Peer-reviewed articles 17,970 +



Title: HORIZONTAL STRESS FIELD IN THE EARTH CRUST OF ROMANIA USING MULTIPLE FOCAL MECHANISM SOLUTIONS

HORIZONTAL STRESS FIELD IN THE EARTH CRUST OF ROMANIA USING MULTIPLE FOCAL MECHANISM SOLUTIONS
A. Bala;D. T. Danila;M. Radulian
1314-2704
English
19
1.1
A catalogue of fault plane solutions for earthquakes recorded in Romania between 1929 and 2012 is analyzed in order to outline statistical features of the fault plane solutions in correlation with the earthquake-prone areas in Romania. The catalogue contains both groups: crustal earthquakes (h < 50 km) and intermediate-depth earthquakes (h > 50 km), but only the crustal earthquakes are analyzed here. The catalogue covers mostly the area in front of the Carpathians Arc: Moesian Platform, Barlad Depression, North Dobrogean Orogen and Fagaras ? Campulung, Central Southern Carpathian seismogenic zones. The Intra-Carpathians area has a sparse seismicity and the available fault plane solutions are not enough to derive regional horizontal crustal stress based on multiple mechanism solutions.
In our present investigations we have employed the formal stress inversions of a group of focal mechanisms (FMF), which is a better estimation of the tectonic stress orientation that can be achieved in a region with a homogeneous regional stress field, in comparison with single focal mechanism, as shown in World Stress Map Project . The formal stress inversion of multiple focal mechanisms (FMF) improves the quality of stress derivation, but it is linked to two main assumptions: (1) the chosen FMS lies in a region with a uniform stress field that is invariant in space and time; (2) the direction of earthquake slip follows the direction of the maximum shear stress, as in Wallace-Bott hypothesis .
The 2D horizontal stress is determined in the crustal zones using local grids with cells containing at least 15- 20 fault plane solutions and is graphically represented, using STRESSINVERSE computer programs with public access .
conference
19th International Multidisciplinary Scientific GeoConference SGEM 2019
19th International Multidisciplinary Scientific GeoConference SGEM 2019, 30 June - 6 July, 2019
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
839-846
30 June - 6 July, 2019
website
cdrom
4876
catalogs of earthquake mechanisms; seismic zones; horizontal stress in the crust; interpretation in tectonics terms.