Supriyadi, Andya Satya Purnomo Putro, Khumaedi, Cherly Salawane
The seawater intrusion into the shallow groundwater in Tanah Mas residential North Semarang was predict by 3D resistivity imaging and precipitation data. The seawater intrusion was investigated by resistivity survey which generated by multi-electrode system with sixteen electrodes configuration. Analysis of rainfall data will show how much the influence of groundwater pressure from rainfall in the study area to the saltwater interface. The result of precipitation data indicates very low medium rainfall, with 0.6 mm for October 126.1 mm for November. In October, the coastal aquifer will be so pressed by salt water that sea water intrusion penetrates into freshwater areas. In November, the coastal aquifers are recharged by precipitation and replenished water flowing to the sea then prevent saltwater from encroaching into the area of freshwater. The resistivity survey detected the presence of seawater intrusion because it has a small resistivity range between 0.120-0.980 Ωm at a depth about 13.5 m to 26.9 m. 3D resistivity images show the distribution of seawater intrusion in the Tanah Mas area in horizontal and vertical direction. The distribution of seawater intrusion has reached northern, eastern and southern part of Tanah Mas area. © Int. J. of GEOMATE. All rights reserved, including the making of copies unless permission is obtained from the copyright proprietors.
Faculty of Mathematics and Natural Sciences, Universitas Negeri Semarang, Indonesia; Universitas Negeri Semarang, Indonesia
