Geological occurrence of gas hydrates at the Blake Outer Ridge, western North Atlantic

• Main Authors: Dominic, K.L., Barlow, D.L.
• Language: unknown
• Published: 2013
• Subjects: 03 NATURAL GAS; CONTINENTAL SHELF; NATURAL GAS HYDRATE DEPOSITS; GAS HYDRATES; GAS ANALYSIS; NATURAL OCCURRENCE; STABILITY; GEOLOGY; SEISMIC SURVEYS; ATLANTIC OCEAN; COMPARATIVE EVALUATIONS; EXPERIMENTAL DATA; GEOCHEMISTRY; GEOTHERMAL GRADIENTS; GULF OF MEXICO; PHASE DIAGRAMS; PHASE STABILITY; CARIBBEAN SEA; CHEMISTRY; CONTINENTAL MARGIN; DATA; DIAGRAMS; GEOLOGIC DEPOSITS; GEOPHYSICAL SURVEYS; HYDRATES; INFORMATION; NUMERICAL DATA; SEAS; SURFACE WATERS; SURVEYS; TEMPERATURE GRADIENTS; North Atlantic
• Online Access: http://www.osti.gov/servlets/purl/6263555; https://www.osti.gov/biblio/6263555; https://doi.org/10.2172/6263555

The occurrence of gas hydrates at the Blake Outer Ridge, as confirmed by the Deep Sea Drilling Project (DSDP), is governed not only by gas-water phase relationships but also by interrelated geological constraints. The results of this reexamination of the DSDP data show that seafloor processes, topography, and sediment properties are among the factors that impact the stability and distribution of gas hydrate at the ridge. Rapid sedimentation and erosion have local and transient effects on thermal gradients, which cause the base of the hydrate stability zone to migrate. To a large degree, the convex shape of the Blake Outer Ridge allows gas hydrates to be stable. Low-permeability sediments occupy the interval in which the stability zone exists, and they influence hydrate occurrence by controlling the distribution of gas. A brief comparison of the Blake Outer Ridge with two more recently confirmed hydrate localities (the northern Gulf of Mexico and the Middle America's trench) shows little similarity among the three hydrate environments, but calls attention to the complex and often subtle effects that the geological system imposes on hydrate stability. 47 refs., 8 figs., 2 tabs.