Cold seeps, active faults and the earthquake cycle along the North Anatolian Fault system in the Sea of Marmara (NW Turkey).

Gasperini, L., Polonia, A., Del Bianco, F., Favali, P., Marinaro, G. and Etiope, G. (2012) Cold seeps, active faults and the earthquake cycle along the North Anatolian Fault system in the Sea of Marmara (NW Turkey). Bolletino di Geofisica Teorica ed Applicata, 53 (4). pp. 371-384.

[img] Text
bgta0082_GASPERINI.pdf - Published Version
Restricted to Registered users only

Download (6Mb)

Abstract

After the 1999 I . zmit earthquake (Mw7.4), along the North-Anatolian Fault (NAF), an increase in gas emissions from the seafloor of the Sea of Marmara was observed. Using a multidisciplinary approach, that includes a combined analysis of high-resolution marine geophysical and gas-geochemical data, we determined the character of gas/fluid emissions and their spatial relationship with tectonic structures in the Darıca Basin (Gulf of Izmit), close to the western termination of the 1999 earthquake surface rupture. Data collected during several oceanographic expeditions allowed us to investigate the fine structure of active fault branches, as well as the geochemical signature of the cold seeps. We observed that gas emissions at the seafloor of the Darıca Basin are mostly constituted by biogenic CH4, and are aligned along strike-slip and transtensional fault segments. Although maximum CH4 concentrations were measured in correspondence of transtensional strands, we suggest that the biogenic CH4 emissions found along strike-slip segments, showing a relatively low gas background noise and a potential to increase during seismic events, are more suitable to study relationships between gas expulsion and the earthquake cycle.

Document Type: Article
Keywords: cold seep; earthquake cycle; Izmit earthquake; Gulf of Izmit; North Anatolian Fault (NAF); Sea of Marmara; seafloor observatories
Refereed: Yes
Open Access Journal?: Yes
ISSN: 0006-6729
Projects: FLOWS
Date Deposited: 11 Mar 2014 12:07
Last Modified: 11 Mar 2014 12:07
URI: http://oceanrep.geomar.de/id/eprint/23746

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...