CRITICAL ELEMENT SILICA SAND POTENTIAL AND DEPOSITIONAL ENVIRONMENT FOR OPTIMIZING NATURAL RESOURCES SAMBOJA AREA, KUTAI KARTANEGARA, WEST BORNEO Faiz Akbar Prihutama [1], Hedi Pangestiadi [2], Nico Andreas Nainggolan [2], Ari Soeldjana [2]
[1]Magister Geology of Hasanuddin Unversity
[2]PT Riset Sumberdaya Alam Utama
Abstract
Quartz sand is an industrial mineral that is useful in various industries such as the ceramic industry, paint industry, cement industry, glass industry, refractory brick industry, foundry industry, and as a raw material for making solar panels. The administrative research area is in Samboja District, Kutai Kartanegara Regency, East Kalimantan. Regionally stratigraphically, the research area is part of the Kutai Basin and is included in the Kampungbaru Formation and Alluvial Deposits. According to the regional geological map of the Samarinda sheet, the Kampungbaru formation consists of quartz sandstone with intercalations of clay, shale- silt and lignite, which are generally soft and easily crushed (S. Supriatna et al., 1995). The Kampungbaru Formation is an interesting research object because it contains quartz sand deposits which are quite widely distributed. The aim of this research is to determine the depositional environment, seek optimization of recovery and seek optimization of silica content in quartz sand in the Kampungbaru Formation. The depositional environment of the research area is included in the transitional lower delta plain (Horne, 1978) with sub-environments in the form of channels, levees and interdistributary bays. Sampling uses the test pit method, which is a sampling method by making a hole dug to a certain depth. Then samples are taken in two ways, namely separate samples and composite samples. The samples that have been taken are then carried out sample preparation. The sample preparation stages include washing the sample with water, drying it in an oven, washing the sample with water and a magnet, drying it in an oven, then splitting the sample into four parts. Quartz sand recovery was obtained from sizing results, where the most samples collected were in mesh 120 (0.125 mm), meaning that the dominant quartz sand recovery was medium sand grain size. Based on the results of chemical analysis, samples without washing had SiO2 levels of 93.5% - 99.4% and Fe2O3 levels of 390 - 2360 ppm. The washed samples had a SiO2 content range of 99.32% - 99.7% and Fe2O3 content of 170 - 510 ppm. Then the samples that were washed with a magnet had a SiO2 content range of 99.59% - 99.7% and Fe2O3 content of 210 - 320 ppm.
