Data

 

34 datasets found! (Query time: 15 ms)

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1. Thomas, AL; Fujita, K; Iryu, Y et al. (2012): Isotope analysis, age calculation and calcite concentration from IODP Hole 310-M0005D

   Abstract:

   We present uranium-thoriumchronology for a 102 mcore through a Pleistocene reef at Tahiti (French Polynesia) sampled during IODP Expedition 310 "Tahiti Sea Level". We employ total and partial dissolution procedures on the older coral samples to investigate the diagenetic overprint of the uranium-thoriumsystem. Although alteration of the U-Th system cannot be robustly corrected, diagenetic trends in the U-Th data, combined with sea level and subsidence constraints for the growth of the corals enables the age of critical samples to be constrained to marine isotope stage 9. We use the ages of the corals, together with d18O based sea-level histories, to provide maximum constraints on possible paleo water-depths. These depth constraints are then compared to independent depth estimates based on algal and foraminiferal assemblages, microbioerosion patterns, and sedimentary facies, confirming the accuracy of these paleo water-depth estimates. […]

   Size:

   2 datasets

   https://doi.org/10.1594/PANGAEA.787783 - Score: 9.075
2. Asami, R; Felis, T; Deschamps, P et al. (2009): Stable oxygen isotope record and Sr/Ca ratios of corals from IODP Holes M0009D and M0023A

   Abstract:

   We present monthly resolved records of strontium/calcium (Sr/Ca) and oxygen isotope (d18O) ratios from well-preserved fossil corals drilled during the Integrated Ocean Drilling Program (IODP) Expedition 310 'Tahiti Sea Level' and reconstruct sea surface conditions in the central tropical South Pacific Ocean during two time windows of the last deglaciation. The two Tahiti corals examined here are uranium/thorium (U/Th)-dated at 12.4 and 14.2 ka, which correspond to the Younger Dryas (YD) cold reversal and the Bølling-Allerød (B-A) warming of the Northern Hemisphere, respectively. The coral Sr/Ca records indicate that annual average sea surface temperature (SST) was 2.6-3.1 °C lower at 12.4 ka and 1.0-1.6 °C lower at 14.2 ka relative to the present, with no significant changes in the amplitude of the seasonal SST cycle. […]

   Size:

   2 datasets

   https://doi.org/10.1594/PANGAEA.736807 - Score: 8.81
3. Seard, C; Camoin, G; Yokoyama, Y et al. (2011): Age analysis, aragonite and high magnesium calcite content from different IODP Holes from Exp 310

   Abstract:

   The widespread occurrence of microbialites in the last deglacial reef frameworks (16-6 Ka BP) implies that the accurate study of their development patterns is of prime importance to unravel the evolution of reef architecture through time and to reconstruct the reef response to sea-level variations and environmental changes. The present study is based on the sedimentological and chronological analysis (14C AMS dating) of drill cores obtained during the IODP Expedition #310 "Tahiti Sea Level" on the successive terraces which typify the modern reef slopes from Tahiti. It provides a comprehensive data base to investigate the microbialite growth patterns (i.e. growth rates and habitats), to analyze their roles in reef frameworks and to reconstruct the evolution of the reef framework architecture during sea-level rise. […]

   Size:

   4 datasets

   https://doi.org/10.1594/PANGAEA.767366 - Score: 8.76
4. Fujita, K; Omori, A; Yokoyama, Y et al. (2010): Benthic foraminifera and sea level analyses from IODP Hole 310-M0005D

   Abstract:

   The course of sea-level fluctuations during Termination II (TII; the penultimate deglaciation), which is critical for understanding ice-sheet dynamics and suborbital climate variability, has yet to be established. This is partly because most shallow-water sequences encompassing TII were eroded during sea-level lowstands of the last glacial period or were deposited below the present sea level. Here we report a new sequence recording sea-level changes during TII in the Pleistocene sequence at Hole M0005D (water depth: 59.63 m below sea level [mbsl]) off Tahiti, French Polynesia, which was drilled during Integrated Ocean Drilling Program Expedition 310. Lithofacies variations and stratigraphic changes in the taxonomic composition, preservation states, and intraspecific test morphology of large benthic foraminifers indicate a deepening-upward sequence in the interval from Core 310-M0005D-26R (core depth: 134 mbsl) through -16R (core depth: 106 mbsl). […]

   Size:

   3 datasets

   https://doi.org/10.1594/PANGAEA.763766 - Score: 8.76
5. Felis, T; Merkel, U; Asami, R et al. (2012): Monthly Tahiti coral Sr/Ca and oxygen isotope data from IODP Hole 310-M0024A

   Abstract:

   The early last glacial termination was characterized by intense North Atlantic cooling and weak overturning circulation. This interval between ~18,000 and 14,600 years ago, known as Heinrich Stadial 1, was accompanied by a disruption of global climate and has been suggested as a key factor for the termination. However, the response of interannual climate variability in the tropical Pacific (El Niño-Southern Oscillation) to Heinrich Stadial 1 is poorly understood. Here we use Sr/Ca in a fossil Tahiti coral to reconstruct tropical South Pacific sea surface temperature around 15,000 years ago at monthly resolution. Unlike today, interannual South Pacific sea surface temperature variability at typical El Niño-Southern Oscillation periods was pronounced at Tahiti. Our results indicate that the El Niño-Southern Oscillation was active during Heinrich Stadial 1, consistent with climate model simulations of enhanced El Niño-Southern Oscillation variability at that time. […]

   Size:

