Bulletin of the Geological Society of Malaysia, Volume 20, August 1986, pp. 59 – 71
Department of Geology, Faculty of Science, Chulalongkorn University, Thailand
Abstract: The Sri Racha area in southwestern Chonburi province is underlain by late Palaeozoic sedimentary or metasedimentary rocks, Triassic granites, and Quaternary sediments. The late Palaeozoic rocks occupy 30 percent of the western portion of the area while granites dominate the eastern portion and underlie approximately 20 percent of the area.
The late Palaeozoic rocks are believed to be of Permian and Carboniferous age and possibly as old as Devonian. The Carboniferous rocks are lowgrade metamorphics consisting of both foliated and non-foliated varieties. They are divided into 3 distinctive units, in order of descending age, namely interbedded schist and quartzite, quartzite, and metacarbonate. After correction for possible thickening due to folding, the overall thickness of these rocks does not exceed 1,000 m. The Permian rocks are rather limited in distribution, comprising less than 50 m of clastic and non-clastic rocks. Foraminifera found in the limestone indicate a Permian age.
The late Palaeozoic sedimentary rocks have been folded. The fold is interpreted to be a westerly dipping overturned anticline. It is located principally in the western and central portions of the area. In the northeastern portion, the area is intruded by fine to coarse-grained granites.