Amit K. Ghosh

Birbal Sahni Institute of Palaeosciences · Marine Micropaleontology

The deposition of a substantial amount of clastic sediments in the Krishna Godavari Basin formed a thick layer of nannofossil-rich clay known as the Godavari Clay Formation. This clayey sequence is a treasure trove for unveiling paleoclimatic and paleoceanographic information. Numerous radiometric dates from the topmost portion of this clay (top 27...

Amongst the various Neogene sequences in India, Andaman-Nicobar Basin in the northern Indian Ocean is one of the most important basins in this part of the world that represents the marine deep-water facies with a few shallow-water sequences. The Neogene sediments of the basin archives abundant siliceous microfossils namely radiolarians, diatoms, si...

Non-geniculate rhodolith-forming coral red algae have been recorded in the Long Formation, exposed in four different outcrops on Little Andaman Island (Hut Bay). Non-geniculate corallines are represented by species of Sporolithon Heydrich, 1897, Mesophyllum Lemoine, 1928, Lithothamnion Heydrich, 1897, Phymatolithon Foslie, 1898, Lithoporella (Fosli...

Analysis of the Tortonian sediments in the northeast Indian Ocean from NGHP–01–17A drilled at Andaman Basin shows 22 silicoflagellate taxa belonging to the genera Bachmannocena, Dictyocha, Distephanopsis, Paramesocena and Stephanocha. This study records the first evidence of Tortonian silicoflagellates from the offshore of northeast Indian Ocean. T...

The approximate age of Planet Earth is around 4.54 billion years. This age of the earth has been determined from isotopic dating of the rock samples from the earth’s crust as well as from the soils and rocks of the moon and meteorites. Dating methods e.g., Rubidium (87R) – Strontium (87Sr) and Uranium (238U, 235U, 232U) – Lead (206Pb, 207Pb, 208Pb)...

A detailed study on radiolarian biostratigraphy and paleoecology has been carried out from three outcrops on Havelock Island, belonging to the Ritchie's Archipelago of Andaman and Nicobar Group of islands. Though most of the radiolarian taxa are moderately preserved, it was possible to demarcate an age ranging from late early to early middle Miocen...

The oldest Asian record of alpheid shrimps (assigned to genus Alpheus) based on snapping claw fingertips from the Miocene (Aquitanian) Khari Nadi Formation (Kutch Basin, western India) reported herein extends the fossil record of Alpheidae from Asia by ~22 million years. An early Miocene (Aquitanian) age is estimated, based on the associated assemb...

Relatively large specimens (6–12 μm long) of the nannolith Nicklithus amplificus are characteristic of the late Miocene, having evolved in NN11 from the typical Miocene species Orthorhabdus rugosus. The present study was performed in order to identify the earliest occurrence, and to examine the evolutionary lineage, palaeogeography and palaeoclimat...

In this paleological study we focused on a coralline red algae-rich shoal grainstone facies in the Lower Miocene (Aquitanian) carbonates of the Qom Formation in the Vartun sectionin central Iran. The identified coralline red algae are mainly non-geniculate, although very rare geniculate forms of corallines were also recognized in thin section analy...

The present study has been carried out from the NGHP sediment core (NGHP-01-17A) of northeast Indian Ocean on different siliceous microfossils represented by diatoms and radiolarians along with calcareous nannofossils. Samples from the bottommost subunit Ic of the sediment core (684.09 mbsf to 369.62 mbsf) have been analysed. This contribution is t...

Pramanik S., Keshri J.P., Kar R. & Ghosh A.K. 2021. Megaspores of heterosporous lycopsid affinity from the late Permian of Chhattisgarh, Central India and their evolutionary significance. Journal Botanical Society of Bengal. 75 (2): 1-16.

Primary productivity is an important component of the ocean. Primary productivity data from Pliocene of northern Indian Ocean is lacking. Marine siliceous organisms viz., diatoms, radiolarians, silicoflagellates and siliceous sponges uptake dissolved silica (dSi) from the seawater. The biological uptake of dissolved silica (dSi) from the seawater a...

