Oleh :  Ahmad Faiz MUBAROK, Agung SETIANTO1) dan Tim PT. Asi Pudjiastuti Geosurvey 2)
1)Departmen Teknik Geologi, Fakultas Teknik, Universitas Gadjah Mada

LiDAR telah banyak dimanfaatkan untuk pemetaan skala detail, yang dapat dioptimalisasikan untuk perencanaan tata letak kota, pembangunan sarana
infrastruktur, penentuan zonasi wilayah banjir dan zonasi wilayah bencana dan juga pemetaan geologi. Namun, aplikasi LiDAR untuk geologi masih jarang
dilakukan di Indonesia, terutama yang berkitan dengan data intesity. LiDAR dapat memberikan data yang sangat detail karena resolusi spasial yang tinggi
sehingga dapat digunakan dalam interpretasi geologi. Oleh karena itu, dalam penelitian ini akan dikaji mengenai aplikasi LiDAR dalam penentuan batuan
dan kondisi geologi di daerah penelitian. read more

By: Agung SETIANTO1) and SOETAAT2)
1)Department of Geological Engineering, Faculty of Engineering, Gadjah Mada University, Indonesia
2)Department of Geodetic and Geomatics Engineering, Faculty of Engineering, Gadjah Mada University, Indonesia

In order to reduce the urgent disaster due to Mt. Bawakaraeng Caldera wall collapse, the present condition of caldera wall in detail is needed to be mapping. This caldera wall is
an inaccessible and unstable area, because the wall face is very steep, about 800 meters in height and more than 1,000 meters of the width, and located at the top of Mt.
Bawakaraeng. The caldera wall was collapsed about ten years ago and millions cubic materials, mainly sand and rock, slide down to Jeneberang River as sedimentation. read more

Indra Arifianto ⁽¹⁾, Kartika Palupi Savitri ⁽¹⁾, Muhammad Rachmat Fadhil Priana ⁽¹⁾ and Agung Setianto ⁽¹⁾

⁽¹⁾Department of Geological Enginnering, Universitas Gadjah Mada.

ABSTRACT

The research area is located in Camba-Camba Village, Batang, Jeneponto, South Sulawesi Province, Indonesia. This area is included in the the Indonesian Government ‘development acceleration program for underdeveloped regions’. This research area shows a flow ridge volcanic morphology consisting of volcanic breccia, tuffaceous sand, and laharic clay deposit from Lompobatang Volcanic Formation. The geological condition leads to a scarcity of groundwater in the area, which makes looking for a great groundwater source is challenging. On the other hand, such a groundwater source is needed to fulfil the water demands of plantation and rice field irrigation, particularly in the dry season. The geoelectric or resistivity method was used in this study to determine the location and depth of groundwater aquifers. The resistivity method used was the vertical electrical sounding (VES) “Schlumberger” method which aims to identify the variation of subsurface rocks resistivity value against depth. Through an inversion resistivity modeling, the true resistivity value in this area ranges from 0.87 to 6117 Ωm. There are five groups of subsurface rocks that could be identified based on these values, namely claystone aquiclude, shaly sand aquitard, tuffaceous sandstone aquifer, volcanic breccia aquitard-aquifuge, and lava aquifuge. Each group, respectively, showed a resistivity value of 0.87-10.63 Ωm, 12.74-22.91 Ωm, 18.83-58.25 Ωm, 62.46-159.5 Ωm, and 414-6117 Ωm. Based on the results of the correlation and modelling of these five groups, a drilling site location was set near the JPT 02 resistivity measurement point, where the model showed an aquifer at the depth of 50 meter. The presence of this aquifer was confirmed by the drilling. read more

by : Agung SETIANTO+, Tetsuro ESAKI*, Yasuhiro MITANI**,
Ibrahim DJAMALUDDIN*** and Hiro IKEMI****
(Received May 8, 2009)
Abstract
The occurrence of the surface movement is the main focus of the
study regarding to the gold & copper underground block caving mining
in Papua, Indonesia. The underground mining has brought some
environmental problems on the terrain surface such as the lowering of
the elevation followed by growing of the waste pile as the result from
the failure of the rock slope.
In this study, the surface movements due to the underground mining
were analyzed by using the aerial photogrammetry method and the
Geographic Information System (GIS) technology. The detected surface
subsidence ranging from 1.5 to 2 meter and the development of the
sedimentation area has been identified in which the maximum deposit
thickness is about 2 meter. In addition, the correlations between
extraction thicknesses over the overburden versus ground movement
have been studied in order to find out the influence of some geological
conditions in the development of the surface changing.
The surface movement induced by underground mining causes some
serious environmental impact not only above the extraction zones but
also the surrounding areas. Some environmental impacts due to the
surface movement are reviewed and discussed in this paper in order to
describe the current situation of the underground mining in Papua,
Indonesia read more