Remote sensing and VLF-EM techniques to delineate lamproites in Vattikode, Gundrapally and Marepally areas, Nalgonda district, Telangana state, India

The presence of diamonds is known in Kimberlites and lamproite pipes. The present study was carried out in Vattikode, Marepally and Gundrapally areas in the north-eastern Dharwar Craton to delineate lamproites. The remote sensing data of Liss-IV which has a 5.8 m resolution was used to identify lineaments where there could be a possibility of the occurrence of lamproite bodies. This was followed by ground geophysical surveys to delineate the presence of lamproite bodies in this area. For this purpose the Very Low-Frequency Electromagnetic Method (VLF-EM) was used to trace the shallow subsurface lamproite structures using a pseudodepth section. The VLF-EM observation data were generated along 22 profiles. The interpreted results of LISS IV and VLF-EM data correlated well to delineate lamproite pipes in the area. This was the first time in the country lamproite pipes were delineated using VLF-EM techniques.