Abstract:
Sri Lanka consists of four major lithotectonic divisions. And nine-tenths of the island is underlain by Precambrian crystalline rocks, the rest being made up mainly of Miocene Limestone and Quaternary deposits along the north-western and northern regions. Principally, mineral resources are highly confined to the Highland/Vijayan boundary zone. One of the main mineral resources along this zone is vein quartz, predominantly south and southeastern part of the island. Mahagama and Randeniya are two major occurrences which were investigated in detail including ID resistivity survey and 2D resistivity profiling by the Geological Survey and Mines Bureau (GSMB). Generally, vein quartz boulders are confined to elongated ridges along strike direction displaying a weather resistant nature. That is a key to delineate vein quartz from its associated bedrock. Otherwise, it is very difficult to isolate vein quartz from background material, particularly from the bedrock, due similar resistivity ranges.
