DEPOSITIONAL SYSTEM OF AN OPEN COAST TIDALFLAT - AN EXAMPLE FROM PALEOPROTEROZOIC VEMPALLE FORMATION, CUDDAPAH BASIN, INDIA

作者：Panja Madhumita; Chakrabarti Gopal^*; Shome Debasish

来源：Carpathian Journal of Earth and Environmental Sciences, 2017, 12(1): 269-282.

• Facies
• Tidalflat
• Palaeoproterozoic
• Vempalle
• Stromatolites

The sedimentological study in the Paleoproterozoic Vempalle Formation of the Cuddapah Basin, in and around Gandi, (14 degrees 20'2.51"N, 78 degrees 28'52.96"E), Vempalle town (14 degrees 21'27.74"N, 78 degrees 28'16.46"E; 14 degrees 21'28.86"N, 78 degrees 27'46.63"E) and Nandemandalam village (14 degrees 24'33.84"N, 78 degrees 31'39.22"E) reveals three major facies associations viz. supratidal facies association consisting of cross-bedded gritty quartzite facies, heterolithic facies and laminate facies; intertidal facies association consisting of red shale, lime-mudstone, ooliticgrainstone, and domalstromatolite facies whereas deeper intertidal environments are locally dominated by columnar stromatolite, massive dolomite and intraformational carbonate conglomerate and subtidal facies association consisting of conical stromatolite facies. Facies association and associated synsedimentary deformation structures, stromatolite morphology and microfabric clearly demonstrate that the Vempalle Formation in the study area was deposited in an open coast tidalflat having mixed influence of waves and tides, the storm dominated depositional processes marked by accretionary deposition of HCS and the scarce influence of tides in depositing sand.

• 出版日期2017-2