Journal articles on the topic 'Indian Ocean marine sediment'
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Lawler, Kelly-Anne, Giuseppe Cortese, Matthieu Civel-Mazens, Helen Bostock, Xavier Crosta, Amy Leventer, Vikki Lowe, John Rogers, and Leanne K. Armand. "The Southern Ocean Radiolarian (SO-RAD) dataset: a new compilation of modern radiolarian census data." Earth System Science Data 13, no. 11 (November 25, 2021): 5441–53. http://dx.doi.org/10.5194/essd-13-5441-2021.
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Abstract. Radiolarians (holoplanktonic protozoa) preserved in marine sediments are commonly used as palaeoclimate proxies for reconstructing past Southern Ocean environments. Generating reconstructions of past climate based on microfossil abundances, such as radiolarians, requires a spatially and environmentally comprehensive reference dataset of modern census counts. The Southern Ocean Radiolarian (SO-RAD) dataset includes census counts for 238 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian, and southwest Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. As well as describing the data collection and collation, we include recommendations and guidelines for cleaning and subsetting the data for users unfamiliar with the procedures typically used by the radiolarian community. The SO-RAD dataset is available to download from https://doi.org/10.1594/PANGAEA.929903 (Lawler et al., 2021).
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Jiang, Zhao, Wei-Hua Zhang, Chang-Guo Yuan, Jia-Yang Chen, Li-Xiang Cao, Dong-Jin Park, Min Xiao, Chang-Jin Kim, and Wen-Jun Li. "Kocuria subflava sp. nov., isolated from marine sediment from the Indian Ocean." Antonie van Leeuwenhoek 108, no. 6 (September 11, 2015): 1349–55. http://dx.doi.org/10.1007/s10482-015-0587-z.
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Phillips, Stephen C., and Kate Littler. "Comparison of sediment composition by smear slides to quantitative shipboard data: a case study on the utility of smear slide percent estimates, IODP Expedition 353, northern Indian Ocean." Scientific Drilling 30 (February 25, 2022): 59–74. http://dx.doi.org/10.5194/sd-30-59-2022.
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Abstract. Smear slide petrography has been a standard technique during scientific ocean drilling expeditions to characterize sediment composition and classify sediment types, but presentation of these percent estimates to track downcore trends in sediment composition has become less frequent over the past 2 decades. We compare semi-quantitative smear slide composition estimates to physical property (natural gamma radiation, NGR) and solid-phase geochemical (calcium carbonate, CaCO3 %) measurements from a range of marine depositional environments in the northern Indian Ocean (Bay of Bengal, Andaman Sea, Ninetyeast Ridge) collected during International Ocean Discovery Program (IODP) Expedition 353. We show that presenting smear slide estimates as percentages, rather than abundance categories, reveals similar downcore variation in composition to the more quantitative core analyses. Overall downcore trends in total calcareous components from smear slides (foraminifers + nannofossils + shell fragments + authigenic carbonate) follow similar downcore trends to samples measured by CaCO3 coulometry. Total lithogenic components (clay + mica + quartz + feldspars + lithic grains + vitric grains + glauconite + heavy minerals + iron oxides) and clay from smear slides track reasonably well with NGR measurements. Comparison of site averages of absolute percentages of total calcium carbonate from coulometry and total calcareous components from smear slide observations reveals an overestimation in carbonate percentages in smear slides (likely due in part to underestimation of the clay fraction), especially in sediments rich in smectite clays. Differences in sediment color between sites and settling of clay particles during slide preparation may contribute to this discrepancy. Although smear slide estimates range in accuracy depending on the training of the operator, we suggest that sedimentologists describing cores obtained during scientific drilling can use the percent estimates of sedimentary components in smear slides to identify trends and cyclicity in marine sediment records.
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Yin, Q. Z., and Z. T. Guo. "Strong summer monsoon during the cool MIS-13." Climate of the Past 4, no. 1 (February 28, 2008): 29–34. http://dx.doi.org/10.5194/cp-4-29-2008.
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Abstract. The δ18O record in deep-sea sediments show a significant reduced amplitude of the ice volume variations before Marine Isotope Stage 11, about 400 ka ago, with less warm interglacials and less cold glacials. The deuterium temperature and the greenhouse gases records in the Antarctic ice cores show the same feature. As the reduction in the amplitude of climate and greenhouse gases concentration variations before 400 ka BP is present in both deep-sea and ice cores, it is tempting to conclude that this is a worldwide phenomenon. This is not necessarily true, at least as far as some of the records, in particular of China and Europe, are concerned. The loess in northern China, the sedimentary core in the eastern Tibetan Plateau and the palaeosols in southern China all record an unusually warm and wet climate during Marine Isotope Stage 13, indicating an extremely strong East Asian summer monsoon. The pollen record from Europe shows that the climatic conditions during the interglacials previous to Marine Isotope Stage 11 are at least as warm as the younger interglacials. During Marine Isotope Stage 13, unusually strong African and Indian monsoon are recorded in the sediments of the equatorial Indian Ocean and of the Mediterranean Sea. Other extreme climate events are also recorded in sediment cores of the equatorial Atlantic, the Pacific, the subtropical South Atlantic Ocean and in the Lake Baikal of Siberia.
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Chen, Rou-Wen, Ke-Xin Wang, Fa-Zuo Wang, Yuan-Qiu He, Li-Juan Long, and Xin-Peng Tian. "Rubrobacter indicoceani sp. nov., a new marine actinobacterium isolated from Indian Ocean sediment." International Journal of Systematic and Evolutionary Microbiology 68, no. 11 (November 1, 2018): 3487–93. http://dx.doi.org/10.1099/ijsem.0.003018.
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Buck, Lucy, Charlie Bristow, and Ella Meilianda. "After the Indian Ocean Tsunami (IOT): Natural beach recovery, Meulaboh, Sumatra, Indonesia." E3S Web of Conferences 340 (2022): 01002. http://dx.doi.org/10.1051/e3sconf/202234001002.
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Ground-penetrating radar (GPR) offers an efficient and non-invasive method of identifying and characterising subsurface features. It has previously been used to investigate both tsunami deposits and marine erosion surfaces from tsunamis as well as the structure of the structure of prograding beaches. The present study investigates beach deposits at Meulaboh, western coast of Aceh Province in Sumatra Island of Indonesia, to estimate the volume of sediment that has been deposited since the 2004 Indian Ocean Tsunami, using the GPR with an antenna of 200 MHz. Two profiles perpendicular to the coastline were collected, one 93 m long and the other 30 m long, to capture the internal profile of beach ridge deposition. From the GPR measurement the amount of 1,190,191,716 tons of sediment redeposited along the 1092 m coastline since the 2004 tsunami, with a prograding length of 73 m per year. As beaches provide a good form of tsunami protection the rapid beach recovery and the return of a large amount of sediment helps provide much needed coastal protection to the area.
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Yin, Q. Z., and Z. T. Guo. "Strong summer monsoon during the cool MIS-13." Climate of the Past Discussions 3, no. 5 (October 11, 2007): 1119–32. http://dx.doi.org/10.5194/cpd-3-1119-2007.
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Abstract. The δ18O record in deep-sea sediments show a significant reduced amplitude of the ice volume variations before Marine Isotope Stage 11, about 400 kyr ago, with less warm interglacials and less cold glacials. The deuterium temperature and the greenhouse gases records in the Antarctic ice cores show the same feature. As the reduction in the amplitude of climate and greenhouse gases concentration variations before 400 kyr BP is present in both deep-sea and ice cores, it is tempting to conclude that this is a worldwide phenomenon. This is not necessarily true, at least as far as some of the records, in particular of China, are concerned. The loess in northern China, the sedimentary core in the eastern Tibetan Plateau and the palaeosols in southern China all record an unusually warm and wet climate during Marine Isotope Stage 13, indicating an extremely strong East Asian summer monsoon. During the same interglacial, unusually strong African and Indian monsoon are recorded in the sediments of the equatorial Indian Ocean and of the Mediterranean Sea. Other extreme climate events are also recorded in sediment cores of the equatorial Atlantic, the Pacific, the subtropical South Atlantic Ocean and in the Lake Baikal of Siberia.
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Dunlea, Ann G., Liviu Giosan, and Yongsong Huang. "Pliocene expansion of C<sub>4</sub> vegetation in the Core Monsoon Zone on the Indian Peninsula." Climate of the Past 16, no. 6 (December 23, 2020): 2533–46. http://dx.doi.org/10.5194/cp-16-2533-2020.
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Abstract. The expansion of C4 vegetation during the Neogene was one of the largest reorganizations of Earth's terrestrial biome. Once thought to be globally synchronous in the late Miocene, site-specific studies have revealed differences in the timing of the expansion and suggest that local conditions play a substantial role. Here, we examine the expansion of C4 vegetation on the Indian Peninsula since the late Miocene by constructing a ∼6-million-year paleorecord with marine sediment from the Bay of Bengal at Site U1445, drilled during International Ocean Discovery Program Expedition 353. Analyses of element concentrations indicate that the marine sediment originates from the Mahanadi River in the Core Monsoon Zone (CMZ) of the Indian Peninsula. Hydrogen isotopes of the fatty acids of leaf waxes reveal an overall decrease in the CMZ precipitation since the late Miocene. Carbon isotopes of the leaf wax fatty acids suggest C4 vegetation on the Indian Peninsula existed before the end of the Miocene but expanded to even higher abundances during the mid-Pliocene to mid-Pleistocene (∼3.5 to 1.5 million years ago). Similar to the CMZ on the Indian Peninsula, a Pliocene expansion or re-expansion has previously been observed in northwest Australia and in East Africa, suggesting that these tropical ecosystems surrounding the Indian Ocean remained highly sensitive to changes in hydroclimate after the initial spread of C4 plants in late Miocene.
