PENCITRAAN RESISTIVITAS UNTUK IDENTIFIKASI BENDA-BENDA MEGALITIK DALAM TANAH DAERAH SITUS POKEKEA, POSO, SULAWESI TENGAH; RESISTIVITY IMAGING FOR IDENTIFICATION OF MEGALITHIC OBJECTS IN THE GROUND REGIONAL SITE POKEKEA, POSO, CENTRAL SULAWESI

Maskur, Suparta, Gede Bayu

2015 | Disertasi | FMIPA UGM

Research on resistivity imaging for identification of megalitihic objects in the ground regional site pokekea, Poso, central Sulawesi has been conducted. In this research, the geoelectric resistivity was measured based on Wenner configuration, with stretch length of 55 meters and electrode spacing of 1 meter. Measurements were taken around megalithic objects that was located on the surface. From the measurement data, apparent resistivity values was obtained. Two dimension cross-sectional images were obtained from the processing data using RES2DINV software, whereas 2D imaging analysis was used ImageJ software. Image analysis measurements included measuring 2D image coordinates which gave an overview of distribution and position of the presence that contained megalithic objects in subsurface. The results showed that this method was able to identification the presence of megalithic objects contained in subsurface. Based on a two-dimensional image analysis using RES2DINV and ImageJ from measurement results of the four track in spaced 1 meter, there were megalithic relics buried beneath the soil surface. Physically, based on resistivity image analysis, the variation of rock resistivity values that was characterized were quite high compared to the other rocks that has constituent resistivity values ranged between 1000-3500 ?m. In line profile analysis of megalithic objects presence, that were indicated by the correlation of the graph distance (meters) with a gray degree (gray level) obtained gray level differences were very clear between the dark and light areas. From the four stretch measurement it showed that the lowest degree (minimum) of gray had similarity value each other, which was defined that in those area there were anomalies representing the existence of megalithic objects.

Kata Kunci : imaging; megalithic; geoelectric; resistivity; distribution