ANALISIS PERSEBARAN AIR TANAH DAN IDENTIFIKASI LAPISAN DI BAWAH PERMUKAAN TUK SIBEDUG MENGGUNAKAN METODE GEOLISTRIK KONFIGURASI DIPOLE-DIPOLE

Analysis of groundwater distribution and identification of subsurface Tuk Sibedug has been carried out using the Dipole-dipole configuration geoelectric method. Measurements are made on 3 tracks, with a space between electrodes (20 and 40) meters. The tool used is Syscal Jr Switch-48. The software used is Global Mapper13, Surfer10, Res2dinv3, and Arcgis 10.3. The results of this study showed 2D cross section indicating the subsurface conditions of the study area based on resistivity values. Determination of rock types based on the resistivity value of the measurement results correlated with geological conditions. Layers under the surface of Tuk Sibedug are interpreted as clay, sandstone, and breccia. The clay has the smallest resistivity value (3.80 s.d. 9.18) Ohm-meter, sandstone (9,18 s.d. 34,40) Ohm-meter, and breccia (34,40 s.d. 83,10) Ohm-meter. Ground water is stored in sandstone. The subsurface layer 1 has a depressed aquifer system. Distressed aquifers are confined between breccia and clay stones, so that they have a natural pressure that pushes ground water up on the surface of the Tuk Sibedug. Faulting in the rock layering structure becomes a gap for ground water to continue to drain water. The hydrogeological system in the Yogyakarta-Sleman Groundwater Basin is the Merapi Aquifer System (SAM), thus making the water reserves in Tuk Sibedug very abundant