Reassessment of the Rates at which Oil from Natural Sources Enters the marine environment

Abstract

Previous estimates of the world-wide input of oil to the marine environment by natural seeps ranged from 0"2 to 6.0 million (metric)

Hydrates of Natural Gases and Small Molecules: Structures, Properties, and Exploitation Perspectives

“…Several reviews on this subject have been reported by Kvenvolden and co-workers. [83][84][85][86] Extensive research was performed by the ODP on the Blake Bahamas Ridge (between Bahamas Island and Cape Hatteras, North Carolina), [87][88][89] and other offshore locations as on Barklay Canyon out of Vancouver Island on the northern Cascadian Margin (Canadian Remotely Operated Platform for Ocean Science (ROPOS) project; Integrated Oceanic Drilling Project (IODP)), [90,91] at Bush Hill in the Green Canyon, [92][93][94] in the Mississippi Canyon of the Mexican Gulf, [95] on the southern summit of the Hydrate Ridge at the Oregon Margin, [94] and on the Håkon Mosby site in the Norwegian Sea. [95] More recently a successful exploration was tried on the Tigershark field in Alaminos Canyon in the Gulf of Mexico.…”

Implications of Surface Seepage on the Effectiveness of Geologic Storage of Carbon Dioxide as a Climate Change Mitigation Strategy

“…For example, worldwide oil seepage is estimated to be 0.2 Million tonnes/year out of a total reservoir of 10 7 Mt (assuming 50 Myr residence time), or on the order of 10 -8 /year [5]. Although less is known about the ability of brine formations to retain buoyant gases, detailed site-specific studies and careful site selection can be used to identify sites with seepage rates that meet the performance requirements identified above.…”

“…Note that surface seepage is not necessarily equal to the rate at which CO 2 leaks from the primary storage reservoir, as the existence of stacked reservoirs [3,4] and natural seeps [5,6] demonstrates. Many subsurface processes such as solubility trapping, mineralization, diffusion, and residual gas trapping will attenuate the migration of CO 2 as it moves towards the land surface.…”

Gaia's breath—global methane exhalations

“…This approach involved broad assumptions based on considerations of the availability of CH 4 for seepage from all global geological sources through geologic time. The method used was adopted from previous work dealing with global estimates of crude oil seepage (Kvenvolden and Harbaugh, 1983;Miller, 1992). The total reservoir of CH 4 was estimated to be between 10 4 and 10 8 Tg and the half-life of this reservoir was set at 10 8 yr.…”