13. Data Report: Oxygen and Carbon Stable Isotope Records of the Miocene Calcareous Microfossils from ODP Leg 189 Sites 1170 (South Tasman Rise) and 1172 (East Tasman Plateau)1

Atsuhito Ennyu2, 3 and Michael A. Arthur2


Downcore oxygen and carbon stable isotope records of planktonic and benthic foraminifers and fine-fraction carbonate from the southern high latitudes provide critical paleohydrographic constraints on the evolution of the Southern Ocean climate. In particular, the potential effects of an intensified Antarctic Circumpolar Current on the thermal isolation and cooling of the southern high latitudes, production of cold deep waters, and, ultimately, accumulation of continental ice on Antarctica in the middle Miocene are matters of interest. Using sediment materials from Ocean Drilling Program Leg 189 Sites 1170 and 1172 off Tasmania, Ennyu and Arthur [N1] established the surface- and deepwater stable isotope records in the Southern Ocean across the middle Miocene event of the east Antarctic ice sheet expansion and discussed the paleoclimate proxy records in terms of the thermal evolution of the southern high latitudes and its effect on deepwater circulation.

This report provides data tables and other supporting information relevant to discussions presented in Ennyu and Arthur [N1]. Items included in this report are (1) the oxygen and carbon stable isotope data measured on the Miocene bulk fine-fraction (i.e., <63 Ám, primarily polyspecific nannofossil assemblage) carbonate and planktonic and benthic foraminifers from Holes 1170A and 1172A and (2) the Miocene depth-age models for the two sites.

1Ennyu, A., and Arthur, M.A., 2004. Data report: Oxygen and carbon stable isotope records of the Miocene calcareous microfossils from ODP Leg 189 Sites 1170 (South Tasman Rise) and 1172 (East Tasman Plateau). In Exon, N.F., Kennett, J.P., and Malone, M.J. (Eds.), Proc. ODP, Sci. Results, 189 [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/publications/189_SR/112/112.htm>. [Cited YYYY-MM-DD]

2Department of Geosciences, The Pennsylvania State University, University Park PA 16802, USA.

3Present address: Division of Earth and Planetary Sciences, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan. aennyu@nature.sci.hokudai.ac.jp

Initial receipt: 12 March 2003
Acceptance: 4 February 2004
Web publication: 14 April 2004
Ms 189SR-112