A5114377224- Geological and Geochemical Analysis
- Geochemistry and Geologic Mapping
- Paleontology and Stratigraphy of Fossils
- earthquake and tectonic studies
- Geological and Geophysical Studies
- High-pressure geophysics and materials
University of Geneva
2013-2017
Marine carbonates are archives of geochemical proxies, such as e.g. Sr and U-Pb isotopes, which potentially can be utilized in the reconstruction past climate conditions, ancient seawater composition and/or their alteration during burial fluid interaction, if interpreted accurately. The ability to confidently reconstruct environmental conditions times is great importance since they linked with changes biosphere. For example, Ediacaran-Cambrian transition was a period where significant...
     The late Ediacaran Nama Group of southern Namibia and northwestern South Africa hosts a mixed carbonate-siliciclastic Proterozoic succession is key for resolving the timing early metazoan evolution, leading to suite geochronology studies these rocks. Important outcrops upper are found in Swartpunt area, where depositional sequence preserved as series thrust plates that formed during compression associated with Gariep orogeny. Here, numerous silicified...
Abstract. The highest precision and accuracy in U–Pb geochronology is achieved using isotope dilution thermal ionisation mass spectrometry (ID-TIMS), a technique which owes its reliability to precise Pb U ratio analysis, largely unified framework of lab protocols, common isotopic tracers with accurately determined compositions. However, while hardware protocol developments have steadily improved the analytical precision, level ID-TIMS dates from different laboratories agree remains...
Field, geochemical, and geochronologic data of high-grade basement metamafic evolved rocks are used to identify the nature timing pre-Alpine crustal growth Rhodope Massif. These occur intrusive into clastic-carbonate metasedimentary succession. Petrography mineral chemistry show compositions consistent with Alpine amphibolite-facies metamorphism that obliterated original igneous textures protoliths. Bulk-rock geochemistry identifies low-Ti tholeiitic calc-alkaline gabbroic-basaltic...
[Lehrmann et al. (2006)][1] recently interpolated a new age of 247.2 Ma for the Early-Middle Triassic boundary in Guandao (Guizhou Province, south China) where four U-Pb ages were measured from ash layers bracketing this as defined by conodonts. Along with previous data