Publication Date:
2024-02-07
Description:
Highlights
• In-situ temperature measurements were conducted at the Danube deep sea fan.
• Operations were performed with the MARUM-MeBo200 seafloor drill rig.
• The BSR is located ∼20 m below the current gas hydrate stability zone.
• Seismic data suggest presence of shallower BSR-like events.
Abstract
Coring, geophysical logging, and in-situ temperature measurements were performed with the MARUM-MeBo200 seafloor rig to characterize gas hydrate occurrences in sediments of the Danube deep sea fan, off Romania, Black Sea. The new drilling data showed no evidence for significant gas hydrate saturations within the sediments but the presence of free gas at the depth of the bottom-simulating reflector (BSR). In-situ temperature and core-derived geochemical data suggest that the current base of the gas hydrate stability zone (BGHSZ) is ∼20 m shallower than the BSR. Investigation of the seismic data around the drill sites shows several locations where free gas previously trapped at a former BGHSZ migrated upwards forming a new reflection above the BSR. This shows that the gas hydrate system in the Danube deep sea fan is still responding to climate changes initiated at the end of the last glacial maximum.
Type:
Article
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PeerReviewed
,
info:eu-repo/semantics/article
Format:
text
Format:
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Format:
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Format:
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