Search Results - "Jicha, Brian"

Re-evaluation of the ages of 40Ar/39Ar sanidine standards and supereruptions in the western U.S. using a Noblesse multi-collector mass spectrometer by Jicha, Brian R., Singer, Brad S., Sobol, Peter

“…The rewards from resolving the tempo of magmatic, paleobiologic, paleoclimatic, and tectonic processes at better than the per mil level of precision have…”
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A new tephrochronology for early diverse stone tool technologies and long-distance raw material transport in the Middle to Late Pleistocene Kapthurin Formation, East Africa by Blegen, Nick, Jicha, Brian R., McBrearty, Sally

“…The Middle to Late Pleistocene (780–10 ka) of East Africa records evidence of significant behavioral change, early fossils of Homo sapiens, and the dispersals…”
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The Impact of Slab Rollback on Earth's Surface: Uplift and Extension in the Hinterland of the North American Cordillera by Cassel, Elizabeth J., Smith, M. Elliot, Jicha, Brian R.

“…Slab rollback processes alter the intraplate force balance and buoyancy of the overriding plate, driving surface uplift or extension. From ca. 55–24 Ma,…”
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Incremental heating of Bishop Tuff sanidine reveals preeruptive radiogenic Ar and rapid remobilization from cold storage by Andersen, Nathan L., Jicha, Brian R., Singer, Brad S., Hildreth, Wes

“…Accurate and precise ages of large silicic eruptions are critical to calibrating the geologic timescale and gauging the tempo of changes in climate, biologic…”
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The hottest lavas of the Phanerozoic and the survival of deep Archaean reservoirs by Trela, Jarek, Gazel, Esteban, Sobolev, Alexander V., Moore, Lowell, Bizimis, Michael, Jicha, Brian, Batanova, Valentina G.

“…Large igneous provinces and some hotspot volcanoes are thought to form above thermochemical anomalies known as mantle plumes. Petrologic investigations that…”
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Reexamining the Honolulu Volcanics: Hawai'i's Classic Case of Rejuvenation Volcanism by Garcia, Michael O, Norman, Marc D, Jicha, Brian R, Lynn, Kendra J, Jiang, Peng

“…Abstract Rejuvenated volcanism is a worldwide phenomenon occurring on many oceanic islands in all of the major ocean basins. This plume-related volcanism…”
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100 Ma sweat bee nests: Early and rapid co-diversification of crown bees and flowering plants by Genise, Jorge Fernando, Bellosi, Eduardo S, Sarzetti, Laura C, Krause, J Marcelo, Dinghi, Pablo A, Sánchez, M Victoria, Umazano, A Martín, Puerta, Pablo, Cantil, Liliana F, Jicha, Brian R

“…100 Ma sweat bee nests reported herein are the oldest evidence of crown bees. A new phylogeny for short-tongued bees, calibrated with these nests dated with…”
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40Ar/39Ar dating of Glacial Termination VI: constraints on the duration of Marine Isotopic Stage 13 by Marra, Fabrizio, Florindo, Fabio, Jicha, Brian R.

“…We present four new 40 Ar/ 39 Ar ages of tephra layers from an aggradational succession (Valle Giulia Formation) near the mouth of the Tiber Valley in Rome…”
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Initial Characterisation of SK01 Sanidine: A Candidate 40Ar/39Ar Reference Material by Li, Youjuan, Jicha, Brian R., Zhang, Wanfeng, Chen, Wen, Singer, Brad S., Zheng, Dewen, He, Huaiyu

“…The precision and accuracy of 40Ar/39Ar dates are ultimately linked to co‐irradiated reference materials of known age. Here we provide new data from the SK01…”
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Building Arc Crust: Plutonic to Volcanic Connections in an Extensional Oceanic Arc, the Southern Alisitos Arc, Baja California by Morris, Rebecca A, DeBari, Susan M, Busby, Cathy, Medynski, Sarah, Jicha, Brian R

“…Abstract The ∼50 km long Rosario segment of the Cretaceous Alisitos oceanic arc terrane provides undeformed three-dimensional exposures of the upper 7 km of an…”
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Record of massive upwellings from the Pacific large low shear velocity province by Madrigal, Pilar, Gazel, Esteban, Flores, Kennet E., Bizimis, Michael, Jicha, Brian

