The Geological Environment of Some Ancient Caves of India: Their Optimum Utilization for Speleological Exploration and Hydrogeological Research

A study of the geological features and the speleological origin of 80 "ancient" caves of India suggests their grouping under five different geological environments and five separate speleological processes. The cave environments are portrayed on a preliminary "Cave and Karst Map of Peninsular India and the Himalaya". A possible pattern of hydrogeological and hydrological research, utilizing the caves located in the carbonate rocks of the Kurnool and Palnad areas of the State of Andhra Pradesh, is outlined, in order to get an insight into the realm of surface water-ground-water interaction and to evaluate the extent of groundwater storage and release from karstic limestone formations. The recently described, volcanogenic karst features of the Deccan basalts of Western Maharashtra, interpreted to be in a zone of lava flows covering an area of 1,20,000 sq. km also includes the locations of all the existing rock-cut caves in Maharashtra that host ancient architectural monuments and works of art. The coincidence of the two features may either be accidental, or, may have a rational explanation. Additional field checking of the photogeologically interpreted lava-Karst features in the cited special zone of Deccan basalts, in order to establish the open or filled nature of the lava karsts, may yield useful clues in this regard. The presence of sub-aerial pseudokarst, in the mantle of the boulder-talus of granite tors that cover the Closepet granites at Hampi in Karnataka and the recent finding of a 3-kilometre-long "river-cave" therein, suggest the need for additional hydrological and hydrogeological studies, for defining the extent of openness of the pseudokarst mantle and the ground-water storage potential of the pseudokarst around the proposed test-sites. These studies would need specially located river gauge-discharge sites to be established temporarily, in the two river basins and the use of ground-water data of existing open wells, in the belt of the Closepet granites extending from the Tungabhadra river valley of the Krishna river basin in the north, to the Arkavathi river valley of the Kaveri river basin in the south, located west of Bangalore. A programme of National Survey of the Cave Wealth of India is suggested, for which, the creation of a Specialist Division within the framework of the existing Federal and State geo-scientific organizations is warranted, along with the opportunities for specialized training in the mountaineering-type of skills needed for handling difficult cave exploration and mapping, both of which need a spirit of adventure for advancing scientific knowledge.