40. STRONTIUM ISOTOPE STRATIGRAPHY OF THE OLIGOCENE-LOWER MIOCENE SECTION AT SITE 744, SOUTHERN INDIAN OCEAN1

• Main Authors: Enriqueta Barrera, John Barron, Alex Halliday
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Hess; Indian; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.576.8250; http://www-odp.tamu.edu/publications/119_SR/VOLUME/CHAPTERS/sr119_40.pdf

87Sr/86Sr ratios of well-preserved early Miocene-Oligocene planktonic foraminifers from Site 744 in the southern In-dian Ocean provide the highest southern latitude Sr isotope record of this age. The isotopic data have been calibrated with the site magnetostratigraphy. 87Sr/86Sr ages were also determined using the Sr isotope-age equations of Miller et al. (1988) and Hess et al. (1989). There is good agreement between the calculated ages from 87Sr/86Sr measurements using these equations and those derived from magnetobiostratigraphy. In addition, these equations were useful for inference of sediment