Cianjur Earthquake Caused by Movement of Cimandiri Fault
According to Indonesian Meteorology, Climatology and Geophysics Agency (BMKG), the earthquake was caused by the movement of the Cimandiri fault as quoted from Republika.
According to the Geological Engineering study at the University of Padjadjaran, the Cimandiri Fault is an old fault that was formed during stage II of orogenesis, at the end of the Middle Eocene. At that time, the sedimentary rocks of the Middle Eocene Ciletuh Formation which were formed in the Fore-Arch Basin had already been uplifted to the surface.
“This fault continues to be active, causing the formation of paleo height between the Ciletuh Valley and the Cimandiri Valley,” said one of the authors, Iyan Haryanto.
Haryanto explained that the Cimandiri Fault consists of two regional faults. The first is an ascending fault which is characterized by deformation of its rock folds which are generally upright. Furthermore, as a normal fault which is characterized by the formation of a fault escarpment with a slope of above 50 degrees. (T/ri/RE1)
Source: https://www.republika.co.id/berita/rlpez4384/mengenal-sesar-cimandiri-penyebab-gempa-cianjur
Mi’raj News Agency (MINA)