Ground movements associated with gas hydrate production

Conference · Fri May 01 04:00:00 EDT 1992

OSTI ID:138856

Siriwardane, H J ^[1]

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1. West Virginia Univ., Morgantown (United States)

Gas hydrate as an energy reserve is very attractive in view of the large amount of gas that can be produced. Vast amounts of natural deposits of hydrates have been identified and a number of conceptual models have been developed for recovery of this resource. In the development of extraction technology for gas hydrates, it is necessary to have an understanding of the geomechanical behavior of hydrate reservoir and the overburden. An obvious consequence of hydrate dissociation is the compression of reservoir matrix causing displacements in the surrounding area. The reservoir compression is a time-dependent process which depends on the production rate. The ground movements cause additional stresses in the overburden which may result in rock mass fracture and failure. Rock failure may cause rubble formation or bulking in the fracture zone. This in turn can cause an increase in permeability for gas flow which may offset the reduction in permeability caused by closure of existing fractures during reservoir compression. Potential strata movements and subsidence associated with reservoir compaction during hydrate production has been investigated by using an analogy of gob compaction in a longwall mine. In this study, the thickness of the hydrate reservoir was assumed to be 50 feet. The depth of the reservoir was varied as 1,500 feet and 2,500 feet.

• Research Organization: USDOE Morgantown Energy Technology Center, WV (United States)
• OSTI ID: 138856
• Report Number(s): DOE/METC--92-6125; CONF-920584--; ON: DE92001278
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
FRACTURING
GAS HYDRATES
GEOLOGIC STRUCTURES
GROUND MOTION
GROUND UPLIFT
NATURAL GAS HYDRATE DEPOSITS
OVERBURDEN
ROCK MECHANICS
SOIL MECHANICS