Hydrogeochemistry of the northern Barbados accretionary complex transect: Ocean Drilling Project leg 110

Journal Article · Sun Jun 10 00:00:00 EDT 1990 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JB095iB06p08809· OSTI ID:5073575

Gieskes, J M ^[1]; Vrolijk, P ^[2]; Blanc, G ^[3]

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1. Univ. of California, San Diego, La Jolla, CA (United States)
2. Univ. of Michigan, Ann Arbor (United States)
3. Univ. Louis Pasteur, Strasbourg (France)

Detailed studies of the major element geochemistry, oxygen and hydrogen isotope ratios of pore fluids, and the {sup 87}Sr/{sup 86}Sr ratio of dissolved strontium have made it possible to unravel physical and chemical processes that affect the pore fluid chemistry in a transect of drill holes across the northern Barbados accretionary complex. These processes include (1) alteration of volcanic ash buried in the Pleisticene-Pliocene sediment column; (2) alteration of underlying basalts of layer 2 of the oceanic crust; (3) movement of fluids from deep in the accretionary complex along fault zones (particularly the decollement) and minor permeable layers; these fluids from deeper in the complex are characterized by low chloride concentrations and increased {sup {delta}18}O(H{sub 2}O) values, presumably as a result of dehydration of smectite interlayers; and (4) mixing processes involving the migrating fluids cause incongruities in the geochemical anomalies of these fluids.

• OSTI ID: 5073575
• Journal Information: Journal of Geophysical Research; (United States), Vol. 95:B6, Issue B6; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
BARBADOS
GEOLOGIC FORMATIONS
GEOCHEMISTRY
INTERSTITIAL WATER
ISOTOPE RATIO
BASALT
BOREHOLES
CHLORIDES
GEOLOGIC FAULTS
HYDROGEN ISOTOPES
HYDROTHERMAL ALTERATION
OCEANIC CRUST
OXYGEN 18
OXYGEN ISOTOPES
SMECTITE
STRONTIUM 86
STRONTIUM 87
VOLCANIC ROCKS
ALKALINE EARTH ISOTOPES
BETA DECAY RADIOISOTOPES
CAVITIES
CHEMISTRY
CHLORINE COMPOUNDS
CLAYS
EARTH CRUST
ELECTRON CAPTURE RADIOISOTOPES
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
GROUND WATER
HALIDES
HALOGEN COMPOUNDS
HOURS LIVING RADIOISOTOPES
HYDROGEN COMPOUNDS
IGNEOUS ROCKS
INTERMEDIATE MASS NUCLEI
ISLANDS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LESSER ANTILLES
LIGHT NUCLEI
MINERALS
NUCLEI
OXYGEN COMPOUNDS
RADIOISOTOPES
ROCKS
SILICATE MINERALS
STABLE ISOTOPES
STRONTIUM ISOTOPES
WATER
WEST INDIES
580000* - Geosciences