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Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines

T.A. Abrajano·N.C. Sturchio·B. M. Kennedy·G.L. Lyon·K. Muehlenbachs·J.K. Böhlke
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Abstract

Methane-hydrogen gas seeps with mantle-like C and noble gas isotopic characteristics issue from partially serpentinized ultramafic rocks in the Zambales ophiolite, Philippines. New measurements of noble gas and 14 C isotope abundances, rock/mixed-volatile equilibrium calculations, and previous chemical and isotopic data suggest that these reduced gases are products of periodotite hydration. The gas seeps are produced in rock-dominated zones of serpentinization, and similar gases may be ubiquitous in ultramafic terranes undergoing serpentinization.

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T.A. Abrajano, N.C. Sturchio, B. M. Kennedy, G.L. Lyon, K. Muehlenbachs, J.K. Böhlke. 1990. Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines. https://doi.org/10.1016/0883-2927(90)90060-i

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