Geology - Research Publications

Permanent URI for this collection

http://10.2.3.109/handle/32116/95

Browse

Now showing 1 - 20 of 29

The first report of cf. Zygolophodon (Mammalia, Proboscidea, Mammutidae) from the Upper Miocene of Kutch, India
(Taylor and Francis Ltd., 2023-04-25T00:00:00) Choudhary, Deepak; Jukar, Advait M.; Patnaik, Rajeev; Singh, Nongmaithem Amardas; Singh, Ningthoujam Premjit; Milankumar Sharma, K.
[No abstract available]
Lepidosauromorphs and associated vertebrate fauna from the Late Triassic Tiki Formation, South Rewa, Gondwana basin, India: implication for paleoenvironment and paleobiogeography
(Springer Nature, 2023-03-27T00:00:00) Singh, Y. Priyananda; Sharma, K. Milankumar; Tiwari, Raghavendra Prasad; Patnaik, Rajeev; Singh, Nongmaithem Amardas; Singh, Ningthoujam Premjit
Tiki Formation is well known for the presence of rich vertebrate fossil assemblages including archosaurians, cynodonts, xenacanthids, hybodonts and actinopterygians in the Gondwana succession of India. Here, we report indeterminate Sphenodontia and indeterminate Lepidosauromorpha from the Late Triassic Tiki Formation. The presently reported early diverging lepidosauromorphs might have fed on small invertebrates and small vertebrates/insects. The presence of early diverging lepidosauromorphs from the Tiki Formation extends their geographic range from Europe, N. America and S. America to the Indian sub-continent during the Late Triassic Period. Further, the reports of archosauromorph assemblages and the aquatic vertebrates from the Tiki Formation have strengthened the idea of affinities of vertebrate assemblages between Laurasia and Gondwana sub-continents of the Pangea. � 2023, Indian National Science Academy.
Climate Change Impact on Major River Basins in the Indian Himalayan Region: Risk Assessment and Sustainable Management
(Springer International Publishing, 2023-03-10T00:00:00) Amrutha, K.; Patnaik, Rasmi; Sandeep, A.S.; Pattanaik, Jitendra Kumar
Billions of people relay on water resources of the Himalayan region for drinking, irrigation, and other domestic purposes. Abundance of natural resources makes this region suitable for human settlements, despite the fact that the area experiences frequent natural hazards. Water resources including major rivers are one of the important components, responsible for high biodiversity of the Himalayas and its role in global atmospheric circulation. Recent climate changes have proved to affect the precipitation pattern and ice cover of the Himalayas, causing variations in the dynamics of rivers in the area. Climate change�induced variation in river flow quantity, timing, and unpredictability raises the danger of ecological changes and has a negative impact on aquatic life and the ecosystem depending on rivers. Agriculture is one important sector that is at highest risk due to climate change. This is a serious concern as the runoff patterns of the rivers are mainly determined by the precipitation pattern and ice cover in the upper reaches. Reduction in ice cover reduces the water storage capacity of the Himalayas, and fluctuations in the precipitation pattern cause floods and droughts. The increased frequency of natural hazards including floods and droughts affects the economy and is a threat to people�s life. Climate change effects on water resources, namely, Himalayan snow and ice reservoirs and lake and river systems and the risk associated with it, can be monitored using different hydrological models. To cover vast geographical areas of the Himalayan region, adequate hydrological observatories need to be installed in order to monitor and record time series data of the hydrological parameters. Systematic monitoring will help to predict how climate change will affect water resources in the future. Sustainable management of local resources based on suitable practices, adaptation strategies, and need-specific policies relevant to basin climate can further reduce frequent climate change-related impacts, risk, and vulnerability. � The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.