Understanding the recovery of life and its radiation after the Permian–Triassic mass extinction event (PTME) that took place around 252.28 ± 0.08 Ma is a fascinating aspect of Earth science studies. In this backdrop, we have undertaken a study of the floral diversity based on plant macrofossils and megaspores from the late Permian and early Triassi...

Thirty-two planktonic foraminiferal taxa have been identified based on Bright Field microscopic study as well as Scanning Electron Microscopy on the samples collected from the outcrop adjacent to the type section of Neill West Coast Formation at Neil Island of Ritchie's Archipelago, northern Indian Ocean. The planktonic foraminiferal taxa belong to...

Neogene sediments of the Andaman and Nicobar Islands in northern Indian Ocean, specifically the lower Miocene (Burdigalian) to lower Pliocene (Zanclean) sequences, were analysed for calcareous nannofossils that yielded well-preserved and diverse assemblages. The majority of samples contained stratigraphic marker taxa that allowed us to identify suc...

The present contribution provides a study of calcareous nannofossils and siliceous microfossils from the Sawai Bay Formation on Car Nicobar Island, northern Indian Ocean. Two stratigraphically short sediment intervals near Sawai Bay have been examined. Qualitative and quantitative microfossil analyses show the Sawai Bay ‘A’ Section to be devoid of...

In the Ritchie’s Archipelago of the Andaman group of islands (Northern Indian Ocean), Havelock Island is the largest one. The present study on diatoms has been carried out on three outcrops of Havelock Island situated in Kalapathar, South Point and Laccam Point localities. Samples collected from the three Neogene outcrops yielded poor to moderately...

In the present study from the late Pliocene of Neill West Coast Formation, Neil Island, serpulid tubes assignable to Ditrupa gracillima Grube have been identified with the help of tube morphological (light microscopy) and ultrastructural (SEM) studies. This is the first record of the species from the late Pliocene of India. The outer layer of D. gr...

Microfossil assemblages and lithological variations of the marine Cretaceous-Palaeocene (Danian) self succession of the Cauvery Basin, southern India has been a matter of attraction for the geoscientists and palaeontologists since the mid-nineteenth century. As a matter of fact, it has provided world class data on the invertebrates from the mid Cre...

Meeting Report: 12th International Symposium on Fossil Algae, Lucknow, India - September 16-18, 2019

The present study on coralline red algae has been carried out from the limestone unit belonging to the Kakana Formation of Car Nicobar Island. An assemblage dominated by coralline red algae (both non-geniculate and geniculate) represents the coralline algal flora of Car Nicobar Island. Altogether 7 species of non-geniculate corallines and 7 differe...

Field Guide book to Andaman and Nicobar Islands

Abstract volume of 12th International Symposium on Fossil Algae

Kar R., Saha S., Haque F., Pramanik S. & Ghosh A. K. 2018. Occurrence of Barakar (Early Permian) coal from Barapukuria Basin, Bangladesh. Geophytology 48(2): 125-129.

In the Havelock Island of the Ritchie’s Archipelago (northeastern Indian Ocean), two lithological successions viz., the Inglis and Long formations, are exposed. Chronostratigraphically, the Havelockian Regional Stage has been named on this island for the sediments of both the formations. Based on previous planktonic foraminiferal biostratigraphy, t...

Kar, R. & Ghosh, A.K., May 2018. First record of Reduviasporonites from the Permian–Triassic transition (Gondwana Supergroup) of India. Alcheringa XX, XXX–XXX. ISSN 0311-5518. We have performed a palynological study from an outcrop succession within the Gondwana Supergroup in India, spanning the end-Permian event. The sampled succession is located...

The occurrence of a diverse range of conifers and bennettitales is characteristic of the macroflora from the Early Cretaceous of the Rajmahal Basin, India. In the present paper two new conifer taxa assigned to the families Cupressaceae and Podocarpaceae are described from the intertrappean sediments of the Rajmahal Formation in Jharkhand State. The...

