Peer-reviewed articles 17,970 +



Title: STRESS INVERSION FROM FOCAL MECHANISM OF MODERATE EARTHQUAKES IN ALBANIA

STRESS INVERSION FROM FOCAL MECHANISM OF MODERATE EARTHQUAKES IN ALBANIA
E. Dushi; R.Koci; E.Begu;Rr. Bozo
1314-2704
English
18
1.1
The present study seeks to relate the focal mechanisms of moderate earthquakes, regional tectonics and the tectonic stress distribution, in Albania. We have analyzed 33 moderate earthquakes (2.2 ? MW ? 4.9) recorded in the time period 2013-2015, by the Albanian broadband (BB) seismic network. Events were located within the upper crust, in the depth range 0 ? h ? 17 km, showing the present day active tectonics. Formal stress inversion of the focal mechanism data, support the variation in the direction of the actual stress field as well as of the stress index R?, between the outer and the inner tectonic domains in Albanian, respectively under a compressional and extensional tectonic regime. Both domains are connected through Vlora-Lushnja-Elbasani-Dibra (VLED) transversal source zone, characterized by normal faulting with a strong strike-slip component. Orientation of the stress axes, ?1, ?2 and ?3, vary according to the respective zones. Thus, along the Adriatic coastal region, stresses have the orientation ?1(2?/66?), ?2(20?/335?) and ?3(70?/162?) showing a compressional stress regime (R = 0.15) directed E-NE (N65?E), while in the Ionian region it changes to ?1(31?/260?), ?2(17?/159?) and ?3(53?/45?), showing a compressional stress regime (R = 0.5) directed to EW (N94?S); In the inner domain of an extensional regime (R = 0.98), stress axis results oriented ?1(55?/116?), ?2(2?/24?), ?3(34?/292?), having a NE (N22?E) direction; Along the transversal zone (VLED), of oblique displacements (R= 0.49), results support the orientation ?1(20?/1?), ?2(67?/152?), and ?3 (10?/267?), where the horizontal stresses are directed almost southward (N178?E). Focal mechanism solutions and horizontal stresses SHmax and SHmin, inferred from the formal stress inversion of focal mechanism data, show a good agreement with previous studies and support the continental collision mechanism between Adria microplate and Albanian orogen.
conference
18th International Multidisciplinary Scientific GeoConference SGEM 2018
18th International Multidisciplinary Scientific GeoConference SGEM 2018, 02-08 July, 2018
Proceedings Paper
STEF92 Technology
International Multidisciplinary Scientific GeoConference-SGEM
Bulgarian Acad Sci; Acad Sci Czech Republ; Latvian Acad Sci; Polish Acad Sci; Russian Acad Sci; Serbian Acad Sci & Arts; Slovak Acad Sci; Natl Acad Sci Ukraine; Natl Acad Sci Armenia; Sci Council Japan; World Acad Sci; European Acad Sci, Arts & Letters; Ac
989-996
02-08 July, 2018
website
cdrom
123
tectonics; stress inversion; focal mechanism.