Clay minerals as paleo-climate proxy in Quaternary Dun sediments, NW Himalaya, India
(Springer Science and Business Media Deutschland GmbH, 2023-10-17T00:00:00) Amrutha, K.; Ahmad, Samad; Kumar, Pankaj; Pattanaik, Jitendra Kumar
Purpose: Clay mineral assemblages are widely used for deciphering paleoclimatic information, where diagenetic and detrital clays provide different signatures. The type and amount of clay present in the alluvial fan sediments account for the prevailing climate, topography, transport dynamics, diagenesis, and lithology of the catchment area. Clay mineral analysis of sediments collected from the younger lobe of Kiratpur Fan, Pinjaur dun, NW Himalaya, will help to understand the late-Quaternary climatic perturbations during marine isotope stage (MIS)-3 and to evaluate the suitability of clay minerals as paleoclimatic proxy. Materials and methods: Samples were collected from three sites along the Kiratpur Nadi near Paploha village, Haryana, where exposed sections had a total height of ~ 28�m. In this study, 31 samples from these sediment sections were collected and after initial processing, clay minerals were separated and oriented slides were prepared. These samples were analysed using X-ray diffractometer (XRD) with/without glycolation and heating treatments. One aliquot of dried clay from selected samples were used for FTIR to complement the XRD analysis. For FTIR analysis, about 1�mg of clay samples was mixed with ~ 10�mg of KBr and press pellets were prepared. Results and discussion: The clay fraction of these sediments constitute illite (~ 52 � 0.8%), kaolinite (~ 13 � 1.6%), and chlorite-montmorillonite interstratified clay (~ 35 � 1.5%). Shale and mudstone distributed in the catchment area might be the source of these clay minerals. Illite chemistry index of ~ 0.37 � 0.14, kaolinite/illite ratio (0.21�0.29), illite crystallinity (IC) (0.23 � 0.04), and kaolinite percentage suggest the dominance of physical weathering in the catchment area. These sediments are generated during a cold and dry period, and deposited during an aggradational phase associated with warm and wet phase within MIS-3 (40�30 Ka). Further, it was found that illite is the dominant clay throughout the Himalayas, Ganga plain, and Bay of Bengal (BoB) sediments, irrespective of their distance from the source. Hence, associating illite to younger and less-transported sediment does not work in this setting. Conclusion: Though the proxies based on clay percentage is very useful, only limited data is available. There is a significant difference in the value of IC in the Himalayan front and BoB sediments may be due to the modifications during the transportation of sediments. Overall, when sediments are transported for a longer distance, correlating clay mineral percentage with the maturity of sediment is not apparent. � 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Application of analytical hierarchy process and GIS techniques to delineate the groundwater potential zones in and around Jorhat and Majuli areas of eastern Assam, India
(Springer Science and Business Media Deutschland GmbH, 2022-10-26T00:00:00) Bordoloi, Abhiraj; Singh, Kshetrimayum Krishnakanta; Gaichunglu, Gangmei
Groundwater is regarded as prominently reliable natural resources available as fresh water. However, as the world advances at a tremendous rate, this hidden water resource is exposing continuous threats owing to numerous factors, such as improper uses, over-exploitation and quality contamination. The present study emphasizes on such challenges, especially on groundwater exploration in northeast region, India with the application of remote-sensing and GIS methods. Groundwater acts as a primary source of water supply for household and agricultural purposes in the study area. Parameters, such as rainfall, geomorphology, drainage density, lithology, LU/LC, soil, lineament density, slope and well yield data, were selected to prepare thematic maps. The thematic maps were created in remote sensing and GIS platforms and specific ranks and weights were assigned to each. A pair-wise examination of all the factors affecting the groundwater potential zone (GPZ) was used to derive the weights using an analytical hierarchy process and a multi-criteria decision-making approach to generate GPZ. Five potential zones have been classified as poor, fair, moderate, good and excellent. Based on the data obtained, the poor potential zone comprises 0.083% (2.11 km2), the fair groundwater zone consists of 7.21% (183 km2), the moderate zone contributes 27.4% (694.8 km2), the good zone shows 43.6% (1105.9 km2) and the excellent zone represents 21.7% (549.8 km2), respectively. Thus, such approach is proved to be effective, convenient and reliable as compared to other expensive and time-consuming techniques for groundwater mapping especially in a remotely located terrain. � 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
