Identification:
Title:
Apparent cooling in the tropical Pacific during the Maastrichtian and diagenetic artifacts in Late Cretaceous stable isotopic trends in bulk carbonate from Ontong Java Plateau
Year:
2004
Source:
In: Fitton, J. Godfrey, Mahoney, John J., Wallace, Paul J., Antretter, Maria J., Banerjee, Neil R., Bergen, James A., Cairns, Graeme, Castillo, Paterno R., Chambers, Lynne M., Chazey, William J., III, Coffin, Millard F., Godard, Marguerite M., Hall, Stuart A., Honnorez, Jose, Ingle, Stephanie P., Kroenke, Loren W., MacLeod, Kenneth G., Naruse, Hajime, Neal, Clive R., Ogg, James G., Riisager, Peter, Sano, Takahashi, Sikora, Paul J., van der Werff, Wietze, White, Rosalind V., Zhao, Xixi, Proceedings of the Ocean Drilling Program; scientific results; basement drilling of the Ontong Java Plateau; covering Leg 192 of the cruises of the drilling vessel JOIDES Resolution; Apra Harbor, Guam, to Apra Harbor, Guam; Sites 1183-1187; 8 September-7 November 2000
Publisher:
Texas A&M University, Ocean Drilling Program, College Station, TX, United States
Volume:
192
Issue:
Pages:
Abstract:
Stable isotopic analyses of bulk carbonates recovered from Ontong Java Plateau during Ocean Drilling Program (ODP) Leg 192 (Holes 1183A and 1186A) show an approximately 0.5 increase in 18O values from the upper Campanian/lower Maastrichtian to the upper Maastrichtian. This shift is consistent with widespread evidence for cooling at this time. Similar shifts were found at other localities on Ontong Java Plateau (Deep Sea Drilling Project [DSDP] Sites 288 and 289 and ODP Site 807) and at DSDP Site 317 on Manihiki Plateau. These data extend evidence for Maastrichtian cooling into the southwestern tropical and subtropical Pacific. The record of apparent cooling survives despite a significant diagenetic overprint at all sites. Comparing average Maastrichtian 18O values among sites suggests that diagenesis caused 18O to first be shifted toward higher values and then back toward lower values as burial depth increased. Carbon isotopes at the six sites show no apparent primary shifts, but at four sites, the Cretaceous/Tertiary boundary interval coincides with a negative excursion attributed to alteration of sediments near the boundary.
Language:
English
Genre:
Serial
Rights:
URL: