Quaternary oxygen isotope record of planktonic foraminifera from ODP Site 805 on the Ontong Java Plateau

DOI

The oxygen isotope records of G. sacculifer and Pulleniatina in the uppermost three cores at Ocean Drilling Program Hole 805C span the last 1.6 m.y., an estimate based on Fourier stratigraphy. The last 700,000 yr are dominated by both eccentricity and obliquity-related orbital fluctuations. The range of variation of delta18O values is about 1.5‰, of which ca. 75% may be assigned to global ice-volume effect. The remainder of the range is shared by the effects of surface temperature variation, thermocline depth change (in the case of Pulleniatina, especially), and differential dissolution. Before 1 Ma, obliquity-related fluctuations dominate. The transition between obliquity- and eccentricity-dominated time occurs between ca. 1 and 0.7 Ma. It is marked by irregularities in phase relationships, the source of which is not clear. The age of the Brunhes/Matuyama boundary is determined as 794,000 yr by obliquity counting. However, an age of 830,000 yr also is compatible with the counts of both eccentricity and obliquity cycles. In the first case, Stage 19 (which contains the boundary) is coincident with the crest of the 19th obliquity cycle, setting the first crest downcore equal to zero, and counting backward (o19). In the second, Stage 19 coincides with o20.No evidence was found for fluctuations related to precession (23 and 19 k.y.) rising above the noise level, using plain Fourier expansion on the age model of the entire series. Detailed stratigraphic comparison with the Quaternary record of Hole 806B allows the recognition of major dissolution events (which increase the difference in delta18O values of G. sacculifer at the two sites). These occur at Stages 11-13, 16-17, and near 1.5 Ma (below o33).

Supplement to: Berger, Wolfgang H; Bickert, Torsten; Schmidt, Heike; Wefer, Gerold; Yasuda, Memorie K (1993): Quaternary oxygen isotope record of pelagic foraminifers: Site 805, Ontong Java Plateau. In: Berger, WH; Kroenke, LW; Mayer, LA; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 130, 363-379

Identifier
DOI https://doi.org/10.1594/PANGAEA.696439
Related Identifier https://doi.org/10.2973/odp.proc.sr.130.032.1993
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.696439
Provenance
Creator Berger, Wolfgang H; Bickert, Torsten ORCID logo; Schmidt, Heike; Wefer, Gerold ORCID logo; Yasuda, Memorie K
Publisher PANGAEA
Publication Year 1993
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (160.530 LON, 1.228 LAT); North Pacific Ocean
Temporal Coverage Begin 1990-02-13T19:00:00Z
Temporal Coverage End 1990-02-17T13:45:00Z