Predicting hydrocarbon potential of an earth formation underlying a body of water by analysis of seeps containing low concentrations of methane using improved cryogenic entrapment

摘要

The present invention provides for on-site capture of methane at sea at dry ice temperature, for isotopic examination. In more detail, after interfering gas species have been removed from subsequent operational steps, the methane is oxidized to carbon dioxide and water vapor, which are then trapped with a trapping tube maintained at dry ice temperature. The tube also houses a bed of granules made of porous polymer cross- linked to form a lattice network for retention of the carbon dioxide without a change in phase. Thereafter, the carbon and deuterium distribution of the oxidized methane products, carbon dioxide and water vapor, are determined by isotopic examination so as to establish their biogenic and/or thermogenic origin.