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Putra, Purna Sulastya, and Septriono Hari Nugroho. "Distribusi Sedimen Permukaan Dasar Laut Perairan Sumba, Nusa Tenggara Timur." Oseanologi dan Limnologi di Indonesia 2, no. 3 (December 28, 2017): 49. http://dx.doi.org/10.14203/oldi.2017.v2i3.118.
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<strong>Subsurface sediment distribution in the Sumba Waters, East Nusa Tenggara.</strong> Marine geological survey of the Ekspedisi Widya Nusantara 2016 was conducted in the Sumba Waters on 4 to 26 August 2016 using Baruna Jaya VIII research vessel. The aim of this survey was to reveal the type and characteristics of the subsurface sediments of the Sumba Waters. A total of 13 samples were taken from the different depth in the subsurface bottom of the sea using grabbing methode with box corer. Grain size analysis were conducted using Mastersizer 2000 to understand the characteristics and the sediment type distribution. In general, the type of the subsurface sediment in the Sumba Waters is ranging from medium to very coarse sandy silt. Distribution of the subsurface sediments is correlated to depths. Grain size of the sediments in the Sumba Strait is coarser than in the western and southern of Sumba Island that directly connected to the Indian Ocean. Distribution of the subsurface sediment showing that the sediment, which are distributed further away from the coast is poorly sorted. The deposition of the subsurface-sea sediment is interpreted to represent a calm, and slow sedimentation mechanism under uniform suspension process.
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Amsler, Helen Eri, Lena Mareike Thöle, Ingrid Stimac, Walter Geibert, Minoru Ikehara, Gerhard Kuhn, Oliver Esper, and Samuel Laurent Jaccard. "Bottom water oxygenation changes in the southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception." Climate of the Past 18, no. 8 (August 9, 2022): 1797–813. http://dx.doi.org/10.5194/cp-18-1797-2022.
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Abstract. We present downcore records of redox-sensitive authigenic uranium (U) and manganese (Mn) concentrations based on five marine sediment cores spanning a meridional transect encompassing the Subantarctic and Antarctic zones in the southwestern Indian Ocean covering the last glacial cycle. These records signal lower bottom water oxygenation during glacial climate intervals and generally higher oxygenation during warm periods, consistent with climate-related changes in deep-ocean remineralized carbon storage. Regional changes in the export of siliceous phytoplankton to the deep sea may have entailed a secondary influence on oxygen levels at the water–sediment interface, especially in the Subantarctic Zone. The rapid reoxygenation during the deglaciation is in line with increased ventilation and enhanced upwelling after the Last Glacial Maximum (LGM), which in combination conspired to transfer previously sequestered remineralized carbon to the surface ocean and the atmosphere, contributing to propel the Earth's climate out of the last ice age. These records highlight the still insufficiently documented role that the Southern Indian Ocean played in the air–sea partitioning of CO2 on glacial–interglacial timescales.
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Lemenkova, Polina. "Sediment thickness in the Bay of Bengal and Andaman Sea compared with topography and geophysical settings by GMT." Ovidius University Annals of Constanta - Series Civil Engineering 22, no. 1 (December 1, 2020): 13–21. http://dx.doi.org/10.2478/ouacsce-2020-0002.
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Abstract The study presents an analysis of the sediment thickness compared with bathymetric and geophysical settings in the Bay of Bengal and Andaman Sea, Indian Ocean. It uses a combination of the high-resolution data: topographic GEBCO, satellite and marine gravity anomalies, EGM2008 geoid and GlobSed to visualize the correlation between relief, gravity and trends in continent-ocean sediment transport. The results include thematic maps and 3D model showing increased sediment thickness in the Bengal Fan (8,0 to 8,2 km) in NE direction with maximum in Ganges Fan (16,2 km), and southward decrease in the Andaman Sea from Irrawaddy river mouth (6-7 km) to the Strait of Malacca (1-2 km). All maps and 3D model have been plotted by Generic Mapping Tools (GMT) cartographic scripting toolset version 6.0.0.
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Schulz, Hartmut, Kay-Christian Emeis, Helmut Erlenkeuser, Ulrich von Rad, and Christian Rolf. "The Toba Volcanic Event and Interstadial/Stadial Climates at the Marine Isotopic Stage 5 to 4 Transition in the Northern Indian Ocean." Quaternary Research 57, no. 1 (January 2002): 22–31. http://dx.doi.org/10.1006/qres.2001.2291.
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AbstractThe Toba volcanic event, one of the largest eruptions during the Quaternary, is documented in marine sediment cores from the northeastern Arabian Sea. On the crest of the Murray Ridge and along the western Indian continental margin, we detected distinct concentration spikes and ash layers of rhyolithic volcanic shards near the marine isotope stage 5–4 boundary with the chemical composition of the “Youngest Toba Tuff.” Time series of the Uk′37-alkenone index, planktic foraminiferal species, magnetic susceptibility, and sediment accumulation rates from this interval show that the Toba event occurred between two warm periods lasting a few millennia. Using Toba as an instantaneous stratigraphic marker for correlation between the marine- and ice-core chronostratigraphies, these two Arabian Sea climatic events correspond to Greenland interstadials 20 and 19, respectively. Our data sets thus depict substantial interstadial/stadial fluctuations in sea-surface temperature and surface-water productivity. We show that variable terrigenous (eolian) sediment supply played a crucial role in transferring and preserving the productivity signal in the sediment record. Within the provided stratigraphic resolution of several decades to centennials, none of these proxies shows a particular impact of the Toba eruption. However, our results are additional support that Toba, despite its exceptional magnitude, had only a minor impact on the evolution of low-latitude monsoonal climate on centennial to millennial time scales.
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Mampuku, M., T. Yamanaka, M. Uchida, R. Fujii, T. Maki, and H. Sakai. "Changes in C<sub>3</sub>/C<sub>4</sub> vegetation in the continental interior of the Central Himalayas associated with monsoonal paleoclimatic changes during the last 600 kyr." Climate of the Past 4, no. 1 (January 2, 2008): 1–9. http://dx.doi.org/10.5194/cp-4-1-2008.
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Abstract. A continuous lacustrine sediment core obtained from the Kathmandu Valley in the Central Himalayas revealed that cyclical changes in C3/C4 vegetation corresponded to global glacial-interglacial cycles from marine isotope stages (MIS) 15 to MIS 4. The C3/C4 vegetation shifts were reconstructed from significant changes in the δ13C values of bulk organic carbon. Glacial ages were characterized by significant 13C enrichment, due to the expansion of C4 plants, attributed to an intensification of aridity. Thus, the southwest (SW) summer monsoon, which brings the majority of rainfall to the Central Himalayan southern slopes, would have been weaker. Marine sediment cores from the Indian Ocean and Arabian Sea have demonstrated a weaker SW monsoon during glacial periods, and our results confirm that arid conditions and a weak SW monsoon prevailed in the continental interior of the Central Himalayas during glacial ages. This study provides the first continuous record for the continental interior of paleoenvironmental changes directly influenced by the Indian monsoon.
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Mampuku, M., T. Yamanaka, M. Uchida, R. Fujii, T. Maki, and H. Sakai. "Changes in C<sub>3</sub>/C<sub>4</sub> vegetation in the continental interior of the Central Himalayas associated with monsoonal paleoclimatic changes during the last 600 kyr." Climate of the Past Discussions 3, no. 4 (July 6, 2007): 871–98. http://dx.doi.org/10.5194/cpd-3-871-2007.
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Abstract. A continuous lacustrine sediment core obtained from the Kathmandu Valley in the Central Himalayas revealed that cyclical changes in C3/C4 vegetation corresponded to global glacial-interglacial cycles from marine isotope stages (MIS) 15 to MIS 4. The C3/C4 vegetation shifts were reconstructed from significant changes in the δ13C values of bulk organic carbon. Glacial ages were characterized by significant 13C enrichment, due to the expansion of C4 plants, attributed to an intensification of aridity. Thus, the southwest (SW) summer monsoon, which brings the majority of rainfall to the Central Himalayan southern slopes, would have been weaker. Marine sediment cores from the Indian Ocean and Arabian Sea have demonstrated a weaker SW monsoon during glacial periods, and our results confirm that arid conditions and a weak SW monsoon prevailed in the continental interior of the Central Himalayas during glacial ages. This study provides the first continuous record for the continental interior of paleoenvironmental changes directly influenced by the Indian monsoon.
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Bunzel, Dorothea, Gerhard Schmiedl, Sebastian Lindhorst, Andreas Mackensen, Jesús Reolid, Sarah Romahn, and Christian Betzler. "A multi-proxy analysis of Late Quaternary ocean and climate variability for the Maldives, Inner Sea." Climate of the Past 13, no. 12 (December 13, 2017): 1791–813. http://dx.doi.org/10.5194/cp-13-1791-2017.
