Details

Autor(en) / Beteiligte

• Karakhanyan, A.
• Vernant, P.
• Doerflinger, E.
• Avagyan, A.
• Philip, H.
• Aslanyan, R.
• Champollion, C.
• Arakelyan, S.
• Collard, P.
• Baghdasaryan, H.
• Peyret, M.
• Davtyan, V.
• Calais, E.
• Masson, F.

Titel

GPS constraints on continental deformation in the Armenian region and Lesser Caucasus

Ist Teil von

• Tectonophysics, 2013-04, Vol.592 (592), p.39-45

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2013

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• We present the 1998–2009 GPS-derived velocity field for the Armenia region based on a survey-mode observation network of 31 GPS sites. We combine our results with previous GPS studies of the region to better assess the deformation of the Lesser Caucasus and Kura basin region. The results show that the Kura basin and the Lesser Caucasus regions are two different blocks, and that the main fault (Pambak–Sevan–Sunik) between these two regions has a right-lateral slip rate of 2±1mm/yr. This is consistent with morphotectonic estimates and suggests a fairly constant slip rate over the last 120–300ka. The right-lateral slip rate on one of the southern branch of the Pambak–Sevan–Sunik fault is lower than 1mm/yr and the good agreement with a geologically estimated slip rate suggests a constant slip rate over the last 1.4Myr. The Sardarapat and Akhurian faults experience some shortening. This shortening is consistent with some independent geological estimates and shows the Arabian push. However, NNW-SSE-orientated faults have an extensional fault normal component instead of the expected shortening due to the Arabia–Eurasia convergence. This substantial extensive strain, and the sharp azimuth change of the velocity vectors between the Arabia promontory and the Lesser Caucasus suggest that processes other than “extrusion”, possibly related to old subduction or delamination, contribute to the geodynamics of the region. ► We present a new GPS velocity field with 31 more GPS sites. ► We model this velocity field with a block model. ► The Pambak-Sevan-Sunik fault has a right lateral slip rate of ~2mm/yr. ► The other Armenian faults have a slip rate below 1mm/yr.