THE RELATIONSHIP OF GEOLOGICAL CONDITIONS BETWEEN THE NGARAI SIANOK - MANINJAU GEOPARK AND THE SILOKEK GEOPARK Fachri Vanrenov (a*), Mirzam Abdurrachman (a), Idham Andri Kurniawan (a), Abdillah Baraas (a), Firman Sauqi Nur Sabila (a), Dian Hardiansyah (a), Fakhri Irsyad Anwar (a), Muhammad Bahrun Najah (a), Muhammad Hafizh (a)
Faculty of Earth Sciences and Technology, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia
*fachrivanrenov96[at]gmail.com
Abstract
Ngarai Sianok - Maninjau Geopark and Silokek Geopark are one of the national geoparks in West Sumatra Province, as it is known that this Sumatran fault extends from the Bay in Lampung to the northern part of Aceh, is a dextral slip fault and has undergone a 25-30 km. Formed as a result of the subduction of the Indo-Australian Plate which moves relative to the North under the Eurasian Plate, thus forming an oblique mechanism. One of the relationships between the Great Sumatran Fault is by looking at evidence from the geosites in the Sianok - Maninjau Geopark and the Silokek Geopark. What is visible is the formation of the Ngarai Sianok (Sianok Valley), which is the influence of a shear fault and creates a pull-apart basin negative flower structure, this section is part of the Sianok segment.
Apart from the formation process, there is also the presence of a geosite which is quite interesting from the main presence in the form of the Sianok Gorge with turbidite deposits from the destruction of Mount Sitinjau which now creates a caldera that contains a meteoric water lake which is now called Lake Maninjau. Until it is old and is part of the basement in the Silokek Geopark area which looks like old granite. As a related link for the geotourism activities of these two geoparks with the petrographic, rock geochemical, and geomorphological methods which are very fascinating from the history of geology which explains the processes that occurred from the oldest perm age in the Silokek Geopark section, to the youngest process which is in the Sianok Geopark section.
Keywords: Ngarai Sianok, Maninjau, Silokek, Geopark, Great Sumatran Fault, UNESCO
