@article {2963, title = {Indian monsoon variability during the past \~{}8.5~cal~kyr as recorded in the sediments of the northeastern Arabian Sea}, journal = {Quaternary International}, year = {2022}, month = {Jan-04-2022}, abstract = {We analyzed benthic and planktic foraminifera, total organic carbon and stable isotopes ratios of carbon and oxygen from 100 samples of marine sediment Core ABP, 25/03, off Gujarat in the northeastern Arabian Sea. Factor and cluster analyses of thirty highest-ranked benthic foraminifer species enabled to identify seven biofacies in the study sequence characterizing major changes in deep-sea environments during the past \~{}8.5 cal kyr. The benthic foraminiferal data has been combined with population abundances of upwelling indicator planktic foraminifer Globigerina bulloides and mixed layer species from Core ABP, 25/03 and compared with that from ODP Hole 723A and Core ABP, 25/02, western and eastern Arabian Sea, respectively. A major change in benthic foraminifera occurs during \~{}8.5 to 6 cal kyr BP, when the summer monsoon was stronger whereas during 6 to 2 cal kyr BP, the data suggest a weak summer monsoon. Planktic foraminifer Globigerina bulloides does not show any significant trend in the study core, but deep thermocline species Neogloboquadrina dutertrei and mixed layer species show significant trend with an inverse correlation with the TOC. This core records high TOC from \~{}6.5 to 4 cal kyr BP and during the last 2 cal kyr and low TOC during \~{}8.5 to 6.5 cal kyr BP and 4 to 2 cal kyr BP. It is interesting to note intervals of high mixed layer species coincide with high Neogloboquadrina dutertrei percentages and low TOC values at Core ABP, 25/03 during 8.5 to 6.5 cal kyr BP.The faunal data is supported by carbon and oxygen isotope ratios (δ13C and δ18O) of shells of benthic foraminifer Cibicides spp. to strengthen our understanding of changes in the eastern Arabian Sea since \~{}8.5 cal kyr BP.}, issn = {10406182}, doi = {10.1016/j.quaint.2022.03.016}, url = {https://linkinghub.elsevier.com/retrieve/pii/S104061822200115X}, author = {Ravichandran, M. and Gupta, Anil K. and Mohan, K. and Tiwari, Sameer K. and Lakshumanan, C. and Panigrahi, M.K.} } @article {208, title = {East{\textendash}West similarities and differences in the surface and deep northern Arabian Sea records during the past 21 Kyr}, journal = {Palaeogeography, Palaeoclimatology, Palaeoecology}, volume = {301}, year = {2011}, note = {id: 2100}, pages = {75-85}, abstract = {This study analyses monsoon proxy Globigerina bulloides from Ocean Drilling Program (ODP) Hole 723A (western Arabian Sea) and Hole ABP-25, 02 (northeastern Arabian Sea) as well as dominant benthic foraminifera, pteropods, total organic carbon (TOC), Inorganic Carbon (IC) and stable isotope values of benthic foraminifera from Hole ABP-25, 02 to understand summer monsoon-driven changes in the western and eastern Arabian Sea and their impacts on deep-sea ventilation during the past 21 Kyr. We have also combined published TOC data from ODP Hole 724B to understand if deep-sea conditions in the Arabian Sea were same throughout the region during the studied interval. The summer monsoon was generally weaker during cold intervals including the Last Glacial Maximum, the Younger Dryas and the Bond events of the Holocene. From 20 to 10 Kyr, the deep northeastern Arabian Sea was better oxygenated with less organic carbon supply except during 14{\textendash}12.5 Kyr when TOC values increased, indicating a weaker summer monsoon and a weak oxygen minimum zone (OMZ). The TOC values and the abundance of the eutrophic benthic foraminiferal species Bulimina aculeata, Melonis barleeanum and Uvigerina peregrina increased during the late Holocene whereas well-oxygenated, low organic carbon benthic species Sphaeroidina bulloides as well as pteropods decreased, indicating an intense OMZ and an increased supply of refractory organic material to the Arabian Sea. It is important to note that although the surface response to monsoon variability was more or less similar in the western and northeastern Arabian Sea, the deep-sea conditions show a marked contrast in the two regions during the past 21 Kyr.}, issn = {0031-0182}, doi = {10.1016/j.palaeo.2010.12.027}, url = {http://www.sciencedirect.com/science/article/pii/S0031018211000022}, author = {Gupta, Anil K. and Mohan, K. and Sarkar, Sudipta and Clemens, Steven C. and Ravindra, Rasik and Uttam, Rajesh K.} }