A5085114232- Geological and Geochemical Analysis
- earthquake and tectonic studies
- High-pressure geophysics and materials
- Geology and Paleoclimatology Research
- Methane Hydrates and Related Phenomena
- Geochemistry and Geologic Mapping
- Geophysics and Gravity Measurements
- Geological and Geophysical Studies
- Spacecraft and Cryogenic Technologies
- Offshore Engineering and Technologies
- Hydrocarbon exploration and reservoir analysis
- Geomagnetism and Paleomagnetism Studies
- Paleontology and Stratigraphy of Fossils
- Astro and Planetary Science
- Geochemistry and Elemental Analysis
- Astronomical Observations and Instrumentation
- Geological and Tectonic Studies in Latin America
- Geological Studies and Exploration
- Reservoir Engineering and Simulation Methods
- Drilling and Well Engineering
- Scientific Research and Discoveries
- Astronomy and Astrophysical Research
- Geological Modeling and Analysis
- Inertial Sensor and Navigation
- Seismic Imaging and Inversion Techniques
University of California, Santa Cruz
2014-2024
University of Technology Malaysia
2015-2017
Office of Chief Medical Examiner
2017
International Ocean Discovery Program
2015
Sorbonne Université
1984-2014
Pacific Northwest National Laboratory
2014
Rutgers, The State University of New Jersey
2014
Laboratoire de Météorologie Dynamique
2014
Centre National de la Recherche Scientifique
2014
Monterey Bay Aquarium Research Institute
2012
In order to better constrain the paleogeographic evolution of south China we measured Sm‐Nd and Rb‐Sr isotopic compositions for 23 Mesozoic granites that crop out throughout area. Tightly grouped neodymium depleted mantle model ages (1.4 ± 0.3 Ga) suggest region is underlain by relatively homogeneous Proterozoic crust fail define crustal provinces. Neither nor geologic data a suture exists. However, possessing anomalously high Sm (>8 ppm) Nd (>45 concentrations, initial epsilon (−4...
The Tongan Islands comprise a double island chain, and lie at the northern end of an active arc extending NNE from New Zealand. eastern chain are limestone covered, with underlying pre-Upper Eocene gabbro-basalt-andesite series exposed on one island. volcanoes, subject this paper, form western some 100 km above westward dipping seismic zone. Basaltic andesite dominates islands Hunga Ha'apai Late (and also Tofua Kao, which not described in paper). Dacite is main lava Fonualei 1967–68 Metis...
Turrialba volcano, the southeasternmost volcano in Central American arc, is constructed of medium to high‐K calcalkaline basalts, andesites, and dacites, plus rare basalts with unusually high Nb concentrations. The compositions these high‐Nb are more similar those intraplate than they typical or arc‐tholeiitic basalts. association arc front volcanoes, seemingly being restricted volcanoes that overlie Oligocene younger subducting crust edges plates. at have generally major element, trace...
Research Article| October 01, 1976 Composition and age of Lau Basin Ridge volcanic rocks: Implications for evolution an interarc basin remnant arc JAMES B. GILL 1Earth Sciences Board Center South Pacific Studies, University California, Santa Cruz, California 95064, School Earth Sciences, Australian National University, Canberra, ACT, Australia Search other works by this author on: GSW Google Scholar GSA Bulletin (1976) 87 (10): 1384–1395....
We present a concerted international effort to cross‐calibrate five synthetic Th isotope reference materials (UCSC “A”, OU “U”, WUN, IRMM‐35 and IRMM‐36), six rock TML, Icelandic ATHO, USGS BCR‐2, W‐2, BHVO‐2, LV18) using multi‐collector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS). then compare our new values with compilation of literature mass spectrometric data for these derive recommended “consensus” 230 Th/ 232 each. also dilution U concentration four W‐2).
Across‐arc geochemical trends can constrain subduction zone dynamics by providing clues to the source composition and melting systematics of subduction‐related magmas over a wide portion mantle wedge. The Izu‐Bonin arc contains an active volcanic front, extensional zone, series 3–9 Ma southwest trending acrossarc seamount chains. front (VF) one most depleted suites any arc, with basalt containing 0.2–0.7 ppm Nb, 25–50 Zr, Nb/Zr < 0.015, Zr/Y 2.5. Ratios concentrations mantle‐derived...
The chemical composition of mid-ocean ridge basalt, the most prevalent magma type on planet, reflects melt's continuous reequilibration with surrounding mantle during porous flow. Models basalt extraction that account for observed uranium-series disequilibria Juan de Fuca constrain both abundance melt beneath ridges (0.1 to 0.2 percent) and style melting. Unlike models incorporate near-fractional melts (dynamic melting), mixing equilibrium flow derived from heterogeneous source materials...
Shoshonitic volcanism began in Fiji within 50 km of and 0.5 m.y. after formation a transverse rift which broke the oceanic Vitiaz Arc across strike. basalts erupted from 10 volcanoes along three lineaments for up to 225 away strike, 5.5 3.0 Ma, during Fiji's “incipient rifting stage.” Three shoshonitic suites are distinguished based on differentiation‐normalized alkali contents, but K‐Rb‐Ba‐Sr, P‐rare earth element (REE), Ti‐Zr‐Hf enrichments occur independent each other. Enrichments...
Abundant rhyolite has erupted from the Izu–Bonin–Mariana volcanic arc (IBM arc) its earliest stage (Eocene) to present. Geochemically, three types of Quaternary rhyolites exist in Izu–Bonin front, and they are closely related volcano type crustal structure. The dominantly basaltic islands front produce small volumes that we call R1. submarine calderas erupt mostly R2. Seamounts, knolls, pillow ridges backarc extensional zone but also contain R3. thickest total crust, intermediate composition...