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Abstract. As a natural sediment trap, the marine sediments of the sheltered central part of the Maldives Inner Sea represent an exceptional archive for paleoenvironmental and climate changes in the equatorial Indian Ocean. To evaluate the complex interplay between high-latitude and monsoonal climate variability, related dust fluxes, and regional oceanographic responses, we focused on Fe ∕ Al, Ti ∕ Al and Si ∕ Ca ratios as proxies for terrigenous sediment delivery and total organic carbon (TOC) and Br XRF counts as proxies for marine productivity. Benthic foraminiferal fauna distributions, grain size and stable δ18O and δ13C data were used for evaluating changes in the benthic ecosystem and changes in the intermediate water circulation, bottom water current velocity and oxygenation. Our multi-proxy data record reveals an enhanced dust supply during the glacial intervals, causing elevated Fe ∕ Al and Si ∕ Ca ratios, an overall coarsening of the sediment and an increasing amount of agglutinated benthic foraminifera. The enhanced dust fluxes can be attributed to higher dust availability in the Asian desert and loess areas and its transport by intensified winter monsoon winds during glacial conditions. These combined effects of wind-induced mixing of surface waters and dust fertilization during the cold phases resulted in an increased surface water productivity and related organic carbon fluxes. Thus, the development of highly diverse benthic foraminiferal faunas with certain detritus and suspension feeders was fostered. The difference in the δ13C signal between epifaunal and deep infaunal benthic foraminifera reveals intermediate water oxygen concentrations between approximately 40 and 100 µmol kg−1 during this time. The precessional fluctuation pattern of oxygen changes resembles that from the deep Arabian Sea, suggesting an expansion of the oxygen minimum zone (OMZ) from the Arabian Sea into the tropical Indian Ocean with a probable regional signal of strengthened winter-monsoon-induced organic matter fluxes and oxygen consumption further controlled by the varying inflow intensity of the Antarctic Intermediate Water (AAIW). In addition, the bottom water oxygenation pattern of the Maldives Inner Sea reveals a long phase of reduced ventilation during the last glacial period. This process is likely linked to the combined effects of generally enhanced oxygen consumption rates during high-productivity phases, reduced AAIW production and the restriction of upper bathyal environments in the Inner Sea during sea-level lowstands. Thus, our multi-proxy record reflects a close linkage between the Indian monsoon oscillation, intermediate water circulation, productivity and sea-level changes on orbital timescale.
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Lemenkova, Polina. "Insights on the Indian Ocean Tectonics and Geophysics Supported by GMT." Risks and Catastrophes Journal 27, no. 2 (December 5, 2020): 67–83. http://dx.doi.org/10.24193/rcj2020_12.
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This paper presented analyzed and summarized data on geological and geophysical settings about the tectonics and geological structure of the seafloor of the Indian Ocean by thematic visualization of the topographic, geophysical and geological data. The seafloor topography of the Indian Ocean is very complex which includes underwater hills, isolated mountains, underwater canyons, abyssal and accumulative plains, trenches. Complex geological settings explain seismic activity, repetitive earthquakes, and tsunami. Understanding and prognosis of the disastrous and catastrophic geological events is strongly based on correct data analysis, modelling and visualization. An important feature of this paper is mapping multi-source high-resolution data by GMT. Data include raster grids in NetCDF and GRD formats: ETOPO1, geologic and marine free-air gravity data, EGM96, age, spreading rates, and spreading asymmetry of the ocean crust by NOAA, total sediment thickness. Data were visualized by GMT modules to compare and analyze geophysical and geological settings of the Indian Ocean. Visualization reveled correlations between high bathymetric variations of the oceanic seafloor, distribution of main geological seafloor fabric: Southwest, Southeast, Mid and Carlsberg ridges. Tectonic maps were plotted to perform comparative analysis of several variables: crust age, spreading half rates (mm/yr), asymmetries in crustal accretion on conjugate ridge flanks (%), variations in the geopotential and gravimetric models. Being the warmest of the world’s ocean, Indian Ocean has specific climatic conditions (repetitive monsoons, tsunamis, cyclones and storms), complex geologic seafloor structure with triple junction and unique geographic settings. Presented paper contribut ed to the regional studies of the Indian Ocean.
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SEN, AREEN, RATUL SAHA, KUPPUSWAMY SIVAKUMAR, and PUNYASLOKE BHADURY. "Inventorizing the modern benthic foraminiferal assemblage from marginal marine environments across the North West coast of Bay of Bengal." Zootaxa 4441, no. 2 (June 27, 2018): 245. http://dx.doi.org/10.11646/zootaxa.4441.2.3.
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Modern benthic foraminiferal assemblages are instrumental in providing information regarding changes in relative sea level as well as prevailing environmental conditions in marine environments. Marginal marine environments are coastal environments that are in most cases characterized by high influx of terrestrially originated nutrients. Inventorizing of modern benthic foraminiferal assemblages from such habitats can act as biotic indicators of water quality variations along with any changes in relative sea level. The present study documents the modern benthic foraminiferal assemblage from three major marginal marine habitats located along the North West coast of Bay of Bengal, in the Indian Ocean. Sediment samples for the purpose were thus collected from the Indian Sundarbans Delta, Chilika lagoon and the Gautami Godavari estuarine zone which encompasses the Kakinada bay. A total of 32 species of benthic foraminifera were documented during the study. The present observations were compared with previous reports of benthic foraminiferal diversity from these habitats and exhibited variability.
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Walsh, Emily A., John B. Kirkpatrick, Robert Pockalny, Justine Sauvage, Arthur J. Spivack, Richard W. Murray, Mitchell L. Sogin, and Steven D'Hondt. "Relationship of Bacterial Richness to Organic Degradation Rate and Sediment Age in Subseafloor Sediment." Applied and Environmental Microbiology 82, no. 16 (June 10, 2016): 4994–99. http://dx.doi.org/10.1128/aem.00809-16.
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ABSTRACTSubseafloor sediment hosts a large, taxonomically rich, and metabolically diverse microbial ecosystem. However, the factors that control microbial diversity in subseafloor sediment have rarely been explored. Here, we show that bacterial richness varies with organic degradation rate and sediment age. At three open-ocean sites (in the Bering Sea and equatorial Pacific) and one continental margin site (Indian Ocean), richness decreases exponentially with increasing sediment depth. The rate of decrease in richness with increasing depth varies from site to site. The vertical succession of predominant terminal electron acceptors correlates with abundance-weighted community composition but does not drive the vertical decrease in richness. Vertical patterns of richness at the open-ocean sites closely match organic degradation rates; both properties are highest near the seafloor and decline together as sediment depth increases. This relationship suggests that (i) total catabolic activity and/or electron donor diversity exerts a primary influence on bacterial richness in marine sediment and (ii) many bacterial taxa that are poorly adapted for subseafloor sedimentary conditions are degraded in the geologically young sediment, where respiration rates are high. Richness consistently takes a few hundred thousand years to decline from near-seafloor values to much lower values in deep anoxic subseafloor sediment, regardless of sedimentation rate, predominant terminal electron acceptor, or oceanographic context.IMPORTANCESubseafloor sediment provides a wonderful opportunity to investigate the drivers of microbial diversity in communities that may have been isolated for millions of years. Our paper shows the impact ofin situconditions on bacterial community structure in subseafloor sediment. Specifically, it shows that bacterial richness in subseafloor sediment declines exponentially with sediment age, and in parallel with organic-fueled oxidation rate. This result suggests that subseafloor diversity ultimately depends on electron donor diversity and/or total community respiration. This work studied how and why biological richness changes over time in the extraordinary ecosystem of subseafloor sediment.
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Kavazos, Christopher R. J., Megan J. Huggett, Ute Mueller, and Pierre Horwitz. "Biogenic processes or terrigenous inputs? Permanent water bodies of the Northern Ponds in the Lake MacLeod basin of Western Australia." Marine and Freshwater Research 68, no. 7 (2017): 1366. http://dx.doi.org/10.1071/mf16233.
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The saline wetlands of the Northern Ponds, Lake MacLeod, contravene general classifications for salt lakes because, despite enduring high levels of evaporation, they contain permanently inundated ponds that are continually supplied with seawater by a seepage face from the Indian Ocean. The present study investigated the physical, sediment and chemical characteristics of these ponds, using sonar, flow-rate measurements, microscopy and inductively coupled plasma–mass spectrometry to understand the role of biogenic and terrigenous inputs on the benthic habitats. The chemical composition of the water bodies did not differ significantly from the seawater feedstock, which facilitates biogenic sediment accumulation. The largest permanent water body differs from the other ponds in physical and chemical structure, in that, possibly because of its size, it is dominated by terrigenous inputs, which result in higher nutrient concentrations and non-biogenic sediments. The Northern Ponds represent a system where the hydrology permits the establishment of permanent wetlands in an arid environment. Because of the constant supply of seawater, the ponds have a blend of habitat characteristics from marine and other inland salt-lake environments. The present study showed that a ‘marine-like’ state can override more typical characteristics of inland water bodies where discharge rates are high and water-residence times are low.
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Mackie, Andrew S. Y., P. Graham Oliver, Teresa Darbyshire, and Kate Mortimer. "Shallow marine benthic invertebrates of the Seychelles Plateau: high diversity in a tropical oligotrophic environment." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 363, no. 1826 (January 15, 2005): 203–28. http://dx.doi.org/10.1098/rsta.2004.1488.
