General geology and geochemistry of topsoil in Cisarua, West Java, Indonesia

The study area is located in Cisarua, West Java, Indonesia with longitude of 107° 33' 32.5" E to 107° 35' 27" E and the latitude of 6° 46‘ 14" S to 6° 48‘ 11.2" S. This research covers the preparation of updating geological maps as well as to study geochemistry of topsoil based on its elements distribution and heavy metal concentration. Geological study was carried out approximately 25km2 in and around the study area. Based on the field study carried, five volcanic rock units were identified in the study area which comprises of lapilli tuff, andesitic lahar, andesitic lava lahar, tuff breccia and pumiceous tuff. For geochemical investigation, five topsoil samples were randomly collected from different locations and are then being tested with two geochemical tests. Elements distribution for all five samples were determined and the concentration has been measured in mg/kg unit by X-Ray Fluorescence (XRF) analysis. In general, most of the elements detected are the same in all soil samples collected. However, there are some elements that did not appear in certain soil samples probably due to its low concentration. Sources of the elements distributed can be varies such as from anthropogenic activities, fertilizer usage, mining activities, the lithologies and Earth’s crust composition itself. For heavy metal study by Atomic Absorption Spectrometry (AAS) analysis, standard ranges for acceptable concentration from World Health Organization (WHO), Oregon State University (OSU) and Department of Environment Malaysia (DOE) were used to compare both the results and the standards. Six elements were selected for this analysis and from the finding, five elements has exceeded the standard value which is Cu, Fe, Mn, Zn and Co while Pb is in the range of standard concentration.