Acoustic evidences of gas in the continental slope sediments of the Gulf of Cadiz (E Atlantic)

被引:33
作者
Casas, D [1 ]
Ercilla, G [1 ]
Baraza, J [1 ]
机构
[1] CSIC, Inst Ciencias Mar, E-08003 Barcelona, Spain
关键词
D O I
10.1007/s00367-003-0160-z
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Detailed reviews of high-resolution acoustic studies in the continental slope of the Gulf of Cadiz has revealed the following gas-related features: acoustic turbidity and blanking, bright spots, ancient and modern pockmarks, high-amplitude diffractions, acoustic plumes and turbidity in the water column, and BSRs. The origin of the gas is believed to be biogenic and thermogenic. The BSR-like acoustic anomalies occur intermittently in some areas of the upper slope and tend to occur in the volcanoes/diapirs. The pressure-temperature conditions deduced for the location of those acoustic anomalies do not correspond to the conditions of stability of gas hydrates. It is suggested that these volcanoes/diapirs intrusions may locally induce anomalously higher pore pressure conditions on the immediately surrounding sediments, affecting the stability field of the gas hydrates.
引用
收藏
页码:300 / 310
页数:11
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