STRUKTUR GEOLOGI AREA BENCANA TANAH LONGSOR DI DESA TUMENGGAL, KECAMATAN PENGADEGAN-PURBALINGGA

Asmoro Widagdo, Sachrul Iswahyudi, Anjar Tri Laksono

Abstract


The Ligung Formation which is predominantly composed of claystone and the Kalibiuk Formation which is composed of volcanic breccias, both of which landslide simultaneously on the hillsides in the Tumenggal area, Pengadegan District, Purbalingga-Central Java. How the influence of the geological structure that has worked to compose the geological order of this area, which has an effect on the occurrence of the landslide, is the study that is revealed in this paper. Field observations of landslide locations were carried out by determining the position of the landslide, determining the type of bedrock, measuring the direction of the slope, measuring the dipping of rock layers and describing the distribution of landslides in the study area. The geological structures found in the study area are rock layers of the Ligung and Kalibiuk Formation and rock fractures/joints. Little dipping structure of the bed was observed in the field while intensive jointing was found in claystone. This structure has accelerated the weathering of claystone to form a thick soil. Andesite breccia found at the bottom of the slope has undergone intensive weathering. Rocks in the study area have a slope to the south and landslides to the north or towards the fore-slope, this is formed due to thick soil and intensive fractures/joints in the bedrock.

Keywords


claystone, breccia, structure, joint, dippin

Full Text:

PDF

References


Priyono, K.D. dan Priyono (2008), Analisis Morfometri dan Morfostruktur Lereng Kejadian Longsor Di Kecamatan Banjarmangu, Forum Geografi, Vol. 22, No. 1, hal. 72 – 84.

Rahman, A.Z. (2015), Kajian Mitigasi Bencana Tanah Longsor Di Kabupaten Banjarnegara. Jurnal Manajemen Dan Kebijakan Vol. 1, No. 1. Hal. 1-14.

Van Bemmelen (1949), The Geology of Indonesia, Vol. IA, General Geology of Indonesia and Adjacent Archipelagoes, Government Printing Office, The Hague.

Djuri, M., Samodra, H., Amin, T.C. dan Gafoer, S. (1995), Peta Geologi Lembar Purwokerto dan Tegal, Jawa, Direktorat Geologi Lingkungan, Bandung.

Widagdo, A., Jati, I.P., Waluyo, G., Purwasatriya, E.B. dan Suwardi (2014), Struktur Geologi Daerah Longsor di Gunung Pawinihan, Kabupaten Banjarnegara, Jawa Tengah. Jurnal Dinamika Rekayasa Vol. 10 No. 2 Agustus, ISSN 1858-3075, Hal. 41-44.

Hidayat, R., Sutanto, S.J. dan Munir, M.D. (2016), Kondisi Geologi dan Pola Hujan Sebagai Pemicu Longsor di Jawa Tengah Bagian Selatan Pada Juni 2016. Jurnal Teknik Hidraulik, Vol. 7, No. 2, Hal 147-146.

Susanti, P.D., Miardini, A. dan Harjadi, B. (2017), Analisis Kerentanan Tanah Longsor Sebagai Dasar Mitigasi Di Kabupaten Banjarnegara, Jurnal Penelitian Pengelolaan Daerah Aliran Sungai, Vol. 1. No.1. Hal. 49-59.

Harmoko, H.S.W. (2018), Analisis Kejadian Banjir dan longsor Di Wilayah Kabupaten Purbalingga Propinsi Jawa Tengah. Badan Meteorologi, Klimatologi Dan Geofisika Stasiun Klimatologi Kelas I Semarang.

Badan Pusat Statistik Provinsi Jawa Tengah (2020), Jumlah Curah Hujan dan Hari Hujan Provinsi Jawa Tengah Tahun 2019, diakses 13-11-2020, https://jateng.bps.go.id/statictable/2020/07/28/2049/b anyak-curah-hujan-dan-hari-hujan-menurut-bulan-diprovinsi-jawa-tengah-2019.html.

Arrisaldi, T. dan Hidayat, R. (2017), Kajian Pemanfaatan Wilayah Rawan Longsor Di Kecamatan Karangkobar, Kabupaten Banjarnegara BErdasarkan Peraturan Mentri Pekerjaan Umum No. 22/PRT/M/2007 Dengan Modifikasi. Prosiding Seminar Nasional Geografi UMS.

Susanti, P.D. dan Miardini, A. (2019), Identifikasi Karakteristik dan Faktor Pengaruh pada Berbagai Tipe Longsor, Jurnal Agritech, Vol. 39 No. 2, Hal 97107.

Priyono, K.D. dan Priyono (2008), Analisis Morfometri dan Morfostruktur Lereng Kejadian Longsor Di Kecamatan Banjarmangu, Forum Geografi, Vol. 22, No. 1, hal. 72 – 84




DOI: https://doi.org/10.31284/p.semitan.2021.1959

Refbacks

  • There are currently no refbacks.


Copyright (c) 2021 Prosiding Seminar Teknologi Kebumian dan Kelautan