Analysis and Zonation of Land Vulnerability Areas in Pekon Karangrejo Ulubelu Tanggamus Using Microzonation Method

Eko Rananda; Lintang Prabowo; Arief Putih Prabowo; Syamsurijal Rasimeng; Ida Bagus Suananda Yogi

doi:10.36435/jgf.v18i1.420

Eko Rananda Departement Of Geophysical Engineering, Faculty Of Engineering, University Of Lampung
Lintang Prabowo Departement Of Geophysical Engineering, Faculty Of Engineering, University Of Lampung
Arief Putih Prabowo Departement Of Geophysical Engineering, Faculty Of Engineering, University Of Lampung
Syamsurijal Rasimeng Departement Of Geophysical Engineering, Faculty Of Engineering, University Of Lampung
Ida Bagus Suananda Yogi Departement Of Geophysical Engineering, Faculty Of Engineering, University Of Lampung

DOI: http://dx.doi.org/10.36435/jgf.v18i1.420

Keywords

microzonation, dominant frequency, dominant period, Vs30 and amplification

Abstract

Abstract.Ulubelu Tanggamus is an area that have geothermal energy potential. This region consists of a geological structure in the form of graben and reverse fault formed between Mount Rendingan and Mount Kukusan. Identifications that can be done include surveys to map soil characteristics in shaking responses using microzonation methods. This study aims to analyze the values of dominant frequency, dominant period, Vs₃₀ and amplification. The stages of the research carried out are processing data to obtain dominant frequency, calculating the value of the dominant period, calculating the value of Vs₃₀ and the amplification value, and making a map of the soil vulnerability of the UlubeluTanggamus area. Based on the distribution of the dominant frequency values, the UlubeluTanggamus geothermal area is dominated by a dominant Frequency (F₀) >0.5Hz which is expected to be a very thick surface thickness of sediments more than 30m. The distribution of the dominant period value obtained is (T₀)>1 where the character of the sedimentary rock type is very soft consisting of alluvial material formed from sedimentation of deltas, top soil, and mud. The distribution of the Vs₃₀ value is dominated by the value of 100 <Vs₃₀<200 and obtains an amplification value of 2<A₀<6 times where the area is an area with a moderate risk category to the danger of soil vulnerability.

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