DECCAN VOLCANIC OF MALWA, STRATIGRAPHY AND CORRELATION OF BASALTIC LAVA FLOWS USING MEGACRYST BEARING HORIZON AS TOOL, PARTS OF WESTERN M.P. INDIA

A review of earlier studies of the Deccan Trap occurrences of parts of Ratlam, Mandsaur, Jhabua, Dhar, Khargone, Indore, Ujjain and Shajapur districts of Madhya Pradesh, India was carried out of the area falling between latitudes 220 0000 to 2400000N and longitudes 7400000 to 7600000 in Survey of India Quadrangle sheet Nos. 46I, 46J, 46M and 46N.The main objectives of the study were to synthesize the data on the Deccan Trap basaltic lava flows , their types ,their diagnostic characteristics with special emphasis on delineating and identifying the various megacryst horizons , their levels with specific elevation above m.s.l. to build up the litho-stratigraphy for regional correlation. Broadly the area exhibits the Proterozoic Aravalli Supergroup, the Cretaceous, Bagh and Lameta Groups and the Deccan basaltic lava flows with intruded dykes and sills. The Aravalli Supergroup is represented by the Udaipur, Lunavada and Champaner Groups. The Udaipur Group consists mainly of hornblende gneiss, marble and calc-silicate, carbonaceous phyllites and chlorite schist. The Lunavada Group comprises dolomitic limestone (Phosphate bearing), quartzite, muscovite quartzite, quartz muscovite schist, feldspathised quartzite, gneissic feldspathic rock and biotitic gneiss. The Champaner Group is represented by dolomite, phyllite, slates and basic intrusives. The Aravalli Super group of rocks is also intruded by serpentinite, pyroxinite, granite and basic rocks. The Aravalli Supergroup of rocks is unconformably overlain by Cretaceous marine sedimentary deposits of Bagh Group. It includes Lower arenaceous and Upper calcareous units and occurs as discontinuous outcrops.