INTERPRETATION OF THE SUBSURFACE AND THE ANALYSIS OF THE CAPACITIVE PROPERTIES UNDER THE SURFACE TO REVIEW THE EFFECTIVENESS OF SIGNAL ON THE SOUTH CIVIL ENGINEERING ITB GROUND FIELD WITH GEOELECTRIC 1D

• Main Author: Timothy Yohanes Turnip, Badia
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/49112
• Institution: Institut Teknologi Bandung

Under the surface of the liquid Earth a group of various soils that have its own conductive properties. Geoelectric is a method in geophysical that learns the nature of electric Kong in the earth and how to detect it on the surface of the Earth. As for this research aims to determine the resistivity value of the field of South Civil engineering ITB and the lower layer of the surface, determining the effectiveness of the use of AC signal through the relationship between the value of AC signal impedance and the resistance of the DC signal, determine the distribution of capacitance on the subsurface of the Southern Civil Engineering ITB. The acquisition of the research data was conducted on Saturday, 22 February 2020 located at the South Civil engineering field ITB at 10.00 – 13.00 WIB. Referring to the coordinates data earth.google.com, the South Civil engineering field ITB which is the location of data acquisition is at the coordinates S6 53 36-E107 36 32 namely S6 53 34 – E 107 36 35. The raw data obtained when data acquisition is offset voltage values, rated voltage, measured current for each electrode spacing distance. As for the processing of data carried out ie the underground layer using resistivity data, comparing the impedance value of AC signal at the Sell frequency and DC signal resistance, reviewing the capacitance distribution of each depth. After the research, it is interpreted that the subsurface in the field of civil engineering South ITB is a layer of tufa shell that serves as aquifer, with a high water content so that it can affect the value of capacitance is likely to be high as well. The difference between AC impedance and DC resistance is also obtained, resulting in a percentage of difference that is in fact below 10% for the barrier value ranging from 0, 1 ? to 11 ?. The capacitance value obtained from 0001 Farad was 11,811 Farad, with the deeper distribution being more and more likely the larger the capacitive layer. DC signal method is quite quality on the measurements in the South civil field ITB with the consideration that the differences from the AC and DC values are quite small, so that the capacitive properties of ground civil engineering field is not too much affect the performance of the signal used. With the capacitance distribution data, it is also advisable to utilize the most capacitive layer at a depth range of 3 – 4 meters below the surface as the transmitter zone.