Chondrichthyan and osteichthyan fauna from the middle Miocene deposits of Palasava, Kutch, India: implication for paleoenvironment and paleobiogeography; [Faune de chondrichtyens et d�ost�ichtyens provenant des d�p�ts du Mioc�ne moyen de Palasava, Kutch, Inde: implication pour le pal�oenvironnement et la pal�obiog�ographie]
(Academie des sciences, 2022-12-13T00:00:00) Singh, Nongmaithem Amardas; Choudhary, Deepak; Singh, Y. Priyananda; Singh, Ningthoujam Premjit; Patnaik, Rajeev; Tiwari, R.P.; Sharma, K. Milankumar
The Neogene of Kutch, India is well known for its rich marine and terrestrial vertebrate assemblages. However, the data of piscean fauna from the middle Miocene of India is very scarce. We report here additional chondrichthyan and osteichthyan remains from the middle Miocene deposit of Chhasra Formation, Palasava site, Kutch, Gujarat, India. The elasmobranchs include Carcharhinus Blainville, 1816 (C. brevipinna (M�ller & Henle, 1839), C. falciformis (M�ller & Henle, 1839), C. cf. leucas, C. aff. perezi, Carcharhinus sp.), Negaprion Whitley, 1940 (Negaprion sp.), Aetobatus Blainville, 1816 (Aetobatus sp.), Myliobatis Cuvier, 1816 (Myliobatis sp.), Dasyatis Rafinesque, 1810 (D. probsti Cappetta, 1970, D. rugosa Probst, 1877), Himantura M�ller & Henle, 1837 (H. menoni Sahni & Mehrotra, 1981), Pastinachus R�ppell, 1829 (Pastinachus sp.), and Taeniurops Garman, 1913 (Taeniurops sp.). The teleosts of Palasava are represented by four families including Bagridae Bleeker, 1858, Channidae Fowler, 1934, Characidae Latreille, 1925 and Cyprinidae Cuvier, 1817. S�rensen-Dice coefficient data of Palasava elasmobranchs show a good similarity index with their counterparts in the Mediterranean Sea suggesting the existence of short-lived reopening of the marine pathway. However, a much higher faunal affinity with those of Eastern Pacific indicates a gradual shift in migration path through the Pacific Ocean to Indo-Pacific region after the permanent landbridge was formed. The vertebrate fauna from the Palasava suggests a coastal, marginal marine, near-shore littoral to neritic environment of deposition with the influence of freshwater riverine system. The integration of the floras and faunas from Palasava locality indicates the presence of warm, humid/ wet, tropical to sub-tropical environmental conditions during the middle Miocene. � 2022 Elsevier Masson SAS. All rights reserved.
First report on late Miocene (Tortonian: ~ 11�10�Ma) charophyte gyrogonites from Tapar, Kachchh District, Gujarat State, western India
(Springer Nature, 2022-09-05T00:00:00) Singh, Nongmaithem Amardas; Singh, Ningthoujam Premjit; Sharma, K. Milankumar; Patnaik, Rajeev; Tiwari, R.P.; Sehgal, Ramesh Kumar; Kumar, Vinay; Wazir, Wasim Abass; Singh, Y. Priyananda; Choudhary, Deepak
This paper describes the first record of charophyte gyrogonites from the late Miocene (Tortonian; ~ 11�10�Ma) Tapar locality of Kachchh, Gujarat State, western India. The recovered charophyte assemblage is constituted by Chara globularis var. aspera, C. globularis var. globularis, Lychnothamnus cf. sahnii, Lychnothamnus sp. and Nitellopsis sp. In addition, the present article discusses the palaeoenvironment based on the recorded charophyte gyrogonites (this study) and previously known faunal data (mainly vertebrates) from the Tapar locality, Kutch Basin, western India. Further, considering the significant extension of the biostratigraphic range [especially the First Appearance Datum (FAD)] of fauna from the Kutch Basin (in particular from the Tapar locality), we herein make an attempt to compare biostratigraphically the faunal assemblages from Kutch with those from the Siwalik Group, north India. � 2022, Indian National Science Academy.
