U-Pb age of the Diana Complex and Adirondack granulite petrogenesis

Zircon U-Pb geochronology of the Ottawan Orogeny, Adirondack Highlands, New York: regional and tectonic implications

Both single and multigrain U-Pb zircon thermal ionization mass spectrometry (TIMS) as well as sensitive high resolution ion microprobe (SHRIMP ll) dating of two suites of Adirondack granites have yielded ages constraining the principal tectonomagmatic events of the Ottawan Orogeny to the interval ca 1090–1035 Ma. The earliest of these consists of mildly A-type hornblende granites of the Hawkeye...

U-Pb AGE OF THE UNGROUPED ACHONDRITE NWA 8486

sr-nd isotopic characteristic, u-pb zircon geochronology, and petrogenesis of najmabad granodiorite batholith, eastern iran

the study area is located south of ghonabad in eastern iran. this area is situated between two major faults, darouneh to the north and dashtbyaz to the south. the movements of these faults cased major dislocation of this block. najmabad granodiorite to granite batholith is elongated trending east-west 2×8 km2. mineralization is associated with granite and monzonite. alteration zones are: propyl...

U-Pb and Pb-Pb age constraints on Paleoproterozoic magmatism, deformation and gold mineralization in the Omai area, Guyana Shield

The Omai intrusion-centred Au-quartz vein system, the largest Au producer presently operating in the Guyana Shield, was sampled for detailed U-Pb and Pb-Pb geochronology and petrological investigation. The age of a metavolcanic/sub-volcanic unit in the host rock sequence is 212092 Ma. Zircon analyses from the main body dioritic rocks give U-Pb ages of 209496, 2092911 and 2096+11/−10 Ma. Magmati...

petrogenesis of granitoids, u-pb zircon geochronology, sr-nd petrogenesis of granitoids, u-pb zircon geochronology, sr-nd isotopic characteristics, and important occurrence of tertiary mineralization within the lut block, eastern iran

tertiary intrusive granitoids within the lut block in the khorasan razavi and south khorasan provinces are mainly sub-volcanic with porphyry texture and their composition varies from granite to diorite but monzonite is dominant. with the exception of hired, these are classified as belonging to the magnetite-series of i-type granitoids. chemically, these rocks are meta-aluminous. those with mine...