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ABSTRAK PENELITIAN POST DOCTORAL TAHUN 2013 Lembaga Penelitian dan Pengabdian Masyarakat (LP2M) Universitas Hasanuddin Kampus Unhas Tamalanrea Jln. Perintis Kemerdekaan KM. 10 Makassar Telp. : 0411 587032, , 582500, 588888 Fax.(0411) 587032, 584024 Website : http://www.unhas.ac.id/lppm email : [email protected] Muhammad Altin Massinai, Lanti, Makharani Prodi Geofisika Unhas Abstrak Penelitian ini menggunakan teknik geolistrik tahanan jenis berkonfigurasi Werner untuk mengetahui pola penyebaran vertikal lapisan batuan di Daerah Aliran Sungai (DAS) Jenelata. Geologi daerah tersebut didominasi batuan plutonik dan rempah-rempah gunungapi. DAS Jenelata merupakan tempat aliran material letusan Gunungapi purba Sapaya. Nilai tahanan-jenis yang diperoleh dari 4 lintasan dengan masing-masing panjang 150 meter menunjukkan nilai tahanan jenis rata-rata di DAS Jenelata sekitar 5 – 2000 Ωm. Nilai tahanan jenis ini dapat dikelompokkan menjadi 2 bagian yaitu 5 – 300 Ωm dan 301 – 2000 Ωm. Hasil yang terakhir ini menunjukkan nilai tahanan jenis batuan plutonik. Di sekitar hilir DAS Jenelata nilai tahanan jenis relatif rendah, yaitu dibawah 300 Ωm. Nilai ini menandakan bahwa di hilir DAS mengendap batuan yang telah mengalami pelapukan. Kata kunci: Gunung api Sapaya, Tahanan Jenis, Batuan Plutonik. Abstract This is a reasearch on the geoelectric resistivity role determining to the pattern of distributionof vertical resistivity value in the rock layer of the Jenelata watershead by considering the geological condition of the area as the background. The local geology is dominated plutonic rocks and pyroclasic volcanic. Jenelata watershed is the accumulation of eruption material from Sapaya volcano. The Resistivity material from several types of rock settling needs to be identified by using the geoelectric geophysical studies. Geoelectrical resistivity method used in this study aims to map the vertical layers of rock in the upstream and downstream of Jenelata watershed. The results of the 4 tracks with each length of 150 meters shows that resistivity values in the upstream of Jenelata watershed is relatively high at around 5 - 2000 ohmmeter. This price indicates the value can be grouped into two part, 5 – 300 ohmmeter and 301 – 2000 ohmmeter latter result of plutonic rock of resistivity type. Around the downstream watershed of Jeneberang, resistivity value is relatively low, ie below 300 ohmmeter. This value indicates that in the downstream of watershed sediment rocks have experienced weathering. Keywords:, Sapaya volcano, resistivity type, plutonic rocks .
