← Back to Sessions

Moment Tensor Analysis for Earthquakes in Armenia

Description: 

The Republic of Armenia and the neighboring areas are located in the central part of the Arabia-Eurasia collision zone, characterized by active seismicity. Moment tensor analysis (MTA) was carried out for the earthquakes (M>=3.0) that occurred in the territory of Armenia from 2017 to 2021. The data for this analysis were collected from a temporary broadband regional network, part of the project Collaborative Research: The Uplift and Seismic Structure (CNET). The inversion for the moment tensor, centroid depth, and source time function involves modeling the entire 3-component seismograms (Nabelek and Xia, 1995). For each earthquake, seismograms were band-pass filtered to enhance the signal. Earthquakes of magnitude 3.0 and greater were well recorded by many stations, resulting in well-resolved estimated parameters. Most events suitable for the moment-tensor analysis occurred in Javakheti and northwest Armenia regions and are right-lateral strike-slip, with two outliers, normal fault and thrust fault. A right-lateral strike-slip event near Vanadzor is consistent with the slip on the Pambak-Sevan fault. The most significant event (Mw=4.7) near Yerevan has a mixed strike-slip-thrust mechanism with a west-oriented tension axis. For this event was also calculated focal mechanism solution using P-wave first motion method, which shows that this 2021 M4.9 earthquake is characterized by a thrust fault mechanism with a strike-slip component (Sargsyan L., et al. 2022). The discussion of historical seismicity that has occurred over the course of a century in direct proximity to Yerevan, demonstrates that the Yerevan Fault and Parakar sub-fault are seismically active systems. The problem of possible NW and SE extensions of the Yerevan fault was addressed.

Session: Learning Across Geological, Geophysical & Model-Derived Observations to Constrain Earthquake Behavior [Poster Session]

Type: Poster

Date: 5/1/2024

Presentation Time: 08:00 AM (local time)

Presenting Author: Elya

Student Presenter: No

Invited Presentation: 

Authors