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Soft sedimentary biotopes are extensive in the shallow Western Indian Ocean, especially on the Seychelles Plateau and Mascarene Ridge, yet pro rata compared with coral reefs the research effort devoted to them has been minimal. In this study we examine the benthic mollusc and polychaete worm assemblages of the shallow waters (11–62 m) around Mahé, in the Seychelles, and make direct comparisons with the temperate Irish Sea area and subtropical waters of Hong Kong, China (using identical methodology). Two assemblages were recognized, characterized by depth and sediment type. Of these, assemblage A (in shallow carbonate sands) was the most diverse, with diversity and richness measures exceeding those from the Irish Sea or Hong Kong. Hong Kong generally had the poorest fauna. Considering the Bivalvia alone, estimates of taxonomic distinctness showed this to be least for Seychelles assemblage A. The degree of conformity of the results to the concept of the latitudinal gradient in species richness and the possible underlying causes are discussed. Comparisons with other data suggest that the Seychelles support a benthic fauna at least as diverse as any other described from the tropics. A tentative examination of total bivalve species richness suggests a total of 400–500 for the Seychelles. This is in keeping with other Indian Ocean localities, but higher than known figures for continental east Africa. The findings of this paper support the case for widespread ecological and taxonomic studies of the Western Indian Ocean benthic invertebrates.
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Mironov, O. G. "Brief chronicle of A. O. Kovalevsky IBSS Department of Marine Sanitary Hydrobiology oceanic studies." Marine Biological Journal 4, no. 2 (June 24, 2019): 96–100. http://dx.doi.org/10.21072/mbj.2019.04.2.10.
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A brief overview of the work in the Atlantic, Indian and Pacific oceans in the period 1967–1988 is given. Data on the distribution patterns and abundance of microorganisms capable of using oil hydrocarbons as the single source of carbon and energy are given. The accumulation of oil hydrocarbons by marine organisms, the effect of thin suspension of deep-water (5000 m) bottom sediments and ferromanganese nodules on zooplankton, and the toxicity of artificial polymers for marine biota are discussed. The expediency of the resumption of similar work in the World Ocean in modern environmental conditions is expressed.
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Gradstein, Felix M., Zehui Huang, Inger L. Kristiansen, and James G. Ogg. "Optimum microfossil sequences and cyclic sediment patterns in Early Cretaceous pelagic strata." Canadian Journal of Earth Sciences 30, no. 2 (February 1, 1993): 391–411. http://dx.doi.org/10.1139/e93-029.
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Three sequencing methods were used to calculate the most likely biozonation and the periodicity of sedimentary cycles in Lower Cretaceous pelagic strata of the Atlantic and Indian oceans.A database was built of 378 first and last stratigraphic occurrences of calcareous nannofossils, dinocysts, foraminifers, and geomagnetic reversals in highest Jurassic through Lower Cretaceous deep marine strata at 10 Atlantic Ocean and 3 Indian Ocean drilling sites. There are 135 different events in total, about one third of which are unique to either ocean. Using the complete data set, the quantitative stratigraphy methods STRATCOR and RASC calculated closely comparable optimum sequences of average first- and last-occurrence positions. The preferred zonal solution, based on the STRATCOR method, includes 56 events, each of which occurs at three or more sites. The events comprise 6 geomagnetic reversals, 25 nannofossils, 5 planktonic foraminifera, 8 benthic foraminifera, and 12 dinocysts occurrences. Nine assemblage zones have been recognized of Tithonian through Albian age. All but 2 of 18 nannofossil events in the Atlantic Ocean optimum sequence were reported in the same stratigraphic order in a standard Mesozoic nannofossil zonation.Our quantitative examination, using Walsh spectral analysis, of the Lower Cretaceous cyclic sequences at three Deep Sea Drilling Project (DSDP) sites in the Atlantic Ocean generally supports the hypothesis that they are the product of cyclic climatic changes controlled by the Milankovitch orbital cycles. The peaks in the power spectra usually can be related to obliquity and precession cycles; some peaks seem to correspond to the eccentricity cycle. Obliquity seems to be the most important and persistent orbital element responsible for cyclic sedimentation in the Early Cretaceous Atlantic Ocean.The actual pelagic sedimentation rates were calculated for some cores using the results of spectral analysis. The correlation of the actual pelagic sedimentation rate with cyclic patterns and the occurrence of calcareous turbidites indicate that the changes in cycle pattern are the reflection of changes in the oceanographic setting. The changes in oceanographic setting are related to relative-sea-level fluctuations. The intervals dominated by laminated limestone were deposited during higher sea-level periods.
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Courtillat, Margot, Maximilian Hallenberger, Maria-Angela Bassetti, Dominique Aubert, Catherine Jeandel, Lars Reuning, Chelsea Korpanty, Pierre Moissette, Stéphanie Mounic, and Mariem Saavedra-Pellitero. "New Record of Dust Input and Provenance During Glacial Periods in Western Australia Shelf (IODP Expedition 356, Site U1461) from the Middle to Late Pleistocene." Atmosphere 11, no. 11 (November 20, 2020): 1251. http://dx.doi.org/10.3390/atmos11111251.
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International Ocean Discovery Program (IODP) Expedition 356 Site U1461 represents one of the few records from the North West Australian shelf that provides information about aridity fluctuations in Australia during the Quaternary. A combination of chronostratigraphic indicators revealed the (partial) preservation of two major glaciations (Marine Isotope Stage (MIS) 2 and MIS 12) in the sedimentary record. The faunal content (mainly benthic foraminifera, corals and bryozoans) was analyzed to estimate paleo-environments and paleo-depths in order to determine if these sediments have been remobilized by reworking processes. Despite the occurrence of a depositional hiatus (including MIS 5d to MIS 9-time interval), the excellent preservation of faunal content suggests that the preserved sediment is in situ. The geochemical composition of the sediments (Nd and major elements) indicates that during MIS 12 riverine input was likely reduced because of enhanced aridity, and the sediment provenance (mainly atmospheric dust) is likely in the central (Lake Eyre) or eastern (Murray Darling Basin) parts of the Australian continent. MIS 2 is confirmed to be one of the driest periods recorded in Australia but with mixed dust sources from the eastern and western parts of the continent. More humid conditions followed the glacial maximum, which might correspond to the peak of the Indian-Australian Summer Monsoon.
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Lemenkova, Polina, and O. Debeir. "Satellite Altimetry and Gravimetry Data for Mapping Marine Geodetic and Geophysical Setting of the Seychelles and the Somali Sea, Indian Ocean." Journal of Applied Engineering Sciences 12, no. 2 (December 1, 2022): 191–202. http://dx.doi.org/10.2478/jaes-2022-0026.
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Abstract Evaluation of the representative cartographic techniques demonstrated that there are still considerable challenges facing the methods of marine geodetic, geophysical and bathymetric data visualisation. In an oceanic seafloor formation, the interaction between the geological structural elements and topographical relief can be analysed by advanced mapping. In present study, a correlation between geodesy, geophysics and topography has been examined including the following variables: geological structure, coastal topography and bathymetry, geophysical fields, free-air gravity anomalies and geoid undulation, sediment thickness, bathymetric patterns, and extension of the transform faults. The variables were visualised on the high-resolution raster grids using Generic Mapping Tools (GMT) scripting toolset. The study area is located in the Seychelles and the Somali Sea segment of the Indian Ocean. The data incorporates satellite-derived gravity grid, EGM-2008, geological structures, topography from GEBCO grid and GlobSed sediment thickness, processed by GMT scripts. The results demonstrated that western continental slope of Somalia is wide, gently declining to the seafloor at depths exceeding -5000 m. Kenya and Tanzania present a wide continental foot with depths ranging from -3500 to -5000 m. The Somali Sea basin shows low sedimentation lower than 500 m, while ridges and island chains have higher sediment influx (1,000-2,000 m). The Mozambique Channel has dominating values at 2,500-3,500 m. Higher values are noted near the Reunion and Mauritius islands until the Seychelles via the Mascarene Plateau (500-1,000 m) against the <500 m in the areas of the Mid-Indian Ridge, Carlsberg Ridge and open water.
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Cordova, Muhammad Reza, and A'an J. Wahyudi. "MICROPLASTIC IN THE DEEP-SEA SEDIMENT OF SOUTHWESTERN SUMATRAN WATERS." Marine Research in Indonesia 41, no. 1 (June 21, 2016): 27–35. http://dx.doi.org/10.14203/mri.v41i1.99.
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Indonesia was recently ranked second on the list of countries producing plastic waste. Plastic can be degraded by thermal oxidation either with ultraviolet radiation and by mechanical to a very small size the size will be smaller. Degraded plastic with small sizes (<5 mm) measured has been micrometers known as microplastic. We took sediment samples on 07-18 May 2015 in EWIN 2015 cruise, which part of the contribution of Indonesian researchers for the International Indian Ocean Expedition-2 program, at 66.8 to 2182 m below sea level. Microplastic analysis from the sediment was carried out by using flotation methods. We found microplastic in 8 locations out of 10 sampling locations. We found 41 particles microplastic with a form of granules (35 particles) and fibers (6 particles). Most of microplastic particles were found at depths less than 500 m with 20 particles. The discovery of microplastic in the sediment from the sea of western Sumatra at a depth more than 2000 m, indicated that plastic, considered new developed materials (early nineteen centuries made), has invaded marine areas, including pristine areas. It confirms the statement that plastic waste has spread widely to different areas of the seas and oceans, including remote and mostly unknown areas such as the deep sea.
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Wijayananda, N. P., and D. S. Cronan. "The geochemistry and mineralogy of marine sediments from the eastern Indian Ocean." Marine Geology 117, no. 1-4 (March 1994): 275–85. http://dx.doi.org/10.1016/0025-3227(94)90020-5.
