Seismic identification of gas hydrates: a case study from Sakarya Canyon, western Black Sea

Aslıhan NASIF; Faik Erdeniz " ÖZEL; Derman DONDURUR

Article Details

Seismic identification of gas hydrates: a case study from Sakarya Canyon, western Black Sea

Authors:

Aslıhan NASIF | Faik Erdeniz " ÖZEL | Derman DONDURUR

Publisher:

TUBITAK

Main Topics:

Applied physics

Journal:

Turkish Journal of Earth Sciences 2020 Vol.29 Issue 3, pp.434-454

Document Type:

Article

Publication Date:

3/2020

Document Language:

English

Document ID (Org No.):

2000730848

Frequency:

Bimonthly

eISSN:

1303-619X

pISSN:

1300-0985

Abstract:

 

Multichannel seismic, 3.5-kHz Chirp subbottom profiler and multibeam bathymetric data were collected along the western Black Sea margin, offshore Sakarya River, to investigate the bottom-simulating reflections (BSRs), free gas accumulations, and mud volcanoes. Geometries from the seismic data indicate widespread BSRs along the continental rise between 750 and 1950 m water depths, 70 to 350 ms below the seafloor. Seismic attribute analyses have been applied to the seismic data to reveal the acoustic properties of the gas hydrates. According to the results from such analyses, we conclude that there are acoustically transparent zones beneath most of the BSRs in the area, which are interpreted as free gas accumulations, and the gas hydrate-bearing sediments are acting as seals for the free gas in the underlying sediments. Stability analysis of the gas hydrates from different BSR zones in the area suggests that the gas composition in the gas hydrates may change locally. As we do not have ground truth data from BSR zones, the exact composition of the gas forming the gas hydrates is unknown. However, hydrocarbon productivity of the area, chromatography results of the shallow sediment samples nearby, and stability analysis of the gas hydrates indicate the possible existence of a thermogenic gas component in the gas hydrate composition, resulting in a mixture of gas hydrates.

Article Details

Seismic identification of gas hydrates: a case study from Sakarya Canyon, western Black Sea

Authors: Aslıhan NASIF | Faik Erdeniz " ÖZEL | Derman DONDURUR

Publisher: TUBITAK

Main Topics: Applied physics

Journal: Turkish Journal of Earth Sciences 2020 Vol.29 Issue 3, pp.434-454

Document Type: Article

Publication Date: 3/2020

Document Language: English

Document ID (Org No.): 2000730848

Frequency: Bimonthly

eISSN: 1303-619X

pISSN: 1300-0985

Issues

Authors:

Aslıhan NASIF | Faik Erdeniz " ÖZEL | Derman DONDURUR

Publisher:

TUBITAK

Main Topics:

Applied physics

Journal:

Turkish Journal of Earth Sciences 2020 Vol.29 Issue 3, pp.434-454

Document Type:

Article

Publication Date:

3/2020

Document Language:

English

Document ID (Org No.):

2000730848

Frequency:

Bimonthly

eISSN:

1303-619X

pISSN:

1300-0985