Evolution of the Permo-Triassic Satpura Gondwana Basin, Madhya Pradesh, India: Insights from geochemical provenance and palaeoclimate of the siliciclastic sediments
(John Wiley and Sons Ltd, 2022-10-19T00:00:00) Singh, Yumlembam Priyananda; Kingson, Oinam; Sharma, Kongrailatpam Milankumar; Ghosh, Prosenjit; Patnaik, Rajeev; Tiwari, Raghavendra Prasad; Pattanaik, Jitendra Kumar; Kumar, Pankaj; Thomas, Harel; Singh, Ningthoujam Premjit; Singh, Nongmaithem Amardas
Geochemical study in the siliciclastic sediments of a basin provides an understanding of palaeoclimate, provenance and subsequently, it can be used to reconstruct the palaeo-tectonics and evolution of the basin. Sedimentation in the Gondwana basins, worldwide, generally provides a record of climatic fluctuations and evidences of the Permo-Triassic mass extinction. In spite of its global importance, our knowledge about the nature of sedimentation, basin development and conceptual regional tectonic model in the Satpura Basin, one of the Gondwana basins of India is limited. Major and trace element concentrations of the mudstones from the Denwa Formation along with the existing geochemical data of other formations are studied here for establishing a comprehensive idea about the palaeoclimate, tectonic settings, provenance and basin evolution. The composition of the sediments in the lowermost Talchir Formation revealed cold and dry climatic conditions at the sources, whereas the sources of the sediments for the overlying formations have experienced warm, humid and semiarid climates. The contributions of the mafic rock-derived sediments are relatively higher in the Talchir, Barakar and Motur formations compared to the overlying formations. Approximately 60% of the sediments in the overlying Bijori, Pachmarhi and Denwa formations were derived from the felsic volcanic rocks and granites of the Sausar Mobile Belt and Betul-Chindwara Mobile Belt (BCMB) with minor inputs from mafic volcanic rocks of the BCMB. Furthermore, the sediments of the Talchir Formation were derived from the BCMB when they became tectonically active, whereas the sediments in the younger formations have been derived from a passive tectonic setting. � 2022 John Wiley & Sons Ltd.
Open Science: Challenges, Possible Solutions and the Way Forward
(Springer Nature, 2022-09-02T00:00:00) Chakravorty, Nishant; Sharma, Chandra Shekhar; Molla, Kutubuddin A.; Pattanaik, Jitendra Kumar
Everyone agrees that scientific communication should be free for all. Unfortunately, accessing publications from many reputed journals comes at a high cost�a cost that many researchers and institutions cannot afford. Although,�open-access publication model�is considered by many as a possible route to ensure that�science�is free for all; however, it is fraught with its own challenges. This review attempts at exploring the possibilities of keeping�science�accessible. Firstly, we re-visit the meaning of �open�science� as a comprehensive concept which includes�open�source, data, access, resources, peer review etc. and not merely�open�access publication model. Next, we have discussed the global initiatives towards�open�access�the Budapest�Open�Access Initiative, Bethesda Statement on�Open�Access Publishing, Berlin Declaration on�Open�Access to Knowledge in the�Sciences�and Humanities, cOAlition S and its Plan S initiative, UNESCO Recommendation on Open Science and the San Francisco Declaration on Research Assessment (DORA). Following this we have included the�various open�access initiatives from India. In the next part, we have focused on problems with dissemination of�scientific�outcomes and the challenges associated with existing publication models. Finally, we explore the possible solutions to the existing challenges, which include promotion of pre-print servers and other ideas that we have detailed in the manuscript. � 2022, Indian National Science Academy.
Collective Affirmation in Action: Understanding the Success of Lockdown in India During the First Wave of the COVID-19 Pandemic
(Gonabad University of Medical Sciences, 2022-08-29T00:00:00) Tiwari, Gyanesh Kumar; Kashyap, Anil Kumar; Rai, Pramod Kumar; Tiwari, Raghavendra Prasad; Pandey, Ruchi
Background: This study explores the role of collective affirmation in attracting mass cooperation to motivate people to observe preventive measures during the COVID-19 pandemic. Methods: Using a qualitative research design, a heterogeneous sample (n=32) comprising postgraduate (n=10) and doctorates (n=22) was chosen and the data were collected through semi-structured interviews. The interview contents were audiotaped, transcribed verbatim, and analyzed via the thematic analysis method. Results: Five themes were generated in this study: perceived psychological distress, pandemic as a serious challenge to the national interest and human existence, the Janata curfew as a positive faith of the government in the abilities of Indians, lockdown as a strong faith of the government in the unshakable support of the Indians and strong affinity and pride of the Indians in their cultural heritage. The novelty, suddenness, and incurability of COVID-19 caused a set of perceived psychological distress and danger to individual and collective life. The Janata (public) curfew was perceived as a curfew of the people, by the people, and for the people. The lockdown denoted a strong faith of the Indian government in the positive virtues of the Indian people and vice versa. The mass support and adherence to the suggested preventive government measures were facilitated by collective affirmation of the well-known positive Indian cultural values (e.g. humanism, interdependence, collective pride, compassion, universal brotherhood, and so on) to the world. Conclusion: Collective affirmation inherent in the Indian cultural values catalyzed mass behavior change in the form of adherence to the essential restrictions and recommendations. Collective affirmation may have occurred because of the perceived faith of the government in the virtues of the Indians and their perceived administrative capability of the government. A culture-specific collective affirmation seems to emerge which initiated mass behavior changes leading to a successful lockdown. � 2022, Gonabad University of Medical Sciences. All rights reserved.