“…Large igneous provinces, as the surface expression of deep mantle processes, play a key role in the evolution of the planet. Here we analyse the geochemical…”
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Australasian impact crater buried under the Bolaven volcanic field, Southern Laos by Sieh, Kerry, Herrin, Jason, Jicha, Brian, Angel, Dayana Schonwalder, Moore, James D. P., Banerjee, Paramesh, Wiwegwin, Weerachat, Sihavong, Vanpheng, Singer, Brad, Chualaowanich, Tawachai, Charusiri, Punya

“…The crater and proximal effects of the largest known young meteorite impact on Earth have eluded discovery for nearly a century. We present 4 lines of evidence…”
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The Calc-Alkaline Hidden Bay and Kagalaska Plutons and the Construction of the Central Aleutian Oceanic Arc Crust by Kay, Suzanne Mahlburg, Jicha, Brian R, Citron, Gary L, Kay, Robert W, Tibbetts, Ashley K, Rivera, Tiffany A

“…Abstract Calc-alkaline plutons are the major crustal building blocks of continental margins, but are rarely exposed in oceanic island arcs. Two of the best…”
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The Role of Water in Generating the Calc-alkaline Trend: New Volatile Data for Aleutian Magmas and a New Tholeiitic Index by Zimmer, Mindy M., Plank, Terry, Hauri, Erik H., Yogodzinski, Gene M., Stelling, Peter, Larsen, Jessica, Singer, Brad, Jicha, Brian, Mandeville, Charles, Nye, Christopher J.

“…The origin of tholeiitic (TH) versus calc-alkaline (CA) magmatic trends has long been debated. Part of the problem stems from the lack of a quantitative…”
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Predict: Assessing the Seismic Response in the city of Rome, Part 1. New Data for a Geologic Overview by Marra, Fabrizio, Rosa, Carlo, Silvestri, Daniele, Bordoni, Paola, Bulian, Francesca, Florindo, Fabio, Jicha, Brian, Cara, Fabrizio, Famiani, Daniela, Salvini, Riccardo

“…This work presents the preliminary results of the stratigraphic, paleomagnetic, micropaleontologic and geochronologic investigations carried out on the cores…”
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Petrogenesis of Pleistocene Basalts from the Western Snake River Plain, Idaho by Rivera, Tiffany A, White, Craig M, Schmitz, Mark D, Jicha, Brian R

“…Abstract We present new geochemical, Sr, Nd, and Pb isotope, and 40Ar/39Ar data from Pleistocene basalts of the Western Snake River Plain (WSRP), Idaho, USA to…”
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Facies architecture and time stratigraphic relationships of a confined trunk-tributary valley fill and unconfined fluvial system in the backwater of the Turonian Ferron-Notom Delta, Utah, U.S.A by Kynaston, David, Bhattacharya, Janok P., Singer, Brad S., Jicha, Brian R.

“…ABSTRACT This paper documents a tidally incised, mudstone-prone tributary valley fill linked to a trunk valley in the backwater limit of the Turonian Notom…”
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Synchronizing volcanic, sedimentary, and ice core records of Earth's last magnetic polarity reversal by Singer, Brad S, Jicha, Brian R, Mochizuki, Nobutatsu, Coe, Robert S

“…Reversal of Earth's magnetic field polarity every 10 to 10 years is among the most far-reaching, yet enigmatic, geophysical phenomena. The short duration of…”
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Long‐Lived Source Heterogeneities in the Galapagos Mantle Plume by Esteban Gazel, Jarek Trela, Michael Bizimis, Alexander Sobolev, Valentina Batanova, Cornelia Class, Brian Jicha

“…Abstract Mantle plume‐derived melts provide a unique glimpse into the chemical heterogeneity of the deep mantle. However, the exact processes involved in…”
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A melt-focusing zone in the lithospheric mantle preserved in the Santa Elena Ophiolite, Costa Rica by Madrigal, Pilar, Gazel, Esteban, Denyer, Percy, Smith, Ian, Jicha, Brian, Flores, Kennet E., Coleman, Drew, Snow, Jonathan

“…The Santa Elena Ophiolite in Costa Rica is composed of a well-preserved fragment of the lithospheric mantle that formed along a paleo-spreading center. Within…”
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