Regional Geology

The Sihayo-Pungkut CoW is located in the Barisan Mountains of North Sumatra Province on the island of Sumatra and at the western end of the +7,000 km long Sunda-Banda magmatic arc.

The dextral-transcurrent Trans-Sumatran Fault Zone (TSFZ), running for the entire length of Sumatra along the Barisan mountain range, was formed by the oblique subduction of the Indo-Australian oceanic plate beneath the Eurasian continental plate in the Sumatran segment of the Sunda-Banda arc commencing in the Neogene period (mid-late Tertiary). The TSFZ is a focus for major regional faulting (thrust and strike-slip), uplift and erosion, pull-apart basin development and sedimentation, volcanism and geothermal activity in Sumatra.