   1068 data points

   https://doi.org/10.1594/PANGAEA.786743 - Score: 8.25
6. Westphal, H; Heindel, K; Brandano, M et al. (2012): (Table 1) Different age analysis from IODP Site 310-M0018A

   Abstract:

   Deglacial reefs from Tahiti (IODP 310) feature a co-occurrence of zooxanthellate corals with microbialites that compose up to 80 vol% of the reef framework. The notion that microbialites tend to form in more nutrient-rich environments has previously led to the concept that such encrustations are considerably younger than the coral framework, and that they have formed in deeper storeys of the reef edifice, or that they represent severe disturbances of the reef ecosystem. As indicated by their repetitive interbedding with coralline red algae, the microbialites of this reef succession of Tahiti, however, formed immediately after coral growth under photic conditions. Clearly, the deglacial reef microbialites present in the IODP 310 cores did not follow disturbances such as drowning or suffocation by terrestrial material, and are not "disaster forms". […]

   Size:

   13 data points

   https://doi.org/10.1594/PANGAEA.788488 - Score: 8.25
7. Iryu, Y; Takahashi, Y; Fujita, K et al. (2012): Nongeniculate coralline algae from IODP Site 310-M0005D

   Abstract:

   Material cored during the Integrated Ocean Drilling Program (IODP) Expedition 310 'Tahiti Sea Level' revealed that the fossil reef systems around Tahiti are composed of two major stratigraphic sequences: (i) a last deglacial sequence; and (ii) an older Pleistocene sequence. The older Pleistocene carbonate sequence is composed of reef deposits associated with volcaniclastic sediments and was preserved in Hole 310-M0005D drilled off Maraa. Within an approximately 70-m-thick older Pleistocene sequence (33.22-101.93 m below seafloor; 92.85-161.56 m below present sealevel) in this hole, 11 depositional units are defined by lithological changes, sedimentological features, and paleontological characteristics and are numbered sequentially from the top of the hole downward (Subunits P1-P11). […]

   Size:

   494 data points

   https://doi.org/10.1594/PANGAEA.788464 - Score: 8.204
8. DeLong, K; Quinn, TM; Shen, CC et al. (2012): (Table A1) Uranium and Thorium determination from IODP Site 310-M0007B

   Abstract:

   The Integrated Ocean Drilling Program (IODP) Expedition 310 recovered drill cores from the drowned reefs around the island of Tahiti (17°40'S, 149°30'W), many of which contained samples of massive corals from the genus Porites. Herein we report on one well-preserved fossil coral sample: a 13.6 cm long Porites sp. dated by uranium series techniques at 9523 ± 33 years. Monthly delta18O and Sr/Ca determinations reveal nine clear and robust annual cycles. Coral delta18O and Sr/Ca determinations estimate a mean temperature of ca. 24.3°C (ca. 3.2°C colder than modern) for Tahiti at 9.5 ka; however, this estimate is viewed with caution since potential sources of cold bias in coral geochemistry remain to be resolved. The interannual variability in coral delta18O is similar between the 9.5 ka coral record and a modern record from nearby Moorea. The seasonal cycle in coral Sr/Ca is approximately the same or greater in the 9.5 ka coral record than in modern coral records from Tahiti. […]

   Size:

   18 data points

   https://doi.org/10.1594/PANGAEA.788536 - Score: 8.15
9. Hathorne, EC; Felis, T; James, RH et al. (2011): Geochemical data for drilled powder samples from two fossil Porites corals from Integrated Ocean Drilling Program Expedition 310

   Abstract:

   Fossil corals are unique archives of past seasonal climate variability, providing vital information about seasonal climate phenomena such as ENSO and monsoons. However, submarine diagenetic processes can potentially obscure the original climate signals and lead to false interpretations. Here we demonstrate the potential of laser ablation ICP-MS to rapidly detect secondary aragonite precipitates in fossil Porites colonies recovered by Integrated Ocean Drilling Program (IODP) Expedition 310 from submerged deglacial reefs off Tahiti. High resolution (100 µm) measurements of coralline B/Ca, Mg/Ca, S/Ca, and U/Ca ratios are used to distinguish areas of pristine skeleton from those afflicted with secondary aragonite. Measurements of coralline Sr/Ca, U/Ca and oxygen isotope ratios, from areas identified as pristine, reveal that the seasonal range of sea surface temperature in the tropical south Pacific during the last deglaciation (14.7 and 11 ka) was similar to that of today.

   Size:

   1038 data points

   https://doi.org/10.1594/PANGAEA.756560 - Score: 8.15
10. Inoue, M; Yokoyama, Y; Harada, M et al. (2010): (Table 1) Trace element and age analysis from the Porites coral from IODP Exp 310

    Abstract:

    Climate responses and changes in marine environments during the last deglaciation have been controversial and few paleoceanographic data are available from the tropical South Pacific, though this region is crucial in the investigations of ocean-atmosphere interactions. Integrated Ocean Drilling Program Expedition 310 was conducted to establish the time course of the postglacial sea-level rise at Tahiti in the South Pacific. A principal objective of this expedition was to examine the variation of marine environments during the last deglaciation. As fossil Porites coral is ideal for assessing past marine environments, we selected only Porites specimens from the many coral specimens retrieved, examined them by XRD, and dated them by the 14C method. In all, we obtained 17 pristine Porites specimens composed of only aragonite with ages from 15 to 9 ka. Then, we measured Mg/Ca, Ba/Ca, and U/Ca ratios and Cd contents as proxies for upwelling and sea surface temperature. […]

    Size:

    203 data points

    https://doi.org/10.1594/PANGAEA.763824 - Score: 8.15

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