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A palynological analysis of borehole RB-1, Raniganj Coalfield, Damodar Basin, has been presented here. Based on the quantitative analysis of the spores and pollen grains of the productive samples, three palynoassemblages have been identified: Palynoassemblage-I demarcated at a depth between 335.00 and 284.00 m is distinguished by the dominance of nonstriate bisaccate pollen Scheuringipollenites and subdominance of striate bisaccate pollen Faunipollenites suggestive of an early Permian (Artinskian) age; Palynoassemblage-II identified at a depth between 278.00 and 32.00 m shows the prominence of striate bisaccate mainly Faunipollenites, Striatopodocarpites and subdominance of Scheuringipollenites signifies late early Permian (Kungurian) age, and the youngest Palynoassemblage-III marked at a depth between 30.00 and 03.00 m contains dominance of striate disaccates pollen, viz., Striatopodocarpites, Crescentipollenites, and monosaccate pollen Densipollenites spp. (D. invisus, D. densus, D. magnicorpus) corroborate with the latest Permian Raniganj (Lopingian) age. The rare occurrence of Densoisporites contactus and Lundbladispora warti in the assemblage, define the upper limit of the Raniganj Formation. The assemblages have been correlated with the Indian as well as other Gondwanian continents. The dominance of gymnosperms pollen glossopteridales, conifers, and cordaites, lesser quantitative spores of lycopsids, sphenopsids, filiciopsids algal elements indicate that the palaeoclimatic condition was warm and high humid, during the deposition of these sediments in the study area of the Raniganj Coalfield. Research Highlights: Palynological study has been carried out for the subsurface coal deposits from the borehole RB-1, drilled at Raniganj Coalfield to attempt to establish chronology of the sediments. The palynological investigation reveals three palynoassemblage zones and dated as early to latest Permian (Artinskian to Lopingian) age and this assemblage reveals the dominance of gymnosperms plant group such as Glossopteridales followed by conifers and cordaitales. The FADs (First appearance of Datum) of Densoisporites contactus, Lundbladispora warti and Lunatisporites pellucidus in the assemblage III indicate the end of Permian period. The overall palynological composition suggests that a warm to very hot with medium to low humidity climatic condition were prevailing in the study area. [ABSTRACT FROM AUTHOR]

The present work elucidates miofloral records from the Ganmachidam Formation (late Carboniferous–earliest Permian) of Spiti Valley, Tethyan Himalaya. The Ganmachidam Formation was hitherto considered as unfossiliferous, both for the faunal as well as floral records, and has been subjected to contentious age assessment. The present study has been carried out to find out the microfloral remains, assess the palynostratigraphic status, and the age of the Ganmachidam Formation. From the splintery shale sequence, a rich assemblage of palynomorphs has been recovered, having a dominance of monosaccate pollen grains, namely Parasaccites (Cannanoropollis), Crucisaccites, Divarisaccus, Densipollenites, Maculatasporites, followed by diverse bisaccate pollen grains, namely Scheuringipollenites, Crescentipollenites, Faunipollenites (Protohaploxypinus), Lunatisporites, Striatopodocarpites, Striatites, Rhizomaspora, Primuspollenites, and the spores Callumispora (Punctatisporites) and Calamospora in addition to woody fragments and fungal spores. Three palynoassemblages are identified. The recovered palynocomposition is corroborated with known records of palynomorphs from the Tethyan realm of India and from the late Carboniferous–Early Permian records of contemporaneous sequences across the globe. The composition of these palynoassemblages shows close correlation with the Crucisaccites monoletus Zone and Vittatina costabilis Interval Zone in the northeastern area of the Paraná Basin, Brazil, and lower Barakar palynozone (Scheuringipollenites barakarensis Assemblage Zone) of Peninsular India which indicates the studied section of the Ganmachidam Formation is late Pennsylvanian to early Permian in age. Moreover, occurrences of palynomorphs from the Carboniferous sequences having a glossopterid affinity further strengthen the idea that glossopterids might have originated in Carboniferous time. [ABSTRACT FROM AUTHOR]

The Gondwana sediments comprising fine-grained shales, carbonaceous shales, sandstones and the coal horizon in borecore RT-4 (approximately 547.00m thick) from Tamra block, Raniganj Coalfield, Damodar Basin, are analyzed palynologically. Based on the distribution pattern of marker palynotaxa, two assemblage zones are identified. In the Barren Measures Formation, dominance of enveloping monosaccate ( Densipollenites) along with striate bisaccate ( Striatopodocarpites, Faunipollenites) pollen taxa, and the FAD's of Kamthisaccites and Arcuatipollenites observed at 30.75, have equated this strata (30.75-227.80 m thick) with the Raniganj Formation of Late Permian in age. Downwards in the Barakar Formation, between 423.80-577.70 m depths, an abundance of non-striate ( Scheuringipollenites) and striate ( Faunipollenites and Striatopodocarpites) bisaccate pollen taxa is observed, that dates late Early Permian in age. Fair occurrences of hyaline, distorted and blackish-brown plant matter is observed within 231.00-408.40 m depths. Present study infers the existence of the Raniganj Formation in the lithologically delimited Barren Measures Formation in the study area, and the underlying unproductive strata (approx. 177.40m) might represent the part of the Barren Measures Formation. [ABSTRACT FROM AUTHOR]