Stress tensor inversions along the westernmost North Anatolian Fault Zone and its continuation into the North Aegean Sea

Details Stress tensor inversions along the westernmost North Anatolian Fault Zone and its continuation into the North Aegean Sea Stress tensor inversions along the westernmost North Anatolian Fault Zone and its continuation into the North Aegean Sea

Nov 2002

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002geoji.151..360k&link_type=abstract

Geophysical Journal International, Volume 151, Issue 2, pp. 360-376.

Astronomy and Astrophysics

Astronomy

15

Anatolia, Fault-Plane Solutions, Greece, Stress Tensor Inversion

Scientific paper

Gephart & Forsyth's method has been applied to estimate stress orientations from earthquake fault-plane solutions of the westernmost North Anatolian Fault zone (NAFZ), its westward continuation in the Northern Aegean Sea, where it interacts with the normal faulting of central Greece, and of the western coastal parts of Anatolia. In total, 163 fault-plane solutions were used to invert for the stress tensor of 9 seismotectonic subregions. Magnitudes range from 1.1 to 7.4. All events have shallow focal depths; most occurred in the uppermost 15 km and very few in the 15 to 40 km depth range. The region studied is characterized by strike-slip (NAFZ), by transtension (Central Greece and western Anatolia) and by a strong signature of transpression in the Marmara area. From NAFZ to central Greece, the σ3 axis changes, continuously and smoothly, its orientation from N35°E in the westernmost NAFZ to nearly North-South in continental central Greece, and the maximum horizontal stress, σHmax changes from WNW-ESE to ~E-W. The total angle of lateral variation in the direction of either σHmax or σ3 is ~40°. In central western Anatolia the orientation of σ3 is NNE-SSW (N10°E) while in southern western Anatolia it is NNW-SSE (N33°W). In both cases the development of the major grabens (Simav, Gediz, Menderes) is in agreement with the resolved stress tensor. At the termination of the NAFZ against central Greece the regime is complex. The dextral shear motion transferred from the east crosses the Pilion peninsula and northern Evia Island where it interacts with the major normal faults of continental Greece. These faults have variable orientations. The E-W trending Quaternary fault system and the NW-SE trending fault system, which is inherited from the past. The latter faults under the presently acting stress field are reactivated either as strike-slip faults with sinistral strike-slip component (when oriented at small angle in respect to σ3) or as normal faults with small sinistral strike-slip component (when oriented at high angle in respect to σ3). The occurrence of the recent 2001 July 26 Skyros event, which was clearly connected to a NNW-SSE fault with sinistral strike-slip motion, provides strong seismological evidence that the old structures can equally well be reactivated under the presently active stress field.

Affiliated with

Also associated with

No associations

Rating

Stress tensor inversions along the westernmost North Anatolian Fault Zone and its continuation into the North Aegean Sea does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Stress tensor inversions along the westernmost North Anatolian Fault Zone and its continuation into the North Aegean Sea, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stress tensor inversions along the westernmost North Anatolian Fault Zone and its continuation into the North Aegean Sea will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-740669