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Wall-Palmer, Deborah, Christopher W. Smart, Malcolm B. Hart, Melanie J. Leng, Mireno Borghini, Stefano Aliani, and Alessandra Conversi. "Late Pleistocene pteropods, heteropods and planktonic foraminifera from the Caribbean Sea, Mediterranean Sea and Indian Ocean." Micropaleontology 60, no. 6 (2014): 557–58. http://dx.doi.org/10.47894/mpal.60.6.05.
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Pteropods and heteropods (holoplanktonic gastropods) are an important component of the modern oceans; however, detailed information on their distribution in the fossil record is often based on poorly preserved specimens. This study presents the micropaleontological analysis of three exceptionally well-preserved Late Pleistocene marine sediment cores from the eastern Caribbean Sea, western Mediterranean Sea and the Indian Ocean. This study presents the first stratigraphical record of heteropods in the Caribbean Sea and extends the known zonation of pteropods in the Mediterranean Sea. Distributions of pteropods, heteropods and planktonic foraminifera are presented with abundance and species richness data, as well as stratigraphical dates inferred from the oxygen isotope stratigraphy, argon-argon dating and biostratigraphy. The findings of this study greatly improve our understanding of holoplanktonic gastropod stratigraphy and ecology. Results reveal that the geographical range of heteropods, thought to be restricted to sub-tropical warm waters, may be much greater, including waters of sub-polar temperature. Heteropods were also found to be surprisingly abundant, potentially representing a more important part of the ocean food web than previously thought. Analysis revealed two species of holoplanktonic gastropod that are previously undescribed and indicate that the pteropod Heliconoides mermuysi (Cahuzac and Janssen 2010), known exclusively from the Moulin de Cabanes (Miocene), may have lived in the Caribbean Sea and Indian Ocean as recently as 4 kyr ago. These findings highlight the urgent need for increased research on holoplanktonic gastropods. The threat that current climate change and ocean acidification poses, particularly to the delicately shelled forms, means that some species may become extinct before they have even been fully ‘discovered'.
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Pearson, Paul N., and Luke Penny. "Coiling directions in the planktonic foraminifer Pulleniatina: A complex eco-evolutionary dynamic spanning millions of years." PLOS ONE 16, no. 4 (April 13, 2021): e0249113. http://dx.doi.org/10.1371/journal.pone.0249113.
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Planktonic foraminifera are heterotrophic sexually reproducing marine protists with an exceptionally complete fossil record that provides unique insights into long-term patterns and processes of evolution. Populations often exhibit strong biases towards either right (dextral) or left (sinistral) shells. Deep-sea sediment cores spanning millions of years reveal that some species show large and often rapid fluctuations in their dominant coiling direction through time. This is useful for biostratigraphic correlation but further work is required to understand the population dynamical processes that drive these fluctuations. Here we address the case of coiling fluctuations in the planktonic foraminifer genus Pulleniatina based on new high-resolution counts from two recently recovered sediment cores from either side of the Indonesian through-flow in the tropical west Pacific and Indian Oceans (International Ocean Discovery Program Sites U1486 and U1483). We use single-specimen stable isotope analyses to show that dextral and sinistral shells from the same sediment samples can show significant differences in both carbon and oxygen isotopes, implying a degree of ecological separation between populations. In one case we detect a significant difference in size between dextral and sinistral specimens. We suggest that major fluctuations in coiling ratio are caused by cryptic populations replacing one another in competitive sweeps, a mode of evolution that is more often associated with asexual organisms than with the classical ‘biological species concept’.
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Southon, John, Mahyar Mohtadi, and Ricardo De Pol-Holz. "Planktonic Foram Dates from the Indonesian Arc: Marine 14C Reservoir Ages and a Mythical AD 535 Eruption of Krakatau." Radiocarbon 55, no. 3 (2013): 1164–72. http://dx.doi.org/10.1017/s0033822200048074.
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The Indonesian Arc represents the subduction of the Indian-Australian plate beneath Asia. It has been the scene of catastrophic tectonic activity, including the recent 2004 M=9.1 Aceh earthquake and resulting Indian Ocean tsunami. We have dated planktonic forams associated with historic tephras (Tambora, 1815 and Krakatau, 1883) in marine sediment cores to determine radiocarbon reservoir ages for 2 locations along the arc. Our best estimates for 19th century regional reservoir corrections (ΔR) are +90 ± 40 yr for surface-dwelling species and +220 ± 40 yr for mixed planktic assemblages containing some upper thermocline species, but scatter in the data suggests that past surface reservoir ages may have varied by about ±100 yr. We used the results of this study to investigate a proposed very large AD 535 eruption at or near Krakatau. We find no evidence for ash from such an eruption, and although this is negative evidence, we consider it sufficiently strong to rule out any possibility that one took place.
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Hahn, Annette, Enno Schefuß, Sergio Andò, Hayley C. Cawthra, Peter Frenzel, Martin Kugel, Stephanie Meschner, Gesine Mollenhauer, and Matthias Zabel. "Southern Hemisphere anticyclonic circulation drives oceanic and climatic conditions in late Holocene southernmost Africa." Climate of the Past 13, no. 6 (June 9, 2017): 649–65. http://dx.doi.org/10.5194/cp-13-649-2017.
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Abstract. Due to the high sensitivity of southern Africa to climate change, a reliable understanding of its hydrological system is crucial. Recent studies of the regional climatic system have revealed a highly complex interplay of forcing factors on precipitation regimes. This includes the influence of the tropical easterlies, the strength of the southern hemispheric westerlies as well as sea surface temperatures along the coast of the subcontinent. However, very few marine records have been available in order to study the coupling of marine and atmospheric circulation systems. Here we present results from a marine sediment core, recovered in shallow waters off the Gouritz River mouth on the south coast of South Africa. Core GeoB18308-1 allows a closer view of the last ∼ 4 kyr. Climate sensitive organic proxies, like the distribution and isotopic composition of plant-wax lipids as well as indicators for sea surface temperatures and soil input, give information on oceanographic and hydrologic changes during the recorded time period. Moreover, the micropaleontology, mineralogical and elemental composition of the sediments reflect the variability of the terrigenous input to the core site. The combination of down-core sediment signatures and a catchment-wide provenance study indicate that the Little Ice Age ( ∼ 300–650 cal yr BP) was characterized by climatic conditions favorable to torrential flood events. The Medieval Climate Anomaly ( ∼ 950–650 cal yr BP) is expressed by lower sea surface temperatures in the Mossel Bay area and humid conditions in the Gouritz River catchment. These new results suggest that the coincidence of humid conditions and cooler sea surface temperatures along the south coast of South Africa resulted from a strengthened and more southerly anticyclonic circulation. Most probably, the transport of moisture from the Indian Ocean by strong subtropical easterlies was coupled with Agulhas Bank upwelling pulses, which were initiated by an increase in Agulhas Current strength.
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Chadwick, Matthew, Claire S. Allen, Louise C. Sime, Xavier Crosta, and Claus-Dieter Hillenbrand. "Reconstructing Antarctic winter sea-ice extent during Marine Isotope Stage 5e." Climate of the Past 18, no. 1 (January 24, 2022): 129–46. http://dx.doi.org/10.5194/cp-18-129-2022.
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Abstract. Environmental conditions during Marine Isotope Stage (MIS) 5e (130–116 ka) represent an important “process analogue” for understanding the climatic responses to present and future anthropogenic warming. The response of Antarctic sea ice to global warming is particularly uncertain due to the short length of the observational record. Reconstructing Antarctic winter sea-ice extent during MIS 5e therefore provides insights into the temporal and spatial patterns of sea-ice change under a warmer-than-present climate. This study presents new MIS 5e records from nine marine sediment cores located south of the Antarctic Polar Front between 55 and 70∘ S. Winter sea-ice extent and sea-surface temperatures are reconstructed using marine diatom assemblages and a modern analogue technique transfer function, and changes in these environmental variables between the three Southern Ocean sectors are investigated. The Atlantic and East Indian sector records show much more variable MIS 5e winter sea-ice extent and sea-surface temperatures than the Pacific sector records. High variability in the Atlantic sector winter sea-ice extent is attributed to high glacial meltwater flux in the Weddell Sea, indicated by increased abundances of the diatom species Eucampia antarctica and Fragilariopsis cylindrus. The high variability in the East Indian sector winter sea-ice extent is conversely believed to result from large latitudinal migrations of the flow bands of the Antarctic Circumpolar Current, inferred from latitudinal shifts in the sea-surface temperature isotherms. Overall, these findings suggest that Pacific sector winter sea ice displays a low sensitivity to warmer climates. The different variability and sensitivity of Antarctic winter sea-ice extent in the three Southern Ocean sectors during MIS 5e may have significant implications for the Southern Hemisphere climatic system under future warming.
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Koho, K. A., K. G. J. Nierop, L. Moodley, J. J. Middelburg, L. Pozzato, K. Soetaert, J. van der Plicht, and G. J. Reichart. "Microbial bioavailability regulates organic matter preservation in marine sediments." Biogeosciences Discussions 9, no. 9 (September 24, 2012): 13187–210. http://dx.doi.org/10.5194/bgd-9-13187-2012.
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Abstract. Burial of organic matter (OM) plays an important role in marine sediments, linking the short-term, biological carbon cycle with the long-term, geological subsurface cycle. It is well established that low-oxygen conditions promote organic carbon burial in marine sediments. However, the mechanism remains enigmatic. Here we report biochemical quality, microbial degradability, OM preservation and accumulation along an oxygen gradient in the Indian Ocean. Our results show that more OM, and of biochemically higher quality, accumulates under low oxygen conditions. Nevertheless, microbial degradability does not correlate with the biochemical quality of OM. This decoupling of OM biochemical quality and microbial degradability, or bioavailability, violates the ruling paradigm that higher quality implies higher microbial processing. The inhibition of bacterial OM remineralisation may play an important role in the burial of organic matter in marine sediments and formation of oil source rocks.
