Igneous rock associations 5. oceanic island volcanism II: mantle processes.(Series)

From: Geoscience Canada | Date: June 1, 2005| Author: Dostal, Jaroslav; Greenough, John D.; Mallory-Greenough, Leanne M. | Copyright information

SUMMARY

Oceanic island basalts (OIBs) have been central to understanding evolution of the Earth and mantle because their isolated positions in ocean basins limit the potential for magma contamination by continental crust. Melting processes (e.g., percentage melting) affect OIB chemistry but isotopic and trace-element ratios provide information on mantle-source compositions. They indicate that OIB mantle sources represent mixtures between mid-ocean ridge basalt (MORB) man...

Read all of this article with a FREE trial to HighBeam Research

Related newspaper, magazine, and journal articles from HighBeam Research

Investigation of the stock structure of Atlantic walrus (Odobenus rosmarus rosmarus) in Canada and Greenland using dental Pb isotopes derived from local geochemical environments.
Arctic ; ABSTRACT. The chemical composition of animal tissues such as teeth appears to reflect an individual's exposure to its geochemical environment. In this study, the lead (Pb) isotope composition of dental cementum was used to investigate the stock structure of Atlantic walrus (Odobenus rosmarus
U-Pb dating of stockwork zircons from the eastern Iberian Pyrite Belt
Journal of the Geological Society ; Zircons found in the stockwork zones of the massive sulphide Los Frailes deposit, Iberian Pyrite Belt, are interpreted to have grown during the hydrothermal alteration of host felsic volcanic rocks. Ion microprobe (SHRIMP) dating gives a ^sup 206^Pb/^sup 238^U age of 345.7 4.6 Ma (2sigma) and
Planetary science group honors Carl Sagan
The Milwaukee Journal Sentinel ; ... great joy at this that he wanted to convey," she said. "He wanted to reach out to the widest possible audience." Sagan wanted the news of what scientists were discovering to be shared with everyone, that it be "not an elite property but something that belongs ...
Two new Emsian (Early Devonian) U-Pb zircon ages from volcanic rocks of the Rhenish Massif (Germany): implications for the Devonian time scale
Journal of the Geological Society ; Abstract: So far, only few biostratigraphically well-constrained isotopic ages constitute the geochronological framework of the Devonian period. To expand this sparse dataset, two new U-Pb isotope dilution-thermal ionization mass spectrometry (ID-TIMS) zircon ages were obtained from volcanic rocks
SIMS U-Pb zircon ages for the Upper Devonian Snobs Creek and Cerberean Volcanics from Victoria, with age uncertainty based on UO^sub 2^/UO v. UO/U precision
Journal of the Geological Society ; Abstract: Sensitive high-resolution ion microprobe (SHRIMP) zircon ^sup 206^Pb/^sup 238^U ages for the Snobs Creek Volcanics and the overlying Cerberean Volcanics in central Victoria are analytically indistinguishable at 373.2 1.8 and 375.0 2.0 Ma (2[sigma The SHRIMP data provide a refined
A Martian haven for life?(PLANETARY SCIENCE)(Brief Article)
Science News ; Kevin Williams may have found one of the best places on Mars to look for past or present life. The region lies at the merger of two ancient riverbeds, the Samara and Parana-Loire Valles systems. But the past presence of water is only part of the reason why the area intrigues Williams and his
White Mars; Planetary science.(The geology of Mars)
The Economist (US) ; ... was put together quickly and efficiently. It cost about euro300m ($370m) to construct and dispatch. Using a spectrometer that maps Mars in visible and infra-red light, Dr Bibring's team has been able to create a detailed mineralogical map of most of the Martian ...
PICTURE OF SUCCESS BOULDER PLANETARY SCIENCE GROUP IS THRILLED THAT SATURN PROBE'S IMAGING TEAM IS JOINING ITS RANKS.(Local)
Rocky Mountain News (Denver, CO) ; Byline: Jim Erickson News Science Writer The head of the imaging team for NASA's $3.4 billion Cassini mission is trading the Arizona desert for the Colorado ...
CSA: Canadian Teachers Chosen for High Arctic Planetary Science Expedition
Marketwire ; LONGUEUIL, QUEBECMarketwire - July 17, 2008) - Two Canadian high school teachers will embark on a unique professional development opportunity in Canada's Far North, thanks to the Canadian Space Agency (CSA). Sean Clark of Stittsville, Ontario, and Genevieve Gingras Breton of Quebec, Quebec will
U-Pb dating of Mesozoic igneous rocks from Hong Kong
Journal of the Geological Society ; ... a 30 km wide zone bounded to the northwest by the Shenzhen Fault and to the southeast by the Haifeng Fault (Fig. 1). Tectonic maps for southeastern China indicate that this fault zone separates the South China Fold Belt to the northwest from the Southeast ...