Application of microseismic methods for identification of ground movement potential in Cemara sub-village, Sukorejo village, Gunungpati Semarang

Abstract

Based on data of landslide from Regional Disaster Mitigation Board (BPBD), Sukorejo village is one of three urban villages in Gunungpati which has a high potential possibility for disaster, particularly landslide. One of the areas in Sukorejo Village that frequently sustains of land movement is Kampung Cemara. On April 23, 2018 in Kampung Cemara, a landslide occurred which caused detrimental damage to buildings. Several other accidents signified ground movement resulting cracks in the land surface. The high level of losses is not only induced by the magnitude of the disaster, but also due to inadequate information related to the potential for disasters and conditions in the area, that it decreases public awareness of the environment. That is the main reason for this micro seismic research. Micro seismic is a geophysical method which employ to determine the ground motion potency through the subsurface layer characteristics by calculating the value of Ground Shear Strain (GSS). The data processing is using the HVSR method. The value was ranged from 4.54 × 10−3 to 1.59 × 10−2. The result represents that Kampung Cemara is considerably potential to undergo land movements with plastic-elastic soil properties and ground motion phenomena that can effect vibration and cracks in surface land and habitation.