Age of the earliest transgressive event in the Krishna-Godavari Basin, India: evidence from dinoflagellate cysts and planktonic foraminifera biostratigraphy

• Published in: Journal of Palaeogeography
• Main Authors: Ashish Kumar Mishra, Nallamuthu Malarkodi, Arun Deo Singh, Dinesh Babu, Vandana Prasad
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2020
• Subjects: Biostratigraphy; Krishna-Godavari Basin; Palaeoenvironment; Paleontology; QE701-760; Austral; Mitra; Planktonic foraminifera
• Online Access: https://doi.org/10.1186/s42501-019-0052-4; https://doaj.org/article/d73d786841d246519f5bc141ccf4caec

Abstract A combined biostratigraphic study of dinoflagellate cysts and foraminifera was carried out on Early Cretaceous subsurface well cutting sediments from well A (DNG) (2800–2746 m depth) from the Krishna-Godavari Basin, India. The last appearance datum of marker species of dinoflagellate cysts and planktonic foraminifera was considered for the construction of the biostratigraphic framework. The study shows dominance of Early Cretaceous marker dinoflagellate cysts Cassiculosphaeridia magna, Cribroperidinium perforans, Hystrichodinium voigtii, Kleithriasphaeridium eoinodes, and planktonic foraminifera Hedbergella aptiana, Hedbergella mitra, Hedbergella praelippa, Hedbergella tardita, Microhedbergella miniglobularis and Hedbergella mitra species. In addition to this, the dinoflagellate cyst data were compared with the dinoflagellate biozones of Austral and Tethyan provinces. Based on earlier micropalaeontological records from the Krishna-Godavari Basin and the present study, a latest Barremian-early Aptian age has been determined for the earliest marine transgression in the Krishna-Godavari Basin. The early marine incursion during late Barremian-earliest Aptian in the Krishna-Godavari Basin compared to Albian age in Cauvery Basin suggests the opening of east coast from north to south.