The identification of tectonic regimes based on mechanical properties derived from log data in Nangroe Aceh Darussalam

Tectonic stresses can be derived from mechanical rock properties at a certain depth below the surface. Every inter-granular relationship occasionally exhibits a dynamic range of behavior, assumed to instigate rock deformation. The purpose of this study is to determine any potential stresses by mechanical properties which is derived from log data. The research area is situated in the NW-SE structural orientation, parallel to the subduction zone, and it is located within northern part of Sumatra. This zone is near of the convergent plate which is known to collide with strain partitions to produce two main structural components. The first appears perpendicular to the trench, manifested by folds and ascending faults on the accretionary prism, in contrast, the second accommodates the oblique convergent strike-slip fault and it is parallel to the trench. Furthermore, great tectonic strength generated a major earthquake of 9.0 Mw and 8.6 Mw in Sumatra-Andaman (2004) and Nias Islands (2005), respectively. The results of mechanical properties derived from well data, which is validated by magneto-telluric and gravity data, points out that this area had been undergone a transition of strike-slip fault regime to thrust fault regime or transpressional regime. It can be seen in moment tensors changing at entire depths in the back-arc basin, which is strongly influenced by Semangko Fault.