ANALISIS VARIASI KECEPATAN LEMPENG TEKTONIK DI SEKITAR PALU BERDASARKAN PENGAMATAN GPS 2016-2020

• Main Author: Rangga Bachtiar, Achmad
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/61561
• Institution: Institut Teknologi Bandung

The earthquake that struck Palu-Donggala on 28 September 2018 had a magnitude of 7.5. The quake was located at -0.256 latitudes and 119.846 longitudes with a depth of 10 km. Seeing the magnitude of the resulting earthquake, it can be estimated that there will be changes in the velocity of the tectonic plates around the earthquake area. Global Positioning System (GPS) can provide a three-dimensional position and speed information as a navigation and positioning system. GPS data can be used to identify the movement of the plates beneath it. Changes in the position of the GPS point can be derived using the time function so that the velocity value is obtained at a specific time interval. This study aims to obtain the value of the velocity of the tectonic plates around Palu before and after the September 18 2018 earthquake. This study uses data time series from 14 GPS/CORS (Continuously Operating Reference System) points positions spread across Sulawesi Island and Kalimantan from 2016 to 2020. The method used in calculating the velocity of the point shift is the best fitting linear function method with parameter values obtained using the least-squares method. Based on the results obtained, the tectonic plates around Palu before the earthquake had speeds varying from -13,4 to 24 mm/year on the N-S component, - 2.3 to 26.1 mm/year on the E-W component, and -9.9 to 2.6 mm/year on the U-D component. Meanwhile, the speed of tectonic plates changed after the earthquake occurred, namely -17.7 to 48 mm/year in the N-S component, -7.6 to 35.2 mm/year for the E-W component, and -16.3 to 14 mm/year for U-D component.