Near-Surface Geophysics Application for Archaeology, Coal Mining and Road Landslide in East Kalimantan Province of Indonesia

Abstract

The study presents the application of Near-Surface Geophysics to Archaeology, Road Landslide and Coal Mining in East Kalimantan province of Indonesia. The province covers mostly by tertiary sedimentary rocks of Kutai Basin from Eocene to Recent epoch. The lithology is mainly sandstones, siltstones, mudstones, shales, and alluvial sediment. The main goal of this study is to imaging the structure and physical properties of soil in Muara Kaman Archaeological site, National Road Landslide and Coal mining nearby Samarinda. Several of the study conducted in the reactivated of old landslide that has been reconstructed for road maintenance. Integration of geological and geophysical surface and subsurface data-sets has resulted in interpretation of the slip surface characteristics as a requisite in detail engineering design for construction. The resistivity method is one of recommended methods by department of public works and public housing (ie.PUPR) for investigation of the road landslide. The measurement of electrical resistivity tomography (ERT) has been conducted in nine different locations of road landslide along national road from Samarinda to Berau in East Kalimantan. The results shows that the slip surface occurred in the contact of the clay with resistivity < 100 ohm.m and the underlying rocks. The interpretation that constrained with the borehole showing the slip surface varies between 2-10 m. It is inferred that steeply dipping structure in adjoining with hydrogeological conditions and lithostratigraphics composition of the soil with intense and prolonged rainfall are the main triggers for the development of road landslide.