Taxonomic analysis of fresh water phytoplankton based on bright field microscopy and SEM studies is yet to be done in depth that may elucidate a number of new taxa. The present study on the assemblage of fresh water phytoplankton is focused to interpret the ecological condition of the studied water body of Bankura District in West Bengal. Phytoplan...

The present paper deals with the occurrence of a Halimeda bioherm facies represented by five different forms of the genus. The halimedaceans have been identified by thin section analysis of limestones from the middle Miocene (Serravallian) of the Butler Bay Section, Little Andaman Island (Hut Bay), India. All these forms are reported herein for the...

Petrographic thin section analysis of the samples collected from the type section of Neil West Coast Formation, situated in the west coast of Neil Island yielded moderately preserved coralline red algae, benthic and planktic foraminifers, coral fragments, echinoid spines and gastropod shells. The coralline red algae are represented by both non-geni...

The late Miocene (Tortonian) diatoms in 21 outcrop samples from Neil Island, Andaman and Nicobar Islands were investigated with eighty two planktonic and benthic taxa belonging to 35 genera. Principal Component Analysis reveals the existence of two distinct groups; samples dominated by Thalassionema nitzschioides and Thalassiothrix longissima, belo...

The macroflora of the Parsora Formation is unique in terms of its diversity and comprises a diverse array plant groups. Variety of plant macrofossils having affinities with pteridophytes, pteridosperms and gymnosperms have been reported and described earlier from the Parsora Formation since the last phase of 19th century. However, affinities and id...

Diatoms were collected from the Kotulpur area of West Bengal. Four diatom taxa, namely, Eunotia minor (Kützing) Grunow, Achnanthidium minutissimum (Kützing) Czarnecki, Lemnicola hungarica (Grunow) Round and Basson, and Navicula radiosa Kützing were observed using scanning electron microscopy (SEM) and identified in light of modern diatom taxonomic...

Biofacies analysis is used to understand the palaeoenvironmental implications of late middle Miocene (Serravallian) algal-foraminiferal assemblages and carbonate deposition pertaining to the Hut Bay section of the Little Andaman Island, India. This study is based on the novel dataset of coralline algae and benthic foraminifera evaluated from the th...

Neogene radiolaria from late Miocene sediments of Andaman and Nicobar Islands

Lithological variations and fossil assemblages of the marine Cretaceous–Palaeocene (Danian) self succession of the Cauvery Basin, southern India has been a matter of attraction for the geoscientists and palaeontologists since the mid-nineteenth century. As a matter of fact, it has provided world class data on the invertebrates from the mid Cretaceo...

Ghosh, A.K., Kar, R.K. & Chatterjee, R., 2015. Leaf galls on Dicroidium hughesii (Feistmantel) Lele from the Triassic of India—a new record. Alcheringa 39, xxx–xxx. ISSN 0311-5518.Disc-like galls are reported on the Triassic corystosperm leaf Dicroidium hughesii (Feistmantel) Lele from the Parsora Formation of South Rewa Gondwana Basin, central Ind...

Tidal variations of phytoplankton were studied at two stations i.e., Station - 1 (Science Centre) and Station - 2 (Junglighat Bay) during the period of December 2010 to February 2011 in the coastal waters of South Andaman Islands, India. Phytoplankton biomass (Chlorophyll-a) was observed low (avg. 0.02- 0.1 mg m-3) in the stations during the sampli...

The genus Dicroidium Gothan, belonging to Corystospermaceae, is characterised by pinnately compound leaves with proximally forked primary rachis. The genus was earlier included under the genus Thinnfeldia Ettingshausen. Dicroidium is the most consistent macrofloral element in the Triassic strata of Southern Hemisphere. The present reassessment deal...

Till date the Lakadong, Umlatdoh and Prang Formations of Meghalaya have accounted for detailed taxonomic and palaeoecological investigations of numerous coralline red algal taxa. However, record of coralline red algae hitherto unknown from the overlying Kopili Formation (late Eocene). This is the first explicit record of corallinacean red algae fro...