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Koho, K. A., K. G. J. Nierop, L. Moodley, J. J. Middelburg, L. Pozzato, K. Soetaert, J. van der Plicht, and G.-J. Reichart. "Microbial bioavailability regulates organic matter preservation in marine sediments." Biogeosciences 10, no. 2 (February 20, 2013): 1131–41. http://dx.doi.org/10.5194/bg-10-1131-2013.
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Abstract. Burial of organic matter (OM) plays an important role in marine sediments, linking the short-term, biological carbon cycle with the long-term, geological subsurface cycle. It is well established that low-oxygen conditions promote organic carbon burial in marine sediments. However, the mechanism remains enigmatic. Here we report biochemical quality, microbial degradability, OM preservation and accumulation along an oxygen gradient in the Indian Ocean. Our results show that more OM, with biochemically higher quality, accumulates under low oxygen conditions. Nevertheless, microbial degradability does not correlate with the biochemical quality of OM. This decoupling of OM biochemical quality and microbial degradability, or bioavailability, violates the ruling paradigm that higher quality implies higher microbial processing. The inhibition of bacterial OM remineralisation may play an important role in the burial of organic matter in marine sediments and formation of oil source rocks.
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Matsuyama, Hidetoshi, Hideki Minami, Hirokazu Kasahara, Yoshihisa Kato, Masafumi Murayama, and Isao Yumoto. "Pseudoalteromonas arabiensis sp. nov., a marine polysaccharide-producing bacterium." International Journal of Systematic and Evolutionary Microbiology 63, Pt_5 (May 1, 2013): 1805–9. http://dx.doi.org/10.1099/ijs.0.043604-0.
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A novel exopolysaccharide-producing bacterium, designated strain k53T, was isolated from sediment from the Arabia Sea, Indian Ocean. The strain was Gram-negative, motile, strictly aerobic, oxidase-positive and catalase-positive, and required Na+ for growth. Its major isoprenoid quinone was ubiquinone-8 (Q-8), and its cellular fatty acid profile mainly consisted of C16 : 1ω7c, C16 : 0 and C18 : 1ω7c. The DNA G+C content was 43 mol%. 16S rRNA gene sequence analysis suggested that strain k53T is a member of the genus Pseudoalteromonas . Strain k53T exhibited close phylogenetic affinity to Pseudoalteromonas lipolytica LMEB 39T (98.0% 16S rRNA gene sequence similarity) and Pseudoalteromonas donghaensis HJ51T (97.3 %).The DNA–DNA reassociation values between strain k53T and P. lipolytica JCM 15903T and P. donghaensis LMG 24469T were 17 % and 12 %, respectively. Owing to the significant differences in phenotypic and chemotaxonomic characteristics, and phylogenetic analysis based on the 16S rRNA gene sequence and DNA–DNA relatedness data, the isolate merits classification as a representative of a novel species, for which the name Pseudoalteromonas arabiensis is proposed. The type strain of this species is k53T ( = JCM 17292T = NCIMB 14688T).
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Ziegler, M., L. J. Lourens, E. Tuenter, and G. J. Reichart. "Anomalously high Arabian Sea productivity conditions during MIS 13." Climate of the Past Discussions 5, no. 4 (July 27, 2009): 1989–2018. http://dx.doi.org/10.5194/cpd-5-1989-2009.
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Abstract. Marine isotope stage (MIS) 13 (~500 000 years ago) has been recognized as atypical in many paleoclimate records and, in particular, it has been connected to an exceptionally strong summer monsoon in East Asia. Here we present a multi-proxy study of a sediment core taken from the Murray Ridge at intermediate water depth in the northern Arabian Sea that covers the last 750 000 years. Our results indicate that upwelling driven primary productivity conditions were anomalously high during MIS 13 and led to extreme carbonate dissolution and glauconitization. We argue that an extreme summer monsoon circulation was probably not responsible for these aberrant conditions, because such an event does not show up in the Antarctic methane record and transient modeling results. As an alternative, we propose that high productivity was related to the onset of an intensive meridional overturning circulation in the Atlantic Ocean at the end of the Mid-Pleistocene transition. This led to an increased supply of nutrient-rich deep waters into the Indian Ocean euphotic zone, thereby triggering the observed productivity maximum.
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MacLeod, Norman. "Punctuated anagenesis and the importance of stratigraphy to paleobiology." Paleobiology 17, no. 2 (1991): 167–88. http://dx.doi.org/10.1017/s0094837300010472.
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The depositional history of Upper Miocene through Recent sediments from DSDP Site 214 (Ninetyeast Ridge, Indian Ocean) is reexamined. Samples of the Globorotalia tumida planktic foraminiferal lineage, originally obtained from these sediments by Malmgren et al. (1983), serve as the empirical basis for the recognition of punctuated anagenesis as a distinct mode of phenotypic evolution and have been the subject of numerous additional investigations. However, conclusions reached by previous authors depend strictly on the validity of the original chronostratigraphic interpretation of these sediments. Graphic correlation analysis of first- and last-appearance datum levels for a total of 41 planktic foraminiferal, radiolarian, and calcareous nannoplankton taxa provides evidence for a more complex depositional history at this deep-sea site than originally believed. Based on a conservative model of variation in the pattern of sediment accumulation rates, the lowermost portion of the studied section (6.5-4.3 Ma) represents an interval of temporally condensed sediment accumulation (1.88 cm/1,000 yr) followed by an interval (4.3-2.8 Ma) of temporally expanded sediment accumulation (3.97 cm/1,000 yr). This interval, in turn, is followed by a depositional hiatus or an extremely condensed interval, at least 800,000 yr in duration, which is followed by another relatively condensed (1.36 cm/1,000 yr) interval from 2.0 Ma-Recent. Although this chronostratigraphic reinterpretation deviates substantially from the original, which recognized Site 214 as being both temporally continuous and exhibiting a constant sediment accumulation rate from the Upper Miocene through the Upper Pliocene, it is more consistent with expectations based on Neogene eustatic sea-level fluctuations and global surveys of Neogene hiatus distributions. Age assignments for samples of the Gr. tumida lineage based on the revised chronostratigraphic model reverse some findings of previous investigators with respect to the distinctiveness of phenotypic evolutionary rates characterizing the transition from Gr. plesiotumida to Gr. tumida. Finally, a brief survey of similar marine invertebrate lineage studies shows that changes in the rate of phenotypic evolution often appear to coincide with major physical changes in the paleoceanographic environment. Such correspondences may be due, at least in part, to the effect of these environmental changes on sediment accumulation rates. Paleobiologists who seek to understand patterns of phenotypic change over time must remove the effects of variations in sediment accumulation rates from their data before evolutionary hypothesis testing and remain aware of the limitations imposed on their interpretations by the uncertain nature of chronostratigraphic inference.
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Garzanti, Eduardo, Giovanni Vezzoli, Sergio Andò, Mara Limonta, Laura Borromeo, and Christian France-Lanord. "Provenance of Bengal Shelf Sediments: 2. Petrology and Geochemistry of Sand." Minerals 9, no. 10 (October 19, 2019): 642. http://dx.doi.org/10.3390/min9100642.
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The Bangladesh lowlands are traversed by the largest sediment flux on the planet. Detritus generated mostly in Himalayan highlands and conveyed through the Ganga–Brahmaputra rivers and Meghna estuary reaches the Bay of Bengal, where it forms a composite deltaic system. This study integrates the vast existing database on Ganga–Brahmaputra sediments of all grain sizes from clay to sand with new petrographic, mineralogical, and geochemical data on estuarine and shallow-marine sands. A large spectrum of compositional signatures was used to: (i) assess the relative supply of the Ganga and Brahmaputra rivers to estuarine and shelfal sediments; (ii) define the compositional variability of estuarine sediments and the impact exerted by hydraulic sorting and climate-related chemical weathering on provenance signals; (iii) define the compositional variability of shelf sediments and the potential hydrodynamic segregation of fast-settling heavy minerals in coastal environments and of slow-settling platy micas on low-energy outer-shelf floors; (iv) consider the potential additional mud supply from the western subaerial part of the delta formerly built by the Ganga River; and (v) draw a preliminary mineralogical comparison between fluvio-deltaic sediments and turbidites of the Bengal–Nicobar deep-sea fan, thus tracing sediment dispersal across the huge sedimentary system extending from Tibet to the equatorial Indian Ocean. All investigated mineralogical and geochemical parameters, as well as Sr and Nd isotope ratios and clay–mineral assemblages, showed a clear prevalence in sediment supply from the Brahmaputra (60–70%) over the Ganga (30–40%). Heavy-mineral suites and Sr and Nd isotope fingerprints of Bengal shelf sediments are nearly identical to those of the Brahmaputra River and Meghna estuary, also because the Brahmaputra carries almost twice as many Ca-plagioclase grains and heavy minerals including epidote than the Ganga, and these minerals control the large majority of the Sr and Nd budgets. The experience gained in modern settings can be directly extrapolated only to the recent past, because sediments older than the late Pleistocene and buried more than a few hundred meters begin to lose less durable ferromagnesian minerals by selective chemical dissolution, which makes quantitative estimates progressively less robust in more deeply buried older strata.