Geochronology and oxygen fugacity of the pelitic granulite from the Diwani hills, NE Gujarat (NW India)
(Cambridge University Press, 2022-08-01T00:00:00) Kumar, Manish; Prakash, D.; Singh, C.K.; Yadav, M.K.; Tewari, S.; Singh, Pradip K.; Mahanta, B.
The Diwani hills are located SE of Balaram-Abu Road in the Banaskantha district of north Gujarat. The crystalline rocks of the Diwani hill area are a diverse assemblage of Precambrian metamorphic and igneous rocks. These rocks are petrologically more complex and date back to the Aravallis or earlier. The mineralogical assemblages such as grt-sp-opx-qz of these rocks indicate their origin in anhydrous or dry conditions, implying metamorphism under pyroxene granulite facies. These granulitic rocks were subjected to Delhi orogenic deformation and were later intruded by the Erinpura granite. Textural and microstructural relationships, mineral chemistry, P-T-X pseudosection modelling and the oxidation state of pelitic granulites from the Diwani hill area of north Gujarat are all part of the current approach. The winTWQ program and pseudosection modelling in the NCKFMASHTO model system utilizing Perple_X software were used to restrict the P-T evolution of these pelitic granulites. The unification of these estimates shows that the pelitic granulites reached their pressure and temperature maxima at 8.6 kbar and 770 �C, respectively. The oxygen fugacity (log fO2) versus temperature computations at 6.2 kbar revealed log fO2-T values of -13.0 and 765 �C, respectively. The electron microprobe dating of monazite grains separated from the granulites of the Diwani hills yields ages ranging from 769 Ma to 855 Ma. The electron microprobe dating presented here from the Diwani hills provides evidence for a Neoproterozoic (Tonian) metamorphic event in the Aravalli-Delhi Mobile Belt. � The Author(s), 2022. Published by Cambridge University Press.
New rodents shed light on the age and ecology of late Miocene ape locality of Tapar (Gujarat, India)
(Taylor and Francis Ltd., 2022-08-05T00:00:00) Patnaik, Rajeev; Singh, Ningthoujam Premjit; Sharma, K. Milankumar; Singh, Nongmaithem Amardas; Choudhary, Deepak; Singh, Y. Priyananda; Kumar, Rohit; Wazir, Wasim Abass; Sahni, Ashok
The Miocene ape (Sivapithecus) locality of Tapar in Kutch (Gujarat, India) has yielded a diverse rodent assemblage that includes: a new murine Progonomys prasadi sp. nov., a new gerbilline Myocricetodon gujaratensis sp. nov., a new rhizomyne Kanisamys kutchensis sp. nov. and a new sciurine Tamias gilaharee sp. nov., beside additional remains of Progonomys morganae, Dakkamys asiaticus, Prokanisamys sp., Sayimys sivalensis and Democricetodon fejfari. Morphometric and PAUP based phylogenetic analyses place Progonomys prasadi sp. nov. within the Progonomys lineage. The cladogram obtained for the Siwalik murines suggest that Progonomys was ancestral to all the modern and one extinct murine genera recovered from the Siwaliks. The advanced features of Myocricetodon gujaratensis sp. nov. indicate that it was an immigrant to the subcontinent in the late Miocene. The cladistic analysis performed on Kanisamys kutchensis sp. nov. shows that it shared several advanced characters with contemporaneous Kanisamys nagrii and Kanisamys sivalensis. Based on the biostratigraphical ranges of Siwalik rodents and the co-occurrence of advanced forms of new and already reported murines, a new gerbilline and a new sciurine, we propose an age of ?10 Ma to the primate-bearing Tapar locality. Already reported stable isotope data on murines, and ecological preferences of modern counterparts of the fossil rodents and associated sharks and rays from Tapar locality, indicate that the Miocene ape Sivapithecus may have lived in a subtropical monsoonal forest close to the coast, very different from the present day arid conditions. http://zoobank.org/urn:lsid:zoobank.org:pub:12CE1B44-22A0-450F-9588-6C7F25242771. � The Trustees of the Natural History Museum, London 2022. All rights reserved.
