SPELEOTHEM DEPOSITS DEVELOPED IN CAVES AND TUNNELS OF DECCAN-TRAP BASALTS, MAHARASHTRA, INDIA

Calcite speleothems composed of stalactites of about 1/2 cm to 1 1/2 c m in length and stalagmites of approximately 15 cm are found in the an cient caves and tunnels in the Deccan-Trap basalts. Thin-section analy sis reveals that they dominantly consist of clay-rich micrite, microsp ar, or sparry calcite layers. These layers are either finely laminated and planar, or irregular and exhibit sutured contacts. Percolating wa ters dissolve calcium carbonate along joints or fractures in the basal ts. Speleothem precipitation, initiated on the roof of the caves as a result of the degassing of CO2, led to a decrease in the solubility of CaCO3, and hence to calcium-carbonate saturation.