Carbon isotopes in xenoliths from the Hualalai Volcano, Hawaii, and the generation of isotopic variability

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Geochimica et Cosmochimica Acta; (USA)

DOI:https://doi.org/10.1016/0016-7037(90)90209-4· OSTI ID:6692265

Pineau, F ^[1]; Mathez, E A ^[2]

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1. Univ. de Paris (France)
2. American Museum of Natural History, New York (USA)

The isotopic composition of carbon has been determined in a suite of xenoliths from lava of the 1800-1801 Kaupulehu eruption of Hualalai Volcano, Hawaii. Several lithologies are represented in the suite, including websterite, dunite, wehrlite, pyroxenite, and gabbro. In addition, there are composite xenoliths in which contacts between lithologies are preserved. Most of the xenoliths represent deformed cumulates. The contact relations in the composite samples indicate that the lithologies originated from the same source region, which, based on pressures determined from fluid inclusions, is estimated to be at a depth of {approx}20 km, or near the crust-mantle boundary. The observations and isotopic results demonstrate that isotopic variability can be generated by multistage fractionation processes such as degassing of CO{sub 2} from magma and precipitation of CO{sub 2}-rich fluids to form graphitic compounds. Such processes operated over regions the scales of which were determined by style and intensity of deformation and by lithology.

• OSTI ID: 6692265
• Journal Information: Geochimica et Cosmochimica Acta; (USA), Vol. 54:1; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
INCLUSIONS
GEOCHEMISTRY
MINERALOGY
VOLCANIC ROCKS
PETROGENESIS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON ISOTOPES
DEGASSING
FRACTIONATION
HAWAII
ISOTOPE RATIO
LAVA
LITHOLOGY
VARIATIONS
VOLCANOES
CARBON OXIDES
CHALCOGENIDES
CHEMISTRY
FEDERAL REGION IX
IGNEOUS ROCKS
ISOTOPES
NORTH AMERICA
OXIDES
OXYGEN COMPOUNDS
ROCKS
SEPARATION PROCESSES
USA
580000* - Geosciences