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Jiang, Zhao, Chang-Guo Yuan, Min Xiao, Xin-Peng Tian, Inam-Ullah Khan, Chang-Jin Kim, Xiao-Yang Zhi, and Wen-Jun Li. "Abyssicoccus albus gen. nov., sp. nov., a novel member of the family Staphylococcaceae isolated from marine sediment of the Indian Ocean." Antonie van Leeuwenhoek 109, no. 8 (June 7, 2016): 1153–60. http://dx.doi.org/10.1007/s10482-016-0717-2.
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Woodall, Lucy C., Anna Sanchez-Vidal, Miquel Canals, Gordon L. J. Paterson, Rachel Coppock, Victoria Sleight, Antonio Calafat, Alex D. Rogers, Bhavani E. Narayanaswamy, and Richard C. Thompson. "The deep sea is a major sink for microplastic debris." Royal Society Open Science 1, no. 4 (December 2014): 140317. http://dx.doi.org/10.1098/rsos.140317.
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Marine debris, mostly consisting of plastic, is a global problem, negatively impacting wildlife, tourism and shipping. However, despite the durability of plastic, and the exponential increase in its production, monitoring data show limited evidence of concomitant increasing concentrations in marine habitats. There appears to be a considerable proportion of the manufactured plastic that is unaccounted for in surveys tracking the fate of environmental plastics. Even the discovery of widespread accumulation of microscopic fragments (microplastics) in oceanic gyres and shallow water sediments is unable to explain the missing fraction. Here, we show that deep-sea sediments are a likely sink for microplastics. Microplastic, in the form of fibres, was up to four orders of magnitude more abundant (per unit volume) in deep-sea sediments from the Atlantic Ocean, Mediterranean Sea and Indian Ocean than in contaminated sea-surface waters. Our results show evidence for a large and hitherto unknown repository of microplastics. The dominance of microfibres points to a previously underreported and unsampled plastic fraction. Given the vastness of the deep sea and the prevalence of microplastics at all sites we investigated, the deep-sea floor appears to provide an answer to the question— where is all the plastic?
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Nugroho, Septriono Hari, Yahdi Zaim, Eko Yulianto, Yan Rizal, Anis Kurniasih, Purna Sulastya Putra, Singgih Prasetyo Adi Wibowo, and Amar Amar. "A Preliminary Study In Vertical Distribution Of Planktonic Foraminifera And Marine Ecological Conditions Of Simeulue Sub-Basin, Aceh, Indonesia." Bulletin Of The Geological Society Of Malaysia 72 (November 15, 2021): 137–49. http://dx.doi.org/10.7186/bgsm72202111.
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A marine sediment core EW17-09 (03˚ 28’358” latitude and 96˚ 18’788” longitude, 870 m water depth, 390 cm core length) was retrieved from the western Sumatra, Simeulue sub-basin, Indonesia. Simeulue sub-basin are situated in eastern Indian Ocean, western part of Aceh Province, which is one of the outer islands in Indonesia. This sub-basin is influenced by adjacent lands in response to tectonic and climate dynamics. The dynamics of marine ecological conditions in the past is an urgent need for providing an analogy to the changes in the future conditions. In this study, the ecological conditions were examined by identifying the vertical distribution of planktonic foraminifera assemblages. This preliminary study demonstrated the presence of Globigerinoides ruber, Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, Globigerina calida calida, Globigerinoides elongates, Globigerinoides cyclostomus and Globigerinoides sacculiferus in the samples. The assemblages indicate warm water conditions prevailed in the Simeulue sub-basin during the deposition of the samples. However, subtle ecological changes might have occurred in response to the dynamic of thermocline layer. Cluster analysis of planktonic foraminifera abundance and diversity resulted in three groups showing different ecological conditions. Warm water conditions, high salinity, deeper thermocline with moderate sedimentation disturbance prevailed during the deposition of lower part of the core. Oligotropic water conditions with higher temperature, lower salinity, shallower thermocline layer, and moderate sedimentation disturbance predominated during the deposition of the middle part of the core. The paleooceanography conditions of the upper part of the core are comparable to the lower part. Nevertheless, there are a shoaling of the thermocline in the end of the period. These conditions may indicate an increase in upwelling fluctuations and may represent a change in the IOD-like mean state of the Indian Ocean.
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SEARLE, MIKE, RICHARD I. CORFIELD, BEN STEPHENSON, and JOE MCCARRON. "Structure of the North Indian continental margin in the Ladakh–Zanskar Himalayas: implications for the timing of obduction of the Spontang ophiolite, India–Asia collision and deformation events in the Himalaya." Geological Magazine 134, no. 3 (May 1997): 297–316. http://dx.doi.org/10.1017/s0016756897006857.
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The collision of India and Asia can be defined as a process that started with the closing of the Tethyan ocean that, during Mesozoic and early Tertiary times, separated the two continental plates. Following initial contact of Indian and Asian continental crust, the Indian plate continued its northward drift into Asia, a process which continues to this day. In the Ladakh–Zanskar Himalaya the youngest marine sediments, both in the Indus suture zone and along the northern continental margin of India, are lowermost Eocene Nummulitic limestones dated at ∼54 Ma. Along the north Indian shelf margin, southwest-facing folded Palaeocene–Lower Eocene shallow-marine limestones unconformably overlie highly deformed Mesozoic shelf carbonates and allochthonous Upper Cretaceous shales, indicating an initial deformation event during the latest Cretaceous–early Palaeocene, corresponding with the timing of obduction of the Spontang ophiolite onto the Indian margin. It is suggested here that all the ophiolites from Oman, along western Pakistan (Bela, Muslim Bagh, Zhob and Waziristan) to the Spontang and Amlang-la ophiolites in the Himalaya were obducted during the late Cretaceous and earliest Palaeocene, prior to the closing of Tethys.The major phase of crustal shortening followed the India–Asia collision producing spectacular folds and thrusts across the Zanskar range. A new structural profile across the Indian continental margin along the Zanskar River gorge is presented here. Four main units are separated by major detachments including both normal faults (e.g. Zanskar, Karsha Detachments), southwest-directed thrusts reactivated as northeast-directed normal faults (e.g. Zangla Detachment), breakback thrusts (e.g. Photoksar Thrust) and late Tertiary backthrusts (e.g. Zanskar Backthrust). The normal faults place younger rocks onto older and separate two units, both showing compressional tectonics, but have no net crustal extension across them. Rather, they are related to rapid exhumation of the structurally lower, middle and deep crustal metamorphic rocks of the High Himalaya along the footwall of the Zanskar Detachment. The backthrusting affects the northern margin of the Zanskar shelf and the entire Indus suture zone, including the mid-Eocene–Miocene post-collisional fluvial and lacustrine molasse sediments (Indus Group), and therefore must be Pliocene–Pleistocene in age. Minimum amounts of crustal shortening across the Indian continental margin are 150–170 km although extreme ductile folding makes any balancing exercise questionable.
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Rixen, T., A. Baum, B. Gaye, and B. Nagel. "Seasonal and interannual variations in the nitrogen cycle in the Arabian Sea." Biogeosciences 11, no. 20 (October 16, 2014): 5733–47. http://dx.doi.org/10.5194/bg-11-5733-2014.
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Abstract. The Arabian Sea plays an important role in the marine nitrogen cycle because of its pronounced mid-water oxygen minimum zone (OMZ) in which bio-available nitrate (NO3−) is reduced to dinitrogen gas (N2). As the nitrogen cycle can respond fast to climate-induced changes in productivity and circulation, the Arabian Sea sediments are an important palaeoclimatic archive. In order to understand seasonal and interannual variations in the nitrogen cycle, nutrient data were obtained from the literature published prior to 1993, evaluated, and compared with data measured during five expeditions carried out in the framework of the Joint Global Ocean Flux Study (JGOFS) in the Arabian Sea in 1995 and during a research cruise of RV Meteor in 2007. The data comparison showed that the area characterized by a pronounced secondary nitrite maximum (SNM) was by 63% larger in 1995 than a similarly determined estimate based on pre-JGOFS data. This area, referred to as the core of the denitrifying zone, showed strong seasonal and interannual variations driven by the monsoon. During the SW monsoon, the SNM retreated eastward due to the inflow of oxygen-enriched Indian Ocean Central Water (ICW). During the NE monsoon, the SNM expanded westward because of the reversal of the current regime. On an interannual timescale, a weaker SW monsoon decreased the inflow of ICW from the equatorial Indian Ocean and increased the accumulation of denitrification tracers by extending the residence time of water in the SNM. This is supported by palaeoclimatic studies showing an enhanced preservation of accumulative denitrification tracers in marine sediments in conjunction with a weakening of the SW monsoon during the late Holocene.
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Gopalakrishnan, Sumitha. "Distribution of Cultivable Actinobacteria from the Marine Sediments along the Andaman Coast of Eastern Indian Ocean." Advances in Animal and Veterinary Sciences 2, no. 12 (2014): 668–82. http://dx.doi.org/10.14737/journal.aavs/2014/2.12.668.682.
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Laureillard, J., L. Pinturier, J. Fillaux, and A. Saliot. "Organic geochemistry of marine sediments of the Subantarctic Indian Ocean sector: Lipid classes—sources and fate." Deep Sea Research Part II: Topical Studies in Oceanography 44, no. 5 (January 1997): 1085–108. http://dx.doi.org/10.1016/s0967-0645(96)00111-7.