Listriodon dukkar sp. nov. (Suidae, Artiodactyla, Mammalia) from the late Miocene of Pasuda (Gujarat, India): the decline and extinction of the Listriodontinae
(Springer Science and Business Media Deutschland GmbH, 2022-03-17T00:00:00) van der Made, Jan; Choudhary, Deepak; Singh, Ningthoujam Premjit; Sharma, K. Milankumar; Singh, Nongmaithem Amardas; Patnaik, Rajeev
The Listriodontinae were a common and widespread group of Suidae (pigs) that lived in an area extending from Portugal to China and to southern Africa. Here, we describe the new species Listriodon dukkar from Pasuda (Gujarat, India). It shares features with Li. pentapotamiae, evolved from it, and is the last representative of this lineage. The Listriodontinae flourished for about 10 million years, reached their maximum diversity and geographic extension during the Mid-Miocene Climatic Optimum (about 17�13.6�Ma), and their last records are close in age and date to�~ 9.8�Ma in the Indian Subcontinent, 9.78�Ma in Europe, and ~ 10�Ma in Africa. We review the environments in which the last listriodont lineages lived and went extinct. Their extinctions occurred against a background of increasing seasonality, vegetation change, a rise in bovid diversity and abundance, and local events, such as the European Vallesian Crisis and a dramatic drop in tragulid abundance in the Siwaliks. However, changes in the atmospheric pCO2 may have contributed to their decline and extinction in all their geographic distribution. Decreasing pCO2 is expected to have decreased sugar content and increased protein content of leaves and fruit. Hindgut fermenting Suoidea have higher protein requirements, while foregut fermenting Suoidea are more efficient in digesting sugars. Listriodontinae were probably foregut fermenters and were less well adapted in a low pCO2 world. � 2022, The Author(s).
Evaluation of seasonal dynamics of the surface water hydrochemistry using multivariate statistical techniques and aquatic macrophyte productivity in a mountainous lake, Northeast India
(Springer Science and Business Media Deutschland GmbH, 2022-05-13T00:00:00) Singh, Konthoujam Khelchandra; Singh, Kshetrimayum Krishnakanta; Usha, Khuraijam; Das, Subhasish; Singh, Salam Shantikumar
The present work elucidates the effective application of multivariate statistics in understanding the probable relations between surface water hydrochemistry and aquatic macrophyte productivity and their underlying seasonal dynamics in a remote mountainous lake of northeast India. The result of hierarchical cluster analysis revealed three distinct clusters corresponding to the pre-monsoon (35.42%), post-monsoon (52.08%), and monsoon (12.50%) seasons. The factor analysis yielded three principal components suggesting the sediment flux, farming discharge, domestic waste, bacterial oxidation of sulfur compounds, and dissolution of plant matters associated with dissolved feldspar minerals as the influential factors. The lake hydrochemistry also varied significantly, both spatially and temporally implying geogenic weathering processes from rock-soil-water interactions. Overall, sixteen aquatic macrophytes were identified, and their monthly and daily net primary productivity varied considerably in different seasons. Regression analysis highlighted the effect of temperature, total dissolved solids, electrical conductivity, and turbidity on the seasonal fluctuations in macrophyte productivity. Overall, the study provides insights into seasonal variation in the lake water chemistry and highlights the role of statistical tools in understanding the fragile aquatic ecosystems over cost-, labor-, and time-intensive inventory studies. � 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Biogeochemistry of the antarctic coasts: Implications for biodiversity and climate change
(Wiley Blackwell, 2022-04-01T00:00:00) Karayakath, Amrutha; Pattanaik, Jitendra K.; Saini, Khem C.; Kundu, Pushpendu; Bast, Felix
