The paper reports palynology and palynofacies studies of lignite-bearing sediments exposed in an opencast mine succession at Surkha, Bhavnagar District, in the coastal region of Gujarat, India. The study examined the relationships between the palynoflora, sedimentary organic matter and environment at the time of deposition of lignite and associated sediments. Based on dinoflagellate cyst biostratigraphy, the sedimentary succession is dated as early Eocene (Ypresian). Palynofacies studies helped reveal the palaeoenvironmental fluctuations. The dominance of angiosperm pollen grains, freshwater algae, microthyraceous fungi and a large share of land debris in the lower part of the succession suggests a freshwater swamp environment of deposition for the basal lignite facies. Two cenozones - Matanomadiasulcites maximus and Lakiapollis ovatus - were identified in the lower lignite facies, determined from the dominance of these pollen grains in the palynological assemblages. The presence of angiosperm pollen grains and pteridophyte spores in the carbonaceous shale horizon above the lignite facies indicates a change in the depositional regime from freshwater swamp to lagoonal. This was identified as the Arecipites wodehousei cenozone due to its numerical abundance in the assemblage. Dinoflagellate cyst abundance and diversity, and microforaminiferal test linings along with well-sorted terrestrial debris in the mudstone in the upper part of the succession suggest a more open marine estuarine type of depositional environment. The Homotryblium complex along with Cordospheridium fibrospinosum, Kenleyia sp., and Thalassiphora pelagica dinoflagellate cysts are the main representatives of this zone, determined as the Homotryblium tenuispinosum cenozone. The changing depositional settings (freshwater swamp-lagoonal-estuarine) along the vertical succession indicate a marine transgression in this region. Results from palynological studies of early Palaeogene successions of the Cambay and Kutch basins correlate well with the present findings.

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A 105 m early Eocene section exposed in the Gurha Mine in the Nagaur-Ganganagar Basin, Rajasthan, India, archiving remains of equatorial vegetation at a time of extreme global warmth and close to the onset of the India-Eurasia collision, is investigated using palynostratigraphic and palynofacies analyses. Four palynozones e.g., Palmidites plicatus Singh, Botryococcus braunii Kützing, Triangulorites bellus Kar and Ovoidites ligneoulus are identified stratigraphically on the basis of abundance of these pollen taxa over others. The occurrence of taxonomically highly diverse angiosperm pollen in all the four palynozones attest to an extremely rich near-coastal tropical flora subject to frequent wildfires under a strongly seasonal precipitation regime. Palynotaxa characteristic of these palynozones are widely distributed in other early Paleogene sediments of India. Sedimentary organic matter (structured terrestrial, biodegraded, amorphous, grey amorphous, resins, charcoal/black- A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT2 brown debris and algal remains) recovered from mire and lacustrine sediments are of terrestrial origin, recording fluctuations in burial anoxia and salinity. Episodes of elevated salinity are due either to seepage of marine waters and/or a periodic excess of evaporation over precipitation at times when the depositional system was closed.

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The coal and carbonaceous shales collected from the Tura Formation (late Palaeocene) of Nangwalbibra, East Garo Hills, Meghalaya, have been analysed for palynological study to deduce palaeovegetation and palaeoclimate. The palynoflora represented by pteridophytic spores and angiospermic pollen grains shows similarity with other contemporaneous deposits of the Garo, Khasi and Jaintia Hills of Meghalaya. The palynoassemblage dominated by angiosperms depicts subtropical to tropical vegetation during the late Palaeocene in the region. The fossil pollen grains show their similarity with modern plants of various tropical angiosperm families, like Alangiaceae, Anacardiaceae, Annonaceae, Arecaceae, Bombacaceae, Clusiaceae and Gunneraceae, etc. which indicate the existence of tropical evergreen to moist deciduous forest. Some of the taxa resemble the floral elements growing near swamps in the tropical zone. The fossil palynoflora indicates warm and humid climate during the depositional period. The study is supported by plant megafossil data known from the same horizon.