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Ooms, Marijke, Bart van de Vijver, Stijn Temmerman, and Louis Beyens. "A Holocene palaeoenviromental study of a sediment core from Ile de la Possession, Iles Crozet, sub-Antarctica." Antarctic Science 23, no. 5 (April 15, 2011): 431–41. http://dx.doi.org/10.1017/s0954102011000277.
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AbstractIle de la Possession is one of the few islands in the southern Indian Ocean, making the island a valuable place to reconstruct past environmental and climatic changes. In this study a peat sediment core was analysed to reconstruct the changes that occurred before, during and after the eruption of the Morne Rouge (10 000–5500 14C yr bp) volcano. In addition to sedimentological analyses, diatom communities were used to reconstruct humidity and altitude, based on existing transfer functions. Radiocarbon dating of a tephra layer showed that the Morne Rouge volcano erupted between 6700–6600 cal. yr bp, giving a much more precise time scale for this event. The eruption was preceded by a tsunami flooding, indicated by the high numbers of marine diatoms found immediately before the tephra layer. After the eruption pioneer diatom species recolonized the coring site. Evidence is presented of the late climatic optimum around 3050 cal. yr bp, preceded by a cooling event until 6600 cal. yr bp. Nutrient input from elephant seals and wandering albatrosses obscured the climate signal for the last 600 cal yr bp.
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Ziegler, M., L. J. Lourens, E. Tuenter, and G. J. Reichart. "High Arabian Sea productivity conditions during MIS 13 – odd monsoon event or intensified overturning circulation at the end of the Mid-Pleistocene transition?" Climate of the Past 6, no. 1 (January 29, 2010): 63–76. http://dx.doi.org/10.5194/cp-6-63-2010.
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Abstract. Marine isotope stage (MIS) 13 (~500 000 years ago) has been recognized as atypical in many paleoclimate records and, in particular, it has been connected to an exceptionally strong summer monsoon throughout the Northern Hemisphere. Here, we present a multi-proxy study of a sediment core taken from the Murray Ridge at an intermediate water depth in the northern Arabian Sea that covers the last 750 000 years. Our results indicate that primary productivity conditions were anomalously high during MIS 13 in the Arabian Sea and led to extreme carbonate dissolution and glauconitization in the deep-sea sediments. These observations could be explained by increased wind driven upwelling of nutrient-rich deep waters and, hence, by the occurrence of an exceptionally strong summer monsoon event during MIS 13, as it was suggested in earlier studies. However, ice core records from Antarctica demonstrate that atmospheric methane concentrations, which are linked to the extent of tropical wetlands, were relatively low during this period. This constitutes a strong argument against an extremely enhanced global monsoon circulation during MIS 13 which, moreover, is in contrast with results of transient climate modelling experiments. As an alternative solution for the aberrant conditions in the Arabian Sea record, we propose that the high primary productivity was probably related to the onset of an intensive meridional overturning circulation in the Atlantic Ocean at the end of the Mid-Pleistocene transition. This may have led to an increased supply of nutrient-rich deep waters into the Indian Ocean euphotic zone, thereby triggering the observed productivity maximum.
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Horigome, M. T., P. Ziveri, M. Grelaud, K. H. Baumann, G. Marino, and P. G. Mortyn. "Environmental controls on the <i>Emiliania huxleyi</i> calcite mass." Biogeosciences Discussions 10, no. 6 (June 10, 2013): 9285–313. http://dx.doi.org/10.5194/bgd-10-9285-2013.
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Abstract. Although ocean acidification is expected to impact (bio)calcification by decreasing the seawater carbonate ion concentration, [CO32−], there exists evidence of non-uniform response of marine calcifying plankton to low seawater [CO32−]. This raises questions on the role of environmental factors other than acidification and on the complex physiological responses behind calcification. Here we investigate the synergistic effect of multiple environmental parameters, including temperature, nutrient (nitrate and phosphate) availability, and seawater carbonate chemistry on the coccolith calcite mass of the cosmopolitan coccolithophore Emiliania huxleyi, the most abundant species in the world ocean. We use a suite of surface (late Holocene) sediment samples from the South Atlantic and southwestern Indian Ocean taken from depths lying well above the modern lysocline. The coccolith calcite mass in our results presents a latitudinal distribution pattern that mimics the main oceanographic features, thereby pointing to the potential importance of phosphorus and temperature in determining coccolith mass by affecting primary calcification and possibly driving the E. huxleyi morphotype distribution. This evidence does not necessarily argue against the potentially important role of the rapidly changing seawater carbonate chemistry in the future, when unabated fossil fuel burning will likely perturb ocean chemistry beyond a critical point. Rather our study highlights the importance of evaluating the combined effect of several environmental stressors on calcifying organisms to project their physiological response(s) in a high CO2 world and improve interpretation of paleorecords.
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Horigome, M. T., P. Ziveri, M. Grelaud, K. H. Baumann, G. Marino, and P. G. Mortyn. "Environmental controls on the <i>Emiliania huxleyi</i> calcite mass." Biogeosciences 11, no. 8 (April 24, 2014): 2295–308. http://dx.doi.org/10.5194/bg-11-2295-2014.
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Abstract. Although ocean acidification is expected to impact (bio) calcification by decreasing the seawater carbonate ion concentration, [CO32−], there is evidence of nonuniform response of marine calcifying plankton to low seawater [CO32−]. This raises questions about the role of environmental factors other than acidification and about the complex physiological responses behind calcification. Here we investigate the synergistic effect of multiple environmental parameters, including seawater temperature, nutrient (nitrate and phosphate) availability, and carbonate chemistry on the coccolith calcite mass of the cosmopolitan coccolithophore Emiliania huxleyi, the most abundant species in the world ocean. We use a suite of surface (late Holocene) sediment samples from the South Atlantic and southwestern Indian Ocean taken from depths lying above the modern lysocline (with the exception of eight samples that are located at or below the lysocline). The coccolith calcite mass in our results presents a latitudinal distribution pattern that mimics the main oceanographic features, thereby pointing to the potential importance of seawater nutrient availability (phosphate and nitrate) and carbonate chemistry (pH and pCO2) in determining coccolith mass by affecting primary calcification and/or the geographic distribution of E. huxleyi morphotypes. Our study highlights the importance of evaluating the combined effect of several environmental stressors on calcifying organisms to project their physiological response(s) in a high-CO2 world and improve interpretation of paleorecords.
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Sirocko, Frank, Michael Sarnthein, Heinz Lange, and Helmut Erlenkeuser. "Atmospheric summer circulation and coastal upwelling in the Arabian Sea during the Holocene and the last glaciation." Quaternary Research 36, no. 1 (July 1991): 72–93. http://dx.doi.org/10.1016/0033-5894(91)90018-z.
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AbstractAccumulation rates of biogenic and lithogenic components were studied in 39 turbidite-free, well-dated sediment cores from the northern Indian Ocean to define the proportions of fluvial and eolian input and to reconstruct Quaternary patterns of coastal upwelling. The majority of dust deposited in the western Arabian Sea during the Holocene (about 100 × 106t yr−1) is advected from Arabia by northwesterly winds, which overlie the low-level southwest monsoon. The glacial increase in dust flux to 160 × 106t yr−1 culminated in the northern Arabian Sea, most probably due to (i) entrainment of dust, rich in chlorite, dolomite, and lithogenic carbonate in the then-dry Persian Gulf, and (ii) a southward shift of the mean position of the southwest monsoon during glacial summer. This shift is recorded in reduced accumulation rates of biogenic opal and increased rates of marine carbonate off Somalia and Oman. Both the terrigenous and biogenic sediment records show that the northwesterly winds and the southwest monsoon persisted over the last 27,000 yr, as well as the Asian continental summer heat low. However, the glacial seasonal time span of the southwest monsoon season was much reduced, most likely because of a delay in the seasonal onset of the southwest monsoon.
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Lai, Qiliang, Yuanyuan Fu, Jianning Wang, Shuangxi Chen, Huanzi Zhong, Fengqin Sun, and Zongze Shao. "Citreicella marina sp. nov., isolated from deep-sea sediment." International Journal of Systematic and Evolutionary Microbiology 61, no. 4 (April 1, 2011): 728–31. http://dx.doi.org/10.1099/ijs.0.022376-0.
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A taxonomic study was carried out on a novel strain, designated CK-I3-6T, which was isolated from deep-sea sediment of the south-west Indian Ocean Ridge. Cells were Gram-reaction-negative, oxidase- and catalase-positive, rod-shaped and non-motile. Growth was observed at 4–38 °C and in 1–12 % (w/v) NaCl. Cells were able to degrade gelatin and oxidize thiosulfate but did not reduce nitrate. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CK-I3-6T belonged to the genus Citreicella with a sequence similarity of 97.3 % to Citreicella thiooxidans CHLG 1T, while similarities with other taxa were <95.7 %. DNA–DNA hybridization showed that strain CK-I3-6T and C. thiooxidans CHLG 1T showed a low DNA–DNA relatedness (48±3 %). The principal fatty acids were C16 : 0 (7.8 %), C18 : 1ω7c (66.6 %), summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c; 6.3 %) and C19 : 0ω8c cyclo (10.0 %). The chromosomal DNA G+C content was 67.5 mol%. On the basis of the combined genotypic and phenotypic data, strain CK-I3-6T represents a novel species of the genus Citreicella, for which the name Citreicella marina sp. nov. is proposed. The type strain is CK-I3-6T ( = CCTCC AB 209064T = LMG 25230T = MCCC 1A03060T).