GEOLOGY AND APPLICATION OF DIGITAL IMAGERY LANDSAT 8 FOR HYDROTHERMAL ALTERATION STUDY IN WONOSIDI REGION, TULAKAN DISTRICT, PACITAN REGENCY, EAST JAVA PROVINCE

PERDANA, ERWIN KUNDYA YOGA (2019) GEOLOGY AND APPLICATION OF DIGITAL IMAGERY LANDSAT 8 FOR HYDROTHERMAL ALTERATION STUDY IN WONOSIDI REGION, TULAKAN DISTRICT, PACITAN REGENCY, EAST JAVA PROVINCE. Other thesis, Universitas Pembangunan Nasional Veteran Yogyakarta.

[img]
Preview
Text
Cover.pdf

Download (99kB) | Preview
[img]
Preview
Text
Lembar pengesahan 2.pdf

Download (342kB) | Preview
[img]
Preview
Text
Daftar Isi.pdf

Download (109kB) | Preview
[img]
Preview
Text
Abstract.pdf

Download (171kB) | Preview

Abstract

Daerah penelitian secara administrasi berada di daerah Wonosidi dan sekitarnya, Kecamatan Tulakan, Kabupaten Pacitan, Provinsi Jawa Timur. Secara geografis daerah penelitian terletak pada koordinat 531800 mE – 537800 mE dan 9098000 mN – 9100000 mN (UTM WGS 84). Luas daerah penelitian yaitu 6 x 6 km atau 36 km2 dengan skala 1:20.000. Daerah penelitian terdiri dari bentuk asal vulkanik yang terdiri dari Perbukitan Vulkanik (V1) dan Perbukitan Intrusi (V2) dan bentuk asal struktural yang terdiri dari Perbukitan Struktural (S1) dan Lembah Struktural (S2). Pola pengaliran yang berkembang pada daerah penelitian yaitu subdendritik, fault trellis, dan radial. Stratigrafi daerah penelitian dari tua ke muda terdiri dari Satuan batupasir-kerakalan Arjosari (Oligosen Akhir-Miosen Awal), Satuan lava-andesit Mandalika (Oligosen Akhir-Miosen Awal), Satuan tuf Mandalika (Oligosen Akhir-Miosen Awal), Litodem Dasit (Miosen Awal), Litodem Andesit (Miosen Tengah), dan Satuan endapan alluvial (Holosen). Struktur geologi yang berkembang pada daerah penelitian yaitu kekar, sesar, dan lipatan (interpretasi). Kekar pada daerah penelitian ditemukan kekar gerus sebanyak 4 pasang. Sesar yang ditemukan antara lain Sesar Sumber 1, Sesar Sumber 2, Sesar Wonosidi, Sesar Ketro, Sesar Ngumbul, dan Sesar Kasihan. Struktur berupa lipatan didapatkan dari kedudukan batuan yang saling berlawanan arah kemudian dilakukan interpretasi rekonstruksi lipatan dengan sumbu lipatan berarah relatif Barat - Timur. Aplikasi Citra Digital Landsat 8 untuk studi alterasi hidrothermal menggunakan metode color composite image dan band ratio. Color composite image yang digunakan yaitu kombinasi saluran (4,3,2), (5,6,7), dan (7,5,2), sedangkan metode band ratio yang digunakan band ratio 4/2 digunakan untuk menonjolkan iron oxide dengan kandungan mineral besi yang tinggi seperti (hematite, goethite, limonite, dan jarosite) dan band ratio 6/7 digunakan untuk menonjolkan mineral lempung hidrothermal (alunit, kaolinit, illite, motnmorilonite). Hasil cek lapangan untuk interpretasi persebaran menggunakan citra digital Landsat 8 dilakukan pada 11 daerah pengamatan dan 36 lokasi pengamatan, dari 36 lokasi pengamatan didapatkan 21 (58,3%) lokasi pengamatan kurang sesuai dengan kondisi pada lapangan dan 15 (41,7%) lokasi pengamatan v sesuai dengan kondisi pada lapangan. Tingkat kesesuaian band ratio 6/7 lebih besar daripada band ratio 4/2. Ketidaksesuaian interpretasi pada citra dan kondisi pada lapangan disebabkan oleh ketidakmampuan citra digital untuk membedakan mineral alterasi dengan objek lainnya yang memiliki nilai band ratio yang relatif sama. Zona alterasi pada daerah penelitian dibagi menjadi 3 zona alterasi, yaitu zona alterasi argilik 3 zona alterasi, yaitu : zona himpunan Kaolinite ± Illite ± Kuarsa ± Pirit (Argilik), zona himpunan Klorit + Kalsit ± Pirit (Propilitik), dan zona himpunan Kuarsa + Pirit ± Kalsit ± Mineral Lempung (Silisifikasi). Tipe endapan pada daerah penelitian termasuk ke dalam Epithermal Intermediate Sulfidation, berdasarkan karakteristik tipe endapan yang ditemukan di daerah penelitian. Potensi geologi pada daerah