Linsley, Braddock K; von Breymann, Marta T (1991): Stable isotope and geochemical record of ODP Hole 124-769A [dataset publication series]. PANGAEA, https://doi.org/10.1594/PANGAEA.762113, Supplement to: Linsley, BK; von Breymann, MT (1991): Stable isotopic and geochemical record in the Sulu Sea during the lats 750 ky: assessment of surface water variability and paleoproductivity changes. In: Silver, EA; Rangin, C; von Breymann, MT; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 124, 379-396, https://doi.org/10.2973/odp.proc.sr.124.151.1991
Always quote citation above when using data! You can download the citation in several formats below.
Abstract:
Deep marine late Pleistocene sediments from Ocean Drilling Program Sulu Sea Site 769 contain a high-resolution record of paleoceanographic change in this strongly monsoonal climatic setting in the tropical western Pacific. Detailed time series of planktonic foraminifer (G.ruber; white variety) d18O, d13C, and bulk CaCO3 mass accumulation rate (MAR) were generated, spanning the last 750 k.y. Sedimentation rates in this portion of the record average 8.5 cm/k.y., and vary from 4 to 16 cm/k.y.
Cross spectral analysis of the d18O and d13C time-series demonstrate that each contains increased variance at the primary orbital periodicities. The d18O record shows strong variability in the precessional-band and closely correlates with the SPECMAP d18O record and other high-resolution records. The dominance of a 23-k.y cycle in the d18O record agrees with other studies of the monsoon system in the Indian Ocean that have documented the importance of precessional insolation as a monsoon-forcing mechanism.
In addition, d13C is strongly coherent, with d18O at a period of 41 k.y (obliquity), suggesting a connection between surface water CO2 chemistry in the Sulu Sea and high- latitude climatic change. The d18O and d13C time-series both contain increased spectral variance at a period of 30 k.y. Although the source of 30-k.y. variability is unknown, other studies have documented late Pleistocene Pacific Oceanographic variability with a period of 30 k.y.
Major- and trace-metal analyses were performed on a second, less-detailed sample series to independently assess paleoproductivity changes and bottom-water conditions through time. Glacial periods are generally times of increased calcium carbonate and copper accumulation. The positive association between these independent indicators of paleoproductivity suggests an increase in productivity in the basin during most glacial episodes.
Changing bottom-water redox conditions were also assessed using the geochemical data. Low concentrations of molybdenum throughout the record demonstrate that bottom waters at this site were never anoxic during the last 750 k.y. The bioturbated character of the sediments agrees with this interpretation.
Project(s):
Ocean Drilling Program (ODP)
Coverage:
Latitude: 8.785600 * Longitude: 121.294200
Date/Time Start: 1988-12-14T15:00:00 * Date/Time End: 1988-12-15T07:00:00
Event(s):
124-769A * Latitude: 8.785600 * Longitude: 121.294200 * Date/Time Start: 1988-12-14T15:00:00 * Date/Time End: 1988-12-15T07:00:00 * Elevation: -3656.0 m * Penetration: 65.4 m * Recovery: 68.48 m * Location: Sulu Sea * Campaign: Leg124 * Basis: Joides Resolution * Method/Device: Drilling/drill rig (DRILL) * Comment: 7 cores; 65.4 m cored; 0 m drilled; 104.7 % recovery
License:
Creative Commons Attribution 3.0 Unported (CC-BY-3.0)
Size:
3 datasets
Download Data
Datasets listed in this publication series
- Linsley, BK; von Breymann, MT (1991): (Table 1B) Accumulation rates of ODP Hole 124-769A. https://doi.org/10.1594/PANGAEA.762111
- Linsley, BK; von Breymann, MT (1991): (Table 2) Sediment geochemistry of ODP Hole 124-769A. https://doi.org/10.1594/PANGAEA.762112
- Linsley, BK; von Breymann, MT (1991): (Table 1A) Stable carbon and oxygen isotope ratios of planktonic foraminifera of ODP Hole 124-769A. https://doi.org/10.1594/PANGAEA.762110