5.9 Mw, 18th June 2010 earthquake and fault segment linkage at Andaman – A study based on macroseismic survey, GPS geodesy and Coulomb stress changes

18th June, 2010 5.9 Mw earthquake at North Andaman triggered along NW–SE pre-existing fault with reverse fault mechanism. Macroseismic survey and GPS geodesy reveal maximum damages following NE–SW trend due to normal fault mechanism. Coulomb stress modeling for post- and inter-seismic earthquakes after the 2004 mega-earthquake show different stages of fault segment linkage at North Andaman. The present earthquake has been explained as co-shock due to asiesmic soft linkage of fault propagation.

► 5.9 Mw, June, 2010 earthquake at Andaman was recorded due to reverse faulting. ► GPS geodesy and damage pattern indicate normal faulting. ► Faults from instrument seismic record and ground truth have perpendicular relation. ► Coulomb stress modeling indicates fault linkages by subsequent earthquakes. ► Observed seismicity is explained as coshock due to aseismic slip and fault linkage.