Detection of hidden faults beneath Khlong Marui fault zone using seismic reflection and 2-D electrical imaging

Abstract

The Khlong Marui fault zone is a major fault located in the southern part of Thailand extending across the peninsula. In spite of the available information on fault segments and tectonic activity associated with faulting, the local scale fault characteristics are currently barely known and are often difficult to detect in areas where surface displacement has not occurred. The present geological field investigation reveals that the study area in Surat Thani province possibly contains more minor faults where the shallow faulting is evident. To detect fault locations and to study fault characteristics, seismic reflection analysis and 2-D electrical imaging were applied along the three survey lines as a case study. After data processing, an interpretation was proposed based on the correlation of geophysical results with the geological information. Discontinuities in the main horizons in seismic sections and correlatable zones in resistivity imaging indicate that faulting is present in a Permian-Carboniferous unit and may extend to the shallow subsurface in Quaternary sediments.