Determination of the tectonic evolution from fractures, faults, and calcite twins on the southwestern margin of the Indochina Block

摘要: In polyphase tectonic zones, integrating a study of fault and fracture with calcite twin analysis can determine the evolving paleostress magnitudes principle stress directions that affected area. This paper presents results analyses fractures, striated faults, twins collected within Khao Khwang Fold-Thrust Belt in central Thailand (SE Asia). Here we attempt to reconstruct orientation principal stresses developed during evolution this highly deformed, orogen. Tectonic data were Permian carbonates Khad Formation Saraburi Group, five successive stages are determined interpreted have before, during, after, Triassic Indosinian Orogeny. The first three predate main deformation event: stage is as pre-Indosinian N-S extensional stage, second described strike-slip compressional regime, largely perpendicular fold axes structures, while third associated an E-W phase. A further two took place or folding event correspond compression composite strike-slip/contractional latter which represent Cenozoic related India-Asia collision.