Notwithstanding its largely lifeless appearance, Antarctica hosts considerable biodiversity and ecosystem (trophic-level) complexity. Antarctic soils, ice-covered areas, coastal regions, and the surrounding Southern Ocean contributes to this biodiversity. However, studies related to the number of species present, how and where they are located and their influence on the ecosystem processes are still scarce. Biodiversity and biogeochemical cycles often coincide with climate change studies. Photosynthetic carbon fixation by phytoplanktons in the Antarctic coasts influences the atmospheric CO2 levels. On a geological timescale, such processes determine the climate. In this chapter, studies on Essential Ocean Variables and elemental cycles in Antarctica are reviewed to understand the biogeochemistry of the coast of Antarctica, and how these parameters and cycles influence the different coastal features of Antarctica. In the recent past, Antarctica has experienced a rapid rate of warming that in turn has threatened its biodiversity. The effects of climate change on biogeochemical parameters and their further consequences are therefore discussed here. The second half of this chapter deals with the prokaryotic as well as eukaryotic microbial diversities of Antarctica, and the implications they hold for climate change. � 2022 John Wiley & Sons, Inc. All rights reserved.
Career challenges for young independent researchers in India
(Indian Academy of Sciences, 2022-04-15T00:00:00) Agashe, Deepa; Maheshwary, Sugandha; Pattanaik, Jitendra Kumar; Prakash, Jai; Bhatt, Pragya; Arya, S.S.; Chatterjee, Sriparna; Kumar, Pankaj; Singh, Paramdeep; Abbas, Nazia; Sharma, Chandra Shekhar; Chaudhuri, Chirasree Roy; Devi, Pooja
The scientific enterprise in India has grown dramatically in the past few decades, with research emerging as a viable and important career option for students of science. The country thus has a large population of young scientists in the early stages of establishing their independent research careers. While this demographic is arguably the most important group that will determine the future of scientific research in India, their status and concerns are poorly understood. The Indian National Young Academy of Sciences conducted a national survey to better understand and present the challenges faced by them. Through a structured questionnaire, we sought the views of research-ers below 45 years of age. Here, we summarize the responses from 854 participants across multiple early career stages. We highlight key challenges faced by these scientists in establishing an inde-pendent research career, and suggest steps to address them. � 2022,Current Science.All Rights Reserved
A new window to the fossil herpetofauna of India: amphibians and snakes from the Miocene localities of Kutch (Gujarat)
(Springer Science and Business Media Deutschland GmbH, 2021-11-25T00:00:00) Singh, Ningthoujam Premjit; Patnaik, Rajeev; ?er?ansk�, Andrej; Sharma, K Milankumar; Singh, Nongmaithem Amardas; Choudhary, Deepak; Sehgal, Ramesh Kumar
The Miocene beds of Kutch in India are well known for their mammalian assemblages including an extinct ape Sivapithecus. We here report new amphibian and snake fossils, which have been recovered from two stratigraphic levels: the older Palasava locality which is dated to the middle Miocene (~ 14�Ma), whereas the sediments of younger sites at Tappar and Pasuda representing the late Miocene (~ 11�10�Ma). The amphibian material consists only of Rana sp., Ranidae indet. and Anura indet. The snake material is much more diverse and can be allocated to several taxa: Python sp., Acrochordus dehmi, Acrochordus sp., Ahaetuliinae indet. and Alethinophidia indet. Among all these finds, the fossils of Rana sp., Ahaetuliinae indet. and Python sp. described here form the first evidence of these taxa from the Neogene of India. The ectothermic faunas are good indicators of palaeoenvironmental conditions. The ectothermic vertebrate assemblages of these Indian localities indicate a very warm, humid/wet, tropical to sub-tropical environmental conditions during the middle and late Miocene. � 2021, Senckenberg Gesellschaft f�r Naturforschung and Springer-Verlag GmbH Germany, part of Springer Nature.
