Marine Heat flow measurements from the submerged section of the North Anatolian Fault, in the Sea of Marmara
Abstract
For the first time, marine heat flow data were collected in the Sea of Marmara, in 2007, during the MarNaut cruise of R/V L'Atalante. A total of 45 heat flow measurements were carried out along three transects, respectively : the Tekirdag, the Central and the Cinarçik basins. The data were collected using 7 Micrel autonomous digital temperature probes fitted on a 10 cm-diameter gravity corer (the tube length was 10 m for the first 5 measurements ; 5 m for the remaining ones). The thermal profiles are linear, except near the very surface, where slight changes in water bottom temperature can be suspected. The measured heat flow values range between about 15 and 55 mW.m-2, except at one single location near the northern Cinarcik Basin escarpment, where heat flow reaches 120 mW.m-2, probably in response to deep, upward fluid flow. The measured values are lower than the published regional heat flow averages, which are of about 50 to 60 mW.m-2 and of about 100 mW.m-2 north and south of the Sea of Marmara, respectively. The lowest values correspond to the basins depocenters, where the syn-rift sediment cover is thickest, which suggests strong thermal sediment blanketing effects. Near the edges of the basins, effects resulting from basement topography are also suspected. Corrections are made to account for both effects, assuming different scenarii for the temporal and spatial evolution of the sedimentation rate. The computation results provide constraints to estimate the age of initiation of the North Anatolian Fault within what is now the Sea of Marmara.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFM.T44B..02G
- Keywords:
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- 3045 Seafloor morphology;
- geology;
- and geophysics;
- 8111 Continental tectonics: strike-slip and transform;
- 8130 Heat generation and transport;
- 8169 Sedimentary basin processes;
- 9335 Europe