The 'Lilliput effect' represents the phenomenon whereby there is a pronounced reduction in the size of biota associated with the aftermath of mass extinction. This fact has been supported by the evidence of dwarfism both in invertebrates and vertebrates recorded after the end-Permian mass extinction event. The extinct genus Glossopteris belonging t...

Plant remains, including both mega and micro collected from the middle part of the Tharumsa Foramtion (early Miocene) are described for the first time from the Tharumsa village of the Kargil district, Jammu and Kashmir to reconstruct the palaeoenvironment. They indicate their affinities with Broussonetia of the Moraceae and Abies, Cedrus and Pinus...

The present study deals with the diversity of phytoplankton from two selected stations, (Station 1: Junglighat and Station 2: Science Centre) during December 2010 to February 2011 in the coastal waters of Port Blair, South Andaman. Special emphasis was given to visualise the phytoplankton assemblages of the selected stations during low tide and hig...

Palaeodiversity of coralline algae has been studied from the Serravallian carbonate sediments out-cropping in the Little Andaman Island (Hut Bay). Little Andaman is the southernmost island of the Andaman Group, situated between South Andaman and Car Nicobar. The algae described in the present case study have been recovered from the fossiliferous li...

Palaeocene-Eocene carbonates of shallow marine sequence belonging to Shella Formation of Jaintia Group are well developed in the south of the Jaintia Hills, Meghalaya and represent an excellent outcrop of shelf sediments in North Eastern Himalaya, India. These outcrops are exposed along the southern fringe of Shillong Plateau. The Prang Limestone i...

Ghosh, A.K. and Sarkar, S. 2014. EUTROPHICATION : A FORMIDABLE FOE. Everyman's Science, Vol XLVIII No. 5, Dec 13-Jan 14.

Miocene diatoms from the Havelock Island of Ritchie’s Archipelago Group, South Andaman with interpretation on Palaeoenvironment Arindam Chakraborty, Abhijit Mazumder & Amit K. Ghosh Birbal Sahni Institute of Palaeobotany, 53 University Road Lucknow-226 007, Uttar Pradesh, INDIA E-mail: flywidari@gmail.com, abhijit.mazumder.email@gmail.com, akghos...

Ghosh Amit K. 2013. Search for extreme climatic events of the past earth deep below the seafloor. Petals, 1(2): 10-18

Facies characterization of Piacenzian (late Pliocene) carbonate sediments of the Guitar Formation in Car Nicobar Island, India and the subsequent integration of paleoecological data have been applied to interpret the paleoenvironment of the coralline algal-reef deposits. Thin-section analysis reveals that Amphiroa, Corallina and Jania are the domin...

TIDAL VARIATION OF PHYTOPLANKTONS IN SOUTH ANDAMAN AND ITS IMPLICATIONS ON THE FUTURE CLIMATE CHANGE Arindam Chakraborty1,2, Gadi Padmavati2, Amit K Ghosh1 Email: flywidari@gmail.com 1. Birbal Sahni Institute of Palaeobotany, Lucknow-226007, Uttar Pradesh, India. 2. Department of Ocean studies and Marine Biology, Pondicherry University, Brooksha...

Ghosh Amit K. & Sarkar S. 2013. Fossil calcareous algae from the Hydrocarbon-Potential Sedimentary Basins of India. In: (Verma, P.K. Editor) Selected Topics in Earth System Sciences, Volume II, pp. 92-98.

The family Sporolithaceae has recently been separated from Corallinaceae owing to the distinct anatomical characteristics of calcified sori, apical plugs and cruciately arranged spores. By virtue of systematic studies on living as well as fossil specimens at the global level, Sporolithon has been accepted as the generic name for all the species ear...

The southwestern part of south Shillong plateau (Meghalaya, N-E India), designated as Sylhet Limestone Group is sub-divided into three lithounits i.e., Lakadong, Umlatdoh and Prang formations in ascending order. The Prang Formation is the youngest lithostratigraphic unit of the Sylhet Limestone Group and has been dated as Middle to early Upper Eoce...