Distribution of neotectonic variability between the Kachchh Mainland Fault and Vigodi Fault, Northwestern Mainland Kachchh, Western India
(Elsevier Ltd, 2022-01-13T00:00:00) Kothyari, Girish Ch; Mishra, Sneha; Taloor, Ajay Kumar; Kandregula, Raj Sunil; Pathak, Vamdev; Chauhan, Gaurav
As per the Bureau of Indian Standards (BIS), the Kachchh region of the western peninsular India falls under seismically active region, where the faults experienced existence of several moderate to high magnitude earthquakes in the historic past. The present-day seismicity is mainly concentrated toward the eastern part of Kachchh Mainland Fault (KMF). Even though, the western segment of the KMF does not exhibit seismicity at present, but the tectono-geomorphology of this segment reveals various active geomorphic features which indicates its active nature. In this study, we are focusing on the distribution of neotectonic variability between the western segment of the KMF and the Vigodi Fault (VF), as the detailed geomorphometric studies is lacking in this region, believing that the area is not promising for such studies because the lack of seismicity. Therefore, we applied the conventional morphometric parameters to assess the neotectonic behaviour of the study area. The computed morphometric parameters had been grouped and mixed to create the Relative Index of Active Tectonics (RIAT), Furthermore, we used DInSAR results to estimate the active vertical displacement in between the fault zones which ranges from 0.15 to 0.28 cm. The results of each geomorphic indices indicates active deformation within the central portion of the western KMF and VF zone. This study would be certainly beneficial for seismic hazard assessment and future infrastructure planning of the region. � 2022 The Authors
A colubrid snake from the late Miocene of Kutch, Gujarat, India
(Palaeontological Society Of India, 2021-12-31T00:00:00) Singh, Ningthoujam Premjit; Singh, Nongmaithem Amardas; Kumar Sharma, K. Milan; Patnaik, Rajeev; Singh, Yumlembam Priyananda; Chaudhary, Deepak
Fossil snakes are extremely rare in the Indian Neogene records. We report the first record of isolated precloacal vertebrae of a �colubrine� snake from a late Miocene site, Tapar section in Kutch, Gujarat (India). The present specimens differ from the earlier finding of a colubrid from a younger deposit of Labli Member, Utterbaini Formation of Upper Siwaliks (Jammu and Kashmir) by the absence of hyapophyses. The �colubrine� snakes of late Miocene (~11-10 Ma) perhaps lived in a relatively wetter environment compared to the present �colubrine� from Kutch. � 2021 Palaeontological Society Of India. All rights reserved.
Luminescence chronology of Late Quaternary palaeo-lake deposits from the Upper Alaknanda Basin, Uttarakhand, India: Implication to palaeoclimate and depositional settings
(Elsevier Ltd, 2022-01-06T00:00:00) Pattanaik, Jitendra Kumar; Singh, Atul; Kumar, Haldhar; Singh Shah, Sunil; Semwal, Prabhat; Sujith Naik, M.; Nayak, Kalyani; Jaiswal, Manoj K.; Banerjee, Argha; Nainwal, Harish Chandra; Shankar, Ramachandran
Lakes downstream of the glaciers receive glacial meltwater and sediment supply resulting in formation of thick succession of lacustrine deposits. In this work, we have identified one such palaeo-lake deposit in the Upper Alaknanda Basin, close to Badrinath town. The sediments are of lacustrine origin; however the continuity is broken by intermittent fluvial deposits, which indicate changes in the depositional environment. We used Optically Stimulated Luminescence (OSL) dating to develop a robust chronology of the palaeo-lake deposit. Grain size analyses of sediments were carried out to understand the depositional environment, and morphometric analysis of the valley was conducted to obtained clues about the neotectonic activities in the region. The OSL ages show that the deposition of the lake sediments occurred between 21.6 � 4.7 ka to 10.5 � 1.4 ka. Two phases of paleo-lake deposit and subsequent outburst is established from the OSL age, grain size distribution and on the basis of field observations. The high sedimentation rate in the upper part of the deposit indicates an increase in the monsoonal rainfall and glacial retreat post Younger Dryas event. The colder periods are represented by varves and rhythmites, while the warmer periods are represented by thick laminated sand. This study indicates that the glaciers in the Upper Alakanada Basin responded to the fluctuations in the palaeo-climate. � 2022 Elsevier Ltd

Browse

Recent Submissions