Publication date: 1999-09-01
First published in: Offshore Magazine
Authors: J. Laherrere
Methane hydrates are well known to the oil industry as a material for clogging pipelines and casings. They are also present in permafrost areas and the oceans. Oceanic hydrates are mainly biogenic and different from thermogenic hydrates.
Claims for widespread hydrate occurrence in thick oceanic deposits are unfounded. The thickest interval recovered from a total of 250,000 meters of core from 2,300 ODP/DSDP boreholes was one meter. Mostly, they occur as dispersed grains and laminae. Indirect evidence from BSR, seismic direct hydrocarbon indicators, logs, and free gas samples is unreliable and highly speculative.
Being a solid, methane in oceanic hydrates cannot migrate and accumulate in deposits sufficiently large to be commercially exploited. The published estimates of the size of the resource are highly unreliable and give flawed comparisons with conventional fossil fuels. There are other non-conventional sources of gas which are better known and more accessible than hydrates, yet remain uneconomic. The prospects for the commercial production of oceanic hydrates in the foreseeable future are negligible. The academic research dedicated to hydrates has produced more questions than answers at this stage.
Published: Offshore, Volume 59 Issue 9 September 1999
Available from: Offshore Magazine