Mendhe, Vinod Atmaram and Mishra, Vivek Kumar (2021) Palaeobotanical and biomarker evidence for Early Permian (Artinskian) wildfire in the Rajmahal Basin, India. Journal of Palaeogeography.

Full text not available from this repository. (Request a copy)

Abstract

This study provides a combined analysis on the palynology, fossil charcoal and biomarkers of the subsurface coal deposits from a borehole RMB #2 drilled at the Dhulia Coal Block, Rajmahal Basin, India, in attempts to establish the chronology of sedimentation and to propose palaeobotanical as well as geochemical evidence for the occurrence of wildfires in these sediments. The palynological investigation suggests a Scheuringipollenites barakarensis palynoassemblage from the lower Barakar Formation, dated as Artinskian (Early Permian) in age. This assemblage reveals the dominance of Glossopteridales and sub-dominance of taxa belonging to Cordaitales and Coniferales. Fossil charcoal in sediments is usually recognized as a direct indicator for the occurrence of palaeo-wildfires. More data involving the anatomical features of fossil charcoal analyzed by Field Emission Scanning Electronic Microscope broaden our knowledge on Early Permian wildfires from the peninsula of India. The studied macroscopic charcoal fragments exhibit anatomical details such as homogenized cell walls, uniseriate simple and biseriate alternate pitting on tracheid walls and rays of varying heights pointing to a gymnospermous wood affinitity. The excellent preservation of charcoal fragments, shown by their large sizes and almost unabraded edges, suggests a parautochthonous origin. The embedded biomarker study performed for charcoal sediments and its characterization demonstrate the presence of n-alkanes, isoprenoids, terpenoids and aromatic compounds. A bimodal distribution pattern of n-alkanes with a Cmax at n-C25 is identified. Diterpenoids and pentacyclic terpenoids are identified, indicating the input of an early conifer vegetation and bacterial activity, respectively. The identified polyaromatic hydrocarbon (PAH) compounds, together with the charcoal fragments, clearly suggest that repeated wildfire events occurred during the deposition of these Artinskian sediments in the Rajmahal Basin.

Item Type:	Article
Uncontrolled Keywords:	Palaeo-wildfire Palynology Fossil charcoal Biomarker Barakar Formation Rajmahal Basin
Subjects:	Methane Emission and Degasification
Divisions:	UNSPECIFIED
Depositing User:	Mr. B. R. Panduranga
Date Deposited:	12 Mar 2021 07:30
Last Modified:	12 Mar 2021 09:51
URI:	http://cimfr.csircentral.net/id/eprint/2341

Actions (login required)

View Item