Record details

Title
    Disputable non-double-couple mechanisms of several strong earthquakes: second-degree moment approach
Author
    Adamová, Petra
    Šílený, Jan
Language
    anglicky
Publication type
    článek v odborném periodiku
Source title - serial
    Bulletin of the Seismological Society of America
Vol./nr.
    Roč. 103, č. 5
Pages
    s. 2836-2849
Year
    2013
Notes
    Projekt: GAP210/10/0296, GA ČR3cav_un_auth*0263303
    Rozsah: 14 s. : P
Subject category
    1995 Kobe earthquake
    Izmit Turkey earthquake
    rupture processes
Keyword
    Approach
    Disputable
    Earthquakes
    Mechanisms
    Moment
    Non-double-couple
    Second-degree
    Several
    Strong
Abstract (in english)
   The earthquake source mechanism (description of the geometry of the source and its strength in terms of forces equivalent to rupturing of the rock mass) is routinely modeled as a moment tensor (MT) describing the earthquake focus as a point. However, sometimes this approximation is not satisfied, and seismic radiation keeps the directivity due to the finite extent of the source. Inversion into the MT then may yield a biased mechanism. Synthetic study in the Adamová and Šílený (2010) demonstrated the appearance of spurious non-double-couple components in the mechanism even for a pure double-couple (DC) source. Their method was designed to reduce the spurious source components by using the second-degree moments to evaluate their contribution into the records and subtract it from the data. Here we applied the procedure to five moderate to large regional events with large nonshear components.
   They are mostly located on large tectonic faults where predominantly pure shear slip is expected. We studied one event on the prominent North Anatolian fault, three events in the Pacific area, and one event in Bolivia.
Contributor
    AV ČR Brno, Geofyzikální ústav
Contributor code
    AV ČR, GFÚ
Source format
    U
Import date
    23. 10. 2014