Facies Clustering in Turbidite Successions: Case Study from Andaman Flysch Group, Andaman Islands, India |
| |
Authors: | Basab Mukhopadhyay Partha Pratim Chakraborty Soumen Paul |
| |
Institution: | aGeodata and Database Division, Geological Survey of India, 27, J.L. Nehru Rd., Kolkata - 700 016, India bDepartment of Applied Geology, Indian School of Mines, Dhanbad - 826 004, India |
| |
Abstract: | Bed thickness data of two turbidite sections viz., Corbyn's Cove section, South Andaman and Kalipur section, North Andaman those belong to Oligocene Andaman Flysch Group, a forearc submarine fan system, were assessed for facies clustering employing Hurst statistics. Both the sections show Hurst phenomenon and reveal clustering in terms of thick and thin beds. Forcing behind event (bed) depositions in either of the studied sections was assessed statistically and inferred to be non-random and with cyclicities of irregular physical length. The inferred paleogeography through Hurst criteria though worked well for distal fan setting i.e., basin floor sheet sandstones of Corbyn's Cove section, its unequivocal application in proximal fan deposits remains to be tested. The mismatch in paleogeographic interpretation between Hurst test result (lobe-interlobe) and field observation (channel-levee) for the inner fan deposit is explained through differential facies stacking between fans grow in sea-level lowstand and highstand. Lower bed amalgamation, poor sand to mud ratio and subordinately present thick event deposits may be the result of active growth of Andaman Flysch fan in sea level highstand and expressed in lower Hurst K value for inner fan channel-levee association (Kalipur section) compared to many of the channel-levee deposits of lowstand fan systems observed world over. |
| |
Keywords: | Hurst statistics Andaman Flysch lobe-interlobe channel-levee sea level highstand |
本文献已被 ScienceDirect 等数据库收录! |
|