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

• Main Authors: Berger, Wolfgang H, Bickert, Torsten, Schmidt, Heike, Wefer, Gerold, Yasuda, Memorie K
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1993
• Subjects: Drilling/drill rig; Leg130; Joides Resolution; Ocean Drilling Program ODP; Planktonic foraminifera
• Online Access: https://dx.doi.org/10.1594/pangaea.696439; https://doi.pangaea.de/10.1594/PANGAEA.696439

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 ... : 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 ...