Comparison of Transient Electromagnetic and DC Resistivity for aquifer layer in Cisarua, Bandung Barat Regency

Geophysical investigation is conducted to study groundwater in water absorption region for Bandung Basin hydrology system. It is placed in Cisarua, Bandung Barat Regency, which composed of old and young volcanic products. Resistivity based geophysical methods are used, Geoelectrical Resistivity and Transient Electromagnetic (TEM). TEM measurement are usingused long grounded wire configuration with transmitter length 500 m and current 13 A. Geoelectrical Resistivity are usingused Wenner-Schlumberger configuration with maximum array distance 560 m. TEM Measurement recorded high amount of cultural noise since it is was near to cellular and radio transmitters. After filtering and inversion process, low resistivity zone (35–40 Ωm) are were detected at elevation 1185–1075 m. Deeper low resistivity zone assumed to have high water saturation are were also detected at 210 – -290m. This resultsed are were correspond with Geoelectrical Resistivity measurement which detecteddetect low resistivity zone at 1185 – 1140 m, with lowest resistivity value was 32 Ωm. In Geoelectrical Resistivity Section, we can could see that the low resistivity zone is was continuous from north to south. From both methods, the low resistivity zone are were interpreted as shallow unconfined aquifer serve as water source for domestic well in study zone.