Zobrazeno 1 - 10
of 153
pro vyhledávání: '"Robert Kerrich"'
Autor:
Robert Kerrich, Yiefei Jia
Publikováno v:
Lithos. 233:131-138
The nitrogen isotopic composition of the Earth's primitive mantle is controversial. Chromium-isotopic ratios of various terrestrial minerals and rocks, and chondritic meteorites are consistent with the silicate Earth being a mixture of enstatite and
Autor:
T. Campbell McCuaig, Zhiming Yang, Leon Bagas, Noreen J. Evans, Zheng-Xiang Li, Anthony I.S. Kemp, Peter A. Cawood, Fred Jourdan, Yongjun Lu, Zengqian Hou, Robert Kerrich, John B. Cliff, Craig J.R. Hart, Elena Belousova
Publikováno v:
Economic Geology. 108:1541-1576
The Yao’an porphyry Au system, Machangqing porphyry Cu-Mo system, and Beiya porphyry-skarn Au system, are spatially and temporally associated with potassic felsic intrusions emplaced during the Eocene to Oligocene epochs at 37 to 33 Ma in a postcol
Publikováno v:
Lithos. 177:120-135
Two compositionally different ultramafic units are present in the Neoarchean Sigegudda greenstone terrane, Western Dharwar Craton, India. These ultramafic units occur in the same volcano-sedimentary sequence and are separated by a fault-bounded volca
Publikováno v:
Gondwana Research. 23:506-525
Hydrothermally altered Archean igneous suites erupted in the submarine environment record variable excursions of Ce/Ce* and Th/U from primary magmatic values of 1 and ~ 4 respectively. Rhyolites of the 2.96 Ga bimodal basalt–rhyolite sequence of th
Publikováno v:
Precambrian Research. 224:110-128
Komatiite–basalt magmatism and Algoma-type banded iron formation (BIF) of Archean greenstone terranes have common time series, but there are few constraints on the geodynamic setting in which BIF were precipitated. The ∼3.0 Ga Koolyanobbing green
Autor:
Ali Polat, Brian J. Fryer, Christopher G. Weisener, Fred J. Longstaffe, Robert Frei, Robert Kerrich
Publikováno v:
Chemical Geology. :145-173
This study reports petrographic, major and trace element, and oxygen isotopic data for a subaerial weathering profile at Schreiber Beach, Ontario, Canada. The weathering profile developed on Neoarchean ( ca. 2.7 Ga) pillow basalts and is unconformabl
Autor:
Zheng-Xiang Li, Zengqian Hou, Peter A. Cawood, Craig J.R. Hart, T. Campbell McCuaig, Leon Bagas, Yongjun Lu, Robert Kerrich
Publikováno v:
Gondwana Research. 22:737-747
The relationship between potassic felsic intrusions, cospatial and cotemporal with potassic mafic magmatism, and strike–slip displacement along the Ailao Shan-Red River shear zone in western Yunnan, SW China has been highly controversial. We report
Publikováno v:
Precambrian Research. :207-224
A rare association of basalt, andesite, dacite and ultrapotassic volcanic flows is present, together with basalts, komatiites, and banded iron formation (BIF), in the Neoarchean Sigegudda greenstone terrane of the western Dharwar craton. Andesites an
Publikováno v:
Australian Journal of Earth Sciences. 59:737-763
A database of 1075 high-precision geochemical analyses of least-altered ultramafic–mafic units, predominantly flows, was compiled for the Eastern Goldfields Superterrane. Samples are divided into a high-Mg population at MgO≥10–24 wt% and a basa
Publikováno v:
Precambrian Research. :174-196
The Mesoproterozoic Belt-Purcell Supergroup (BPS) preserves a thickness of 17 km of dominantly siliciclastic rocks deposited between 1470 and 1400 Ma. The total range of Chemical Index of Alteration (CIA) values, corrected for diagenetic K-addition,