A5029549010- Geological and Geochemical Analysis
- Geology and Paleoclimatology Research
- earthquake and tectonic studies
- High-pressure geophysics and materials
- Geochemistry and Geologic Mapping
- Geological and Geophysical Studies
- Geological Studies and Exploration
- Geological formations and processes
- Geomagnetism and Paleomagnetism Studies
- Geological and Geophysical Studies Worldwide
- Pleistocene-Era Hominins and Archaeology
- Archaeology and ancient environmental studies
- Methane Hydrates and Related Phenomena
- Paleontology and Stratigraphy of Fossils
- Geological Formations and Processes Exploration
- Hydrocarbon exploration and reservoir analysis
- Astro and Planetary Science
- Landslides and related hazards
- Evolution and Paleontology Studies
- Marine and environmental studies
- Isotope Analysis in Ecology
- Maritime and Coastal Archaeology
- Planetary Science and Exploration
- Archaeological and Geological Studies
- Geochemistry and Geochronology of Asian Mineral Deposits
Vrije Universiteit Amsterdam
2015-2024
Amsterdam UMC Location VUmc
2012-2021
GGD Amsterdam
2006-2020
Freie Universität Berlin
2019
University of Amsterdam
1997-2017
Institute of Geochemistry
1995-2016
Berkeley Geochronology Center
2008
Planetary Science Institute
2007-2008
University of California, Berkeley
2008
Universidad de Salamanca
2007
Calibration of the geological time scale is achieved by independent radioisotopic and astronomical dating, but these techniques yield discrepancies approximately 1.0% or more, limiting our ability to reconstruct Earth history. To overcome this fundamental setback, we compared 40Ar/39Ar ages tephras in marine deposits Morocco calibrate age Fish Canyon sanidine, most widely used standard geochronology. This calibration results a more precise older 28.201 +/- 0.046 million years ago (Ma)...
Abstract The 40Ar/39Ar dating method is among the most versatile of geochronometers, having potential to date a broad variety K-bearing materials spanning from time Earth’s formation into historical realm. Measurements using modern noble-gas mass spectrometers are now producing dates with analytical uncertainties ∼0.1%, thereby providing precise constraints for wide range geologic and extraterrestrial processes. Analyses increasingly smaller subsamples have revealed age dispersion in many...
South Pacific intraplate volcanoes have been active since the Early Cretaceous. Their HIMU‐EMI‐EMII mantle sources can be traced back into West Seamount Province (WPSP) using plate tectonic reconstructions, implying that these distinctive components are enduring features within Earth's for, at least, last 120 Myr. These correlations eminent on scale of WPSP and Thermal Isotopic Anomaly (SOPITA), but evolution single hot spots emerges notably more complicated. Hot in SOPITA regions typically...
Abstract 40 Ar/ 39 Ar age spectrum analysis of phengite separates from Naxos, part the Attic Cycladic Metamorphic Belt in Greece, indicates that cooling following high‐pressure, low‐ to medium‐temperature metamorphism, M 1 , occurred about 50 Ma ago. Phengite has Ar* gradients suggest scatter observed conventional K–Ar ages was caused by diffusion radiogenic argon minerals during a younger 2 . In central this metamorphism ( ) overprinted original mineral assemblages completely, and is...
Estimates of the relative motion between Hawaiian and Louisville hot spots have consequences for understanding role character deep Pacific‐mantle return flow. The these primary can be inferred by comparing age records their seamount trails. We report 40 Ar/ 39 Ar ages 18 lavas from 10 seamounts along Hawaiian‐Emperor Seamount Chain (HESC), showing that volcanism started in sharp portion Bend (HEB) at ≥47.5 Ma continued ≥5 Myr. slope along‐track distance currently active spot plotted versus...
The eastern termination of the Himalayan orogen forms a structural syntaxis that is characterised by young (from 10 to < 1 Ma) mineral growth and cooling ages document Late Miocene Pleistocene structural, metamorphic, igneous exhumation events. This region steep antiformal in part domal structure folds suture zone between Indian Asian plates. It dissected Yarlung Tsangpo, one major rivers Himalayan–Tibet region, which becomes Brahmaputra River foreland basin before emptying into Bay Bengal....
Geochemical and chronological data for Cenozoic plutons dikes from northern Victoria Land (Antarctica), were used to propose a tectonic‐magmatic model this portion of the West Antarctic Rift System (WARS). The seven major are compositionally bimodal, with gabbroic syenitic portions. Among 180 studied dikes, most 1 m thick have alkali basalt‐basanite‐tephrite compositions, along minor intermediate rocks. Trachytic‐rhyolitic (up 50 thick) by far less common. 40 Ar‐ 39 Ar indicate middle Eocene...
Zircon U‐Th‐Pb and mineral K‐Ar 40Ar/39Ar isotopic studies indicate that the maximum deposition age of Mt Narryer quartzite (which contains detrital zircons up to 4200 Ma old) is 3280 Ma, or by association with other sequences possibly 3100 Ma. This postdates a major episode high‐grade metamorphism, granite emplacement deformation at 3300 which affected adjacent gneiss terranes previously had been considered have metasediments basement gneisses alike. Prograde metamorphism amphibolite facies...
Research Article| June 01, 1997 Laser 40Ar/39Ar dating of single detrital muscovite grains from early foreland-basin sedimentary deposits in India: Implications for Himalayan evolution Y. M. R. Najman; Najman 1Department Geology and Geophysics, Edinburgh University, West Mains Road, EH9 3JW, United Kingdom2Department Earth Sciences, Cambridge Downing Street, CB2 3EQ, Kingdom Search other works by this author on: GSW Google Scholar S. Pringle; Pringle 3Scottish Universities Reactor Centre,...
A multi-method geochronological approach is applied to unravel the dynamics of a paired metamorphic belt in Coastal Cordillera central Chile. This represented by high-pressure–low-temperature rocks an accretionary prism (Western Series), and low-pressure–high-temperature overprint retro-wedge with less deformed metagreywackes (Eastern Series) intruded magmas coeval arc. pervasive transposition foliation formed interlayered oceanic crust Western Series during basal accretion near peak...