00000nam 2200000za 4500 9.820662 CaOODSP 20230131161136 cr ||||||||||| 160708s2015 oncabd ob f000 0 eng d 978-0-660-03233-7 CaOODSP eng eng fre n-cn-nt M44-2015/8E-PDF Evidence for a deep gas-hydrate stability zone associated with submerged permafrost on the Canadian Arctic Beaufort Shelf, Northwest Territories [electronic resource] / M. Riedel … [et al.]. [Ottawa] : Natural Resources Canada, 2015. 17 p. : col. charts, col. ill., col. maps. Current research, 1701-4387 ; 2015-8 Includes bibliographical references. "The presence of offshore permafrost on the Canadian Beaufort Sea Shelf has long been recognized from seismic and borehole data. These thermal conditions could support a gas hydrate stability zone beneath the subsea permafrost. In this study we present the first evidence for the widespread occurrence of gas hydrate on the Beaufort Shelf using 3-D seismic data. A reflector was identified at a depth of ~1000 m that mimics some of the behaviour of the traditional bottom-simulating reflectors (BSRs) in marine gas hydrate regimes. However, the reflection is not truly bottom-simulating, as its depth is controlled by the thinning wedge of subsea permafrost. The reflection cross-cuts strata and marks a zone of enhanced reflectivity, possibly originating from free gas accumulated at this phase boundary. Implications of this widespread gas hydrate zone include: deep-drilling hazards associated with the free gas, potential overpressure, lateral fluid migration and associated seafloor expulsions"--Provided by publisher. gccst Ocean floor gccst Permafrost gccst Natural gas gccst Geophysics gccst Seismology Riedel, Michael. Canada. Natural Resources Canada. Geological Survey of Canada. Current research (Geological Survey of Canada) 1701-4387 ; 2015-8. (CaOODSP)9.506236 PDF 13.87 MB https://publications.gc.ca/collections/collection_2016/rncan-nrcan/M44-2015-8-eng.pdf 296987