THE SOURCE OF THE ESPINHAÇO DIAMONDS: EVIDENCES FROM SHRIMP U-PB ZIRCON AGES OF THE SOPA CONGLOMERATE AND PB-PB ZIRCON EVAPORATION AGES OF METAVOLCANIC ROCKS

U/Pb and Pb/Pb zircon ages from granitoid rocks of Wallagga area: constraints on magmatic and tectonic evolution of Precambrian rocks of western Ethiopia

The Precambrian rocks in western Ethiopia consist of highand low-grade terranes intruded by granitoids with a wide compositional spectrum. The formation ages of these granitoid rocks are, so far, poorly understood. Single-grain zircon Pb/Pb evaporation and conventional U/Pb dating conducted on four granitoids places time constraints on their emplacement and tectonothermal events. Three granitoi...

U-Pb Zircon Ages and Pb Isotope Geochemistry of Gold Deposits in the Carolina Slate Belt of South Carolina

U=Pb zircon ages constrain the architecture of the ultrahigh-pressure Qinling–Dabie Orogen, China

New SHRIMP and TIMS zircon ages, Ar=Ar ages, and eclogite locations contribute significantly to our understanding of the ultrahigh-pressure Dabie Shan. (1) The geographic extent of the Yangtze craton that was subducted to ultrahigh pressure extends to the northern edge of the Dabie Shan. (2) The northern half of the Dabie Shan is a magmatic complex, intruded over a 10-Myr interval between 137 a...

U-Pb ages of angrites

The chemistry and isotope chemistry of natural materials is highly indicative of provenance and process throughout geological history. Our studies range in time from the earliest solar system through to processes that are actively taking place today, and in scope from planetary systems to individual molecules. Active areas of research centre on planetary studies, metamorphic and igneous geochem...

U–Pb zircon ages as a sediment mixing tracer in the Nepal Himalaya

This paper presents a new approach to quantify sediment mixing based on the mixing of U–Pb zircon age distributions within sediment. Two statistical techniques are presented to determine the proportion in which two known age distributions combine to create a known mixed age distribution. These techniques are then used to determine relative erosion rates between adjacent drainage basins above an...