penelitian dibagi menjadi 2 yaitu potensi positif dan potensi negatif. Potensi positif terdiri dari potensi geowisata, potensi bahan galian golongan C, dan potensi air tanah, sedangkan potensi negatif berupa gerakan massa tanah atau longsor. Kata kunci : alterasi, Landsat 8, band ratio vi GEOLOGY AND APPLICATION OF DIGITAL IMAGERY LANDSAT 8 FOR HYDROTHERMAL ALTERATION STUDY IN WONOSIDI REGION, TULAKAN DISTRICT, PACITAN REGENCY, EAST JAVA PROVINCE ERWIN KUNDYA YOGA PERDANA 111.150.082 ABSTRACT The research area location is administratively located in Wonosidi and around it, Tulakan District, Pacitan Regency, East Java Province. Geographically the research area located at 531800 mE – 537800 mE and 9098000 mN – 9100000 mN (UTM WGS 84). The large of research area is 6 x 6 km or 36 km2 with scale 1:20.000. The research area consist of four landforms, namely Volcanic Hills (V1), Intrusion Hills (V2), Structural Hills (S1) and Structural Valley (S2). The pattern of river drainage in the research area are subdendritic, fault trellis, and radial. Stratigraphy in the research area the order is start from old to young are, Arjosari’s pebbly-sandstone (Late Oligocene – Early Miocene), Mandalika’s andesite-lava (Late Oligocene – Early Miocene), Mandalika’s tuff (Late Oligocene – Early Miocene), Dacite Unit (Early Miocene), Andesite Unit (Middle Miocene), dan Alluvial Sediment (Holocene). The geological structure which develops in the research area are joint, fault, and fold. Joint in the research area found four pair of shear joint. Fault in research area are Sumber 1 fault, Sumber 2 fault, Wonosidi fault, Ketro fault, Ngumbul fault, and Kasihan fault. Fold are obtained from the opposite strike and dip of the rock, then it interpreted and reconstructed with fold axis relatively East - West. Application of digital imagery Landsat 8 for study hydrothermal alteration are color composite image and band ratio method. Color composite image that used in this study are combination band (4,3,2), (5,6,7), and (7,5,2). Band ratio method that used in this study are band ratio 4/2 used for showing iron oxide minerals (hematite, goethite, limonite, dan jarosite) and band ratio 6/7 used for showing clay minerals (alunit, kaolinit, illite, montmorilonite). The results of field check from the interpretation of distribution alteration mineral use digital imagery Landsat 8, from 36 observation location, obtained 21 (58,3%) observation location has same condition with interpretation and 15 (41,7%) not same condition with interpretation. The suitability level of band ratio 6/7 higher than band ratio 4/2. The incompatibility interpretation from digital imagery Landsat 8, is caused by a digital imager can not differentiate alteration mineral with another object that has same band ratio value. The alteration zone of the research area is divided into three zone are : zone with mineral Kaolinite ± Illite ± Quartz ± Pyrite (Argillic), zone with mineral Chlorite + Calcite ± Pyrite (Propylitic), dan zona with mineral Quartz + vii Pyrite ± Calcite ± Clay Mineral (Silisification). Type of mineral deposit in the research area is Epithermal Intermediate Sulfidation. Geology potential of the research area divide into two, that are positive potential and negative potential. The positive potential are geotourism, quarry minerals class C, and groundwater, while the negative potential is mass wasting or landsalides. Keywords : alteration, Landsat 8, band ratio

Item Type: Thesis (Other)
Subjects: Q Science > QE Geology
Divisions: Faculty of Engineering, Science and Mathematics > School of Engineering Sciences
Depositing User: Sarimin Sarimin
Date Deposited: 27 Aug 2019 03:10
Last Modified: 27 Aug 2019 03:10
URI: http://eprints.upnyk.ac.id/id/eprint/20825

Actions (login required)

View Item View Item