Palynomorphs and Oribatid Mites—From the Denwa Formation, Satpura Basin, Madhya Pradesh, India

Palynological investigation of the Denwa Formation exposed along Denwa river succession at Saptadara picnic point near village Jhirpa, Satpura Basin, Madhya Pradesh, has revealed the presence of spore-pollen, fungal remains and Oribatid mites. Here, the mites are on record for the first time. Presence of fungal remains strongly depicts the prevalence of a very humid climate with high temperature and rainfall in the region. Poor occurrence of spore-pollen restricts the age determination of the studied section;hence, its age assessment is relative. Thus, an over-view of spore-pollen along with dinocysts and insects reported earlier from the subsurface strata comprising Denwa Formation, from other two localities in the nearby area of village Anhoni, is dealt herein, and that had inferred an age—range from Carnian to Rhaetic for the palynoflora and fauna.

Palaeodepositional environment,implications of Glossopteris flora,and organic matter characteristics from the Lower Permian,Karo Open Cast Mine,East Bokaro Coalfield,Damodar Basin,India

The present study deals with the Early Permian floral diversity,palaeoenvironment,palaeoclimate and depositional setting using a multiproxy approach that includes morphotaxonomy,palynology,and organic geochemistry of Karo OCM(Open Cast Mine),East Bokaro Coalfield,Damodar Gondwana Basin,India.The Permian sediments of Peninsular India are widely regarded as fluvial,along with some marine incursions.The macroplant fossil assemblage exhibits the presence of Glossopteridales,comprising Glossopteris,Gangamopteris,and Vertebraria,as well as Coniferales,which includes Noeggerathiopsis.The palynological assemblage encompasses the dominance of the striate bisaccate pollen Faunipollenites sp.and the subdominance of the non-striate bisaccate pollen Scheuringipollenites sp.with glossopterid affinities.The megafloral and palynofloral assemblage confirms the biostratigraphical age to be Late Barakar palynoflora of Kungurian affinity.The studied morphological characteristics,including small to large Glossopteris leaves exhibiting a lanceolate shape,acute apices,and acute cuneate or tapering bases,as well as entire margins with narrower lamina and narrow meshes,suggest the existence of a dense forest with the prevalence of a warm and humid climate during their deposition.The organic geochemical characterization based on functional group and biomarker analyses reveals the diagenetic effects on organic matter.Aliphatic symmetric(~2865-2855 cm^(-1))and asymmetric stretching(~2930-2910 cm^(-1))peaks are identifiable in coal samples,whereas they are absent in carbonaceous shale.The A-factor vs.C-factor plot suggests that the kerogen type is type Ⅲ,which can generate mainly gaseous kerogen.The vitrinite reflectance studies(R_(r) av.1.1%)show increased maturity of the samples,which is supported by the n-alkane distribution pattern and the absence of hopane terpenoids.The Indian floral assemblages in contemporary of southern Gondwana continents reveal a stronger inclination/affinity with the flora of Africa than that of South America,thereby supporting the age to be of Artinskian-Kungurian.

Palaeobotanical and biomarker evidence for Early Permian(Artinskian) wildfire in the Rajmahal Basin, India

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 Cmaxat 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.