using flac3d for modeling sediments prograding wedge

Locating platforms at sites dictated by the need to avoid hydrates-rather than optimize production operations, as is the current practice-increases the cost of production and impedes the commercial development of such deposits.Ĭurrently, there is a lack of understanding of the mechanical and thermal properties of sediments containing gas hydrates, especially in marine deposits. Such concerns would only increase if the hydrate accumulations are themselves the target of development operations. The primary concern is that warm fluids rising in a wellbore from deeper reservoirs may cause gas hydrate in the neighborhood of a well or pipeline to dissociate, reducing the stability of the supporting sediments and placing significant investments at risk. Adapted from McIver (1982).Īs a result of this potential for submarine sediment dislocation, the placement of wells and seafloor-grounded platforms associated with oil and gas production is strongly influenced by the presence of gas hydrate on the sea floor or within the sediment lithology. Diagram showing the effects of gas hydrate dissociation on oceanic hillslope failures and gas release. Failure would be accompanied by the release of methane gas, but a portion of the methane is likely to be oxidized unless the gas release is catastrophic. Submarine slope failure can follow, giving rise to debris flows, slumps, slides, and collapse depressions such as described by Dillon, et al. The hydrates in any of these cases may be a part of the solid skeleton that supports overlying sediments, which in turn support the platforms and pipelines needed for producing conventional oil and gas resources, as well as natural gas from hydrates (when this becomes economically and technically possible).Īccordingly, the potential instability of HBS is a subject of critical importance, and past researchers have described the conditions under which hydrate dissociation in HBS produces an enhanced fluidized layer at the base of the gas-hydrate zone. Each of these hydrate accumulations may affect the seafloor stability differently. Gas hydrates exist in many configurations below the sea floor, including massive (thick solid zones), continuous layers, nodules, and as widely disseminated interstitial material.

Interagency Working Group Initial Report.

FECM Extramural R&D Final Technical Reports.

Solicitations and Funding Opportunities.

Strategic Systems Analysis and Engineering.

Materials Engineering and Manufacturing.

Cybersecurity, Energy Security, and Emergency Response.

Office of Energy Efficiency and Renewable Energy.

Rare Earth Elements & Critical Minerals.

Using flac3d for modeling sediments prograding wedge