Coral bleaching has emerged as an outright menace for the coral reefs right through their global distribution range. Despite being rated among the highly diverse biological ecosystems on the earth, coral reefs are deteriorating at an alarming rate due to severe intensification of multiple natural and human-induced disturbances, especially in the tr...

The Kargil Molasse Group of northwest Ladakh Himalaya is divided into Kargil, Tharumsa and Pashkyum formations, composed mainly of sandstone, mudstone, siliceous clay and grey to dark brown carbonaceous shale. Plant fossils recorded in these sequences are represented by angiosperm leaf impressions, pteridophytic spores, gymnosperm and angiosperm po...

Integrated Ocean Drilling Program Expedition 342 was designed to recover Paleogene sedimentary sequences with unusually high deposition rates across a wide range of water depths (Sites U1403-U1411). The drilling area is positioned to capture sedimentary and geochemical records of ocean chemistry and overturning circulation beneath the flow of the D...

Macroscopic fossil charcoal has been discovered in the carbonaceous shales associated with Seam-VI of Raniganj Formation, Upper Permian, Damodar Basin, India. A pycnoxylic gymnosperm wood is described and confirms the occurrence of palaeo-wildfire in this area during the Late Permian. The integration of the data presented in the current study with...

Mazumder A., Govil P., Ghosh Amit K. & Ravindra R. 2012. Significant Research on Diatom in Antarctic Lake during Last Decade. Journal of Algal Biomass Utilization. 3(4): 74-79. Study of diatom became one of the very promising fields in present science all over the world. Both biologists and geologists use this unicellular microorganism for differen...

The carbonate rocks of the Shella Formation (Middle Eocene) belonging to the Jaintia Group in the Jaintia Hills of Meghalaya are represented by two sandstone units in alternation with three limestone units, viz. Lakadong Limestone, Umlatdoh Limestone and Prang Limestone respectively in chronological order. Umlatdoh Limestone, the middle limestone u...

The present paper deals with the plant megafossil assemblage from the Maitur Formation, the lower part of Panchet Group of rocks, unconformably overlain by coal bearing Raniganj Formation in Raniganj Coalfield, West Bengal. The plant fossils are collected from two localities exposed in Nonia Nala Section near Asansol, Burdwan District, West Bengal....

Pa/aeobotanisr 59/20}0) .' }07-JJ9 003/-0/74/20/0 $100 (Received 0 I July, 20 I0; revised version accepted 26 August, 20 I0) ABSTRACf Ghosh AK & Sarkar S 20 IO. Contemporary taxonomic perspectives of fossil Coralline Red Algae: their possible origin and evolution. The Palaeobotanist 59(1-3) : 107-119. Studies done by various phycologists have broug...

Mehrotra R.C., Kumar M. & Ghosh Amit K. 2009. An expedition to Kargil, Jammu & Kashmir. BSIP News Letter No. 12: 17-18.

Ghosh Amit K & Singh B.D. 2008. Report on the XXI Indian Colloquium on Micropalaeontology and Stratigraphy. BSIP News Letter No. 11: 18-19.

The Shell Limestone (Nilkanth Formation) of the Mussoorie Synclme, Lesser Himalaya, Uttaranchal, India has yielded varied biota i e bryozoa, echinoid radiole, hydrozoa, foraminifers, green algae and several casts of bivalve genera Presence of Cenocava mlkanthi Smgh, 1980, a bryozoan recorded earlier fiom the Coralhne Limestone of the Bagh Beds (Cre...

Thin section analysis of Umlatodh Limestone belonging to Shella Formation exposed in the southern part of Jaintia Hills yielded well preserved calcareous algae. Detailed taxonomical analyses of the algal forms reveal the existence ofudoteacean and halimedacean green algae that includes three species of the genus Ovulites Lamarck belonging to family...

Ghosh Amit K. & Banerji J. 2007. Biostratigraphic significance of megaspores from the Triassic sequence of Peninsular India. Micropaleontology: Application in Stratigraphy and Paleoceanography. (Editor: D.K. Sinha) Publisher: Narosa Publishing House Pvt. Ltd., New Delhi.pp. 81-89.