Gas hydrate stability zone modelling in areas of salt tectonics and pockmarks of the Barents Sea suggests an active hydrocarbon venting system

被引：56

作者：

Chand, S. ^{[1
]}

Mienert, J. ^{[2
]}

Andreassen, K. ^{[2
]}

Knies, J. ^{[1
]}

Plassen, L. ^{[3
]}

Fotland, B. ^{[4
]}

机构：

[1] Geol Survey Norway, N-7491 Trondheim, Norway

[2] Univ Tromso, Tromso, Norway

[3] Geol Survey Norway, N-9296 Tromso, Norway

[4] STATOIL, Harstad, Norway

来源：

MARINE AND PETROLEUM GEOLOGY | 2008年 / 25卷 / 07期

关键词：

gas hydrate; pockmark; seismic;

D O I：

10.1016/j.marpetgeo.2007.10.006

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

The Barents Sea seabed exhibits an area of major glacial erosion exposing parts of the old hydrocarbon basins. In this region, we modelled the gas hydrate stability field in a 3D perspective, including the effects of higher order hydrocarbon gases. We used 3D seismic data to analyse the linkage between fluid-flow expressions and hydrate occurrences above old sedimentary basin systems and vertical faults. Pockmarks showed a relation to fault systems where some of them are directly connected to hydrocarbon bearing sedimentary formations. The influence of bottom water temperature, pore water salinity and geothermal gradient variation on gas hydrate stability zone (GHSZ) thickness is critically analysed in relation to both geological formations and salt tectonics. Our analysis suggests a highly variable GHSZ in the Barents Sea region controlled by local variations in the parameters of stability conditions. Recovery of gas-hydrate sample from the region and presence of gas-enhanced reflections below estimated BSR depths may indicate a prevalent gas-hydrate stable condition. (c) 2007 Elsevier Ltd. All rights reserved.

引用

页码：625 / 636

页数：12

共 60 条

[1] Three-dimensional seismic data from the Barents Sea margin reveal evidence of past ice streams and their dynamics [J].