INTERPRETASI DATA GEOLISTRIK SOUNDING UNTUK PENENTUAN KEMENERUSAN PERLAPISAN BATUBARA DI DAERAH LAHEI, KABUPATEN BARITO UTARA, PROVINSI KALIMANTAN TENGAH

ADE PUTRA WIJAYA, Drs. Imam Suyanto, M. Si.

2014 | Skripsi | GEOFISIKA

Penelitian telah dilakukan untuk menentukan kemenerusan perlapisan batubara di daerah Lahei, Kabupaten Barito Utara, Provinsi Kalimantan Tengah. Metode geolistrik sounding dimanfaatkan untuk menganalisis keberadaan batubara. Daerah penelitian terletak pada Formasi Warukin, Cekungan Barito. Nilai resistivitas digunakan untuk menentukan jenis lapis batuan. Ada 5 jenis lapis batuan dengan nilai resistivitas masing-masing, yaitu soil (bervariasi, tergantung tempat titik amat), batulempung (1,6 – 19,5 Ωm), batulanau (13,2 – 77,2 Ωm), batubara (84,8 – 108,9 Ωm), dan batupasir (141 – 1284 Ωm). Ketebalan lapisan batubara antara 2 – 3 meter, dengan kedalaman lapisan tergantung pada letak titik amat. Hal ini dikarenakan batubara pada Formasi Warukin ditafsirkan membentuk sinklin dengan penyebaran perlapisan dari arah timur laut ke barat daya. Kemiringan perlapisan pada sayap timur laut sinklin antara 6° – 8°. Dari korelasi titik sounding ditemukan 5 seam batubara dengan besar cadangan pada masing-masing seam, yaitu: seam A (8,5 juta ton), seam B (15,9 juta ton), seam C (19,5 juta ton), seam D (26,3 juta ton), seam E (35,14 juta ton).

The research has been done to determine the continuation of coal layers in Lahei area, North Barito Regency, Central Kalimantan Province. The geoelectric sounding method has been used to analyze the coal layers. Research area was in Warukin Formation, Barito Basin. Resistivity value was used to determine the types of rock layers. There are 5 types of rock layers which have its oun resistivity value; soil (it have variation where location of sounding point), claystone (1,6 – 19,5 Ωm), siltstone (13,2 – 77,2 Ωm), coal (84,8 – 108,9 Ωm), and sandstone (141 – 1284 Ωm). The thickness of coal layer between 2 – 3 meters, with the depth of layers depends on the location of sounding point. It happens because coal on Warukin Formation was defined with the shape of syncline with layers from northeast to southwest. The dip is in range of 6° – 8° on section northeast. Reasearch shows that, from the corelation of sounding points, it has been revealed that, there are 5 seams; seam A (8,5 millions ton), seam B (15,9 millions ton), seam C (19,5 millions ton), seam D (26,3 millions ton), seam E (35,14 millions ton).

Kata Kunci : Batubara, Nilai Resistivitas, Sinklin, Seam