Penentuan Zona Kerentanan Longsor Berdasarkan Karakteristik Geologi dan Alterasi Batuan

Anastasia Dewi Titisari; Hitznaiti Zaidini' Khul Husna; Ilham Dharmawan Putra; I Gde Budi Indrawan

doi:10.22146/jpkm.35935

Penentuan Zona Kerentanan Longsor Berdasarkan Karakteristik Geologi dan Alterasi Batuan

https://doi.org/10.22146/jpkm.35935

Anastasia Dewi Titisari^(1*), Hitznaiti Zaidini' Khul Husna⁽²⁾, Ilham Dharmawan Putra⁽³⁾, I Gde Budi Indrawan⁽⁴⁾

(1) Departemen Teknik Geologi, Fakultas Teknik, Universitas Gadjah Mada, Senolowo, Sinduadi, Mlati, Sleman Regency, Special Region of Yogyakarta 55284, Indonesia.
(2) Departemen Teknik Geologi, Fakultas Teknik, Universitas Gadjah Mada, Senolowo, Sinduadi, Mlati, Sleman Regency, Special Region of Yogyakarta 55284, Indonesia.
(3) Departemen Teknik Geologi, Fakultas Teknik, Universitas Gadjah Mada, Senolowo, Sinduadi, Mlati, Sleman Regency, Special Region of Yogyakarta 55284, Indonesia.
(4) Departemen Teknik Geologi, Fakultas Teknik, Universitas Gadjah Mada, Senolowo, Sinduadi, Mlati, Sleman Regency, Special Region of Yogyakarta 55284, Indonesia.
(*) Corresponding Author

Abstract

ABSTRACT

Landslide is one of the most frequent disasters in Indonesia. The occurrence of landslides is heavily controlled by geological conditions especially in areas with composed by altered rocks. Hargotirto Village, Kokap District, Kulon Progo Regency, DIY is composed by altered rocks so that many landslides occur.It is necessary, thereforeto determine the landslide susceptibility zone based on the geological characteristics and rock alteration in the area as one of disaster mitigation efforts to reduce the risk of landslide disaster. The research method used is data collection in the field such as inclination data of slope, geological condition, and land cover; and laboratory analysis such as petrographic analysis, XRD (X-Ray Diffraction) analysis, and rock geochemical analysis using ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectroscopy).The collected data are used as parameters for landslide zonation determination using Analytical Hierarchy Process (AHP) method.The results showed that the lithology of the research area is andesite and porphyry diorite with alteration type of argillic and propylitic alteration. Their intensity are categorized as low to moderate alteration.Based on these conditions can be categorized into4 levels of landslide susceptibility namely the very high landslide susceptibility that dominates 35% of research areas in the north and northwest; the high landslide susceptibility of 20% spreads over the center of the study area; the moderate landslide susceptibility of 20% distributed in the center southernof the study area; and the low landslide susceptibility of 25% spread over the southern part of the study area.Therefore, residents who live in the area are advised to always be alert to the possibility of landslide because it is included in the zone of very high and high landslide susceptibility.

Keywords: argillic alteration; Hargotirto; landslide susceptibility; prophyllitic alteration

Keywords

argillic alteration; Hargotirto; landslide susceptibility; prophyllitic alteration

Full Text:

PDF

References

Badan Nasional Penanggulangan Bencana. (2017). Data dan Informasi Bencana Indonesia. Retrieved from http://dibi.bnpb.go.id

Badan Penanggulaangan Bencana Daerah Provinsi DIY. (2017). Peta Bencana Tanah Longsor. Retrieved from http://

bpbd.jogjaprov.go.id

Barianto, D. H., Harijoko, A., & Watanabe, K. (2009). The Tertiary Volcanic Rocks Distribution In Yogyakarta And Its Vicinity, Indonesia. Earth Science International Conference Journal, Manila, pp. 5.

Bemmelen, R. W. V. (1949). The Geology of Indonesia 1. Amsterdam: Government Printing Office The Hauge.

Direktorat Jendral Penataaan Ruang. (2007). Pedoman Penataan Ruang di Kawasan Rawan Bencana Longsor. Departemen Pekerjaan Umum.

Harjanto, A. (2010). Alterasi Akibat Proses Hidrotermal di Daerah Kulon Progo dan Sekitarnya Daerah Istimewa Yogyakarta. JIK TekMin, September-Desember 2010, Vol. 23(3).

Harjanto, A. (2011) Petrologi dan Geokimia Batuan Volkanik di Daerah Kulon Progo dan Sekitarnya Daerah Istimewa Yogyakarta. Jurnal Ilmiah MTG, Vol.4, No.1.

Husna, H. Z. K. (2018). Geologi dan Alterasi Hidrotermal untuk Penentuan Zona Kerentanan Longsor di Desa Hargotirto dan Sekitarnya, Kecamatan Kokap, Kabupaten Kulon Progo, Provinsi Daerah Istimewa Yogyakarta. Skripsi. Departemen Teknik Geologi, Fakultas Teknik, Universitas Gadjah Mada (unpublished)

Large, R., R., Gemmel, J. B., Paulic H., & Houston, D. L. (2001). The Alteration Box Plot: A Simple Approach to Understanding the Relationship between Alteration Mineralogy and Lithogeochemistry Associated with Volcanic-Hosted Massive Sulfide Deposits. Economic Geology, Vol. 96, 957—971.

Pramumijoyo, P. (2017). Geologi, Geokimia, dan Karakteristik Fluida Hidrotermal pada Endaparan Epitermal Sulfidasi Rendah di Daerah Sangon, Kokap, Daerah Istimewa Yogyakarta. Yogyakarta: Universitas Gadjah Mada Press.

Rahardjo, Sukandarrumidi, & Rosidi. (1995). Peta Geologi Lembar Yogyakarta Jawa. Pusat Penelitian dan Pengembangan Geologi.

Saaty, T.L. (2008). Decision Making with the Analytic Hierarchy Process. Int, J. Services Sciences, I, 83—97.

DOI: https://doi.org/10.22146/jpkm.35935