoph Kern, Santiago Arellano, Robin Campion, Silvana Hidalgo, Ryunosuke Kazahaya
Understanding the drivers of volcano deformation through geodetic model verification and validation
Volcano geodesy often involves the use of models to explain observed surface deformation. A variety of forward models are used, from analytical point sources to numerical simulations that consider complex magma system geometries, topography, and material properties. Various inversion methods can then be used to relate observed volcano data to models. Ideally, forward models should be verified thro
Authors
Joshua Allen Crozier, Leif Karlstrom, Emily Montgomery-Brown, Mario Angarita, Valérie Cayol, Mary Grace Bato, Taiyi Wang, Ronni Grapenthin, Tara Shreve, Kyle R. Anderson, Ana Astort, Olivier Bodart, Flavio Cannavò, Gilda Currenti, Farshid Dabaghi, Brittany A. Erickson, Deepak Garg, Matthew Head, Adriana Iozzia, Young Cheol Kim, Hélène Le Mével, Camila Novoa Lizama, Cody Rucker, Francesca Silverii, Yan Zhan
Chemistry and petrography of early 19th century basaltic andesites and basalts from the Kamakaiʻa Hills in the Southwest Rift Zone of Kīlauea volcano, Hawaiʻi
Kīlauea is a frequently active, open-system volcano on the Island of Hawaiʻi known for erupting olivine-dominated tholeiitic basalt compositions. On rare occasions it erupts more differentiated magmas (<1% of erupted volume), such as basaltic andesites and andesites, from its rift zones. These differentiated magmas offer an opportunity to understand better the petrology, magma storage, magma mixin
Authors
Drew T. Downs, May Sas, Richard W. Hazlett
Creating oriented and precisely sectioned mineral mounts for in situ chemical analyses—An example using olivine for diffusion chronometry studies
Diffusion chronometry is now a widely applied methodology for determining the rates and timescales of geologic processes from the chemical zoning observed in minerals. Despite the popularity of the method, several challenges still remain during its application, including: (1) the random sectioning of minerals either in thin sections or grain mounts in which both off-center and oblique sections con
Authors
Kendra J. Lynn, Liliana G. Desmither
Probabilistic source classification of large tephra producing eruptions using supervised machine learning: An example from the Alaska-Aleutian arc
Alaska contains over 130 volcanoes and volcanic fields that have been active within the last 2 million years. Of these, roughly 90 have erupted during the Holocene, with many characterized by at least one large explosive eruption. These large tephra-producing eruptions (LTPEs) generate orders of magnitude more erupted material than a “typical” arc explosive eruption and distribute ash thousands of
Authors
Jordan Edward Lubbers, Matthew W. Loewen, Kristi L. Wallace, Michelle L. Coombs, Jason A. Addison
The dynamic influence of subsurface geological processes on the assembly and diversification of thermophilic microbial communities in continental hydrothermal systems
An accepted paradigm of hydrothermal systems is the process of phase separation, or boiling, of a deep, homogeneous hydrothermal fluid as it ascends through the subsurface resulting in gas rich and gas poor fluids. While phase separation helps to explain first-order patterns in the chemistry and biology of a hot spring’s surficial expression, we know little about the subsurface architecture beneat
Authors
Kenneth W.W. Sims, Cole M. Messa, Sean R Scott, Andrew D Parsekian, Andrew Miller, Abraham L. Role, Timothy P. Moloney, Everett L. Shock, Jacob B. Lowenstern, R. Blaine McCleskey, Matthew A. Charette, Bradley Carr, Sylvain Pasquet, Henry Heasler, Cheryl Jaworowski, W. Steven Holbrook, Melody R. Lindsay, Daniel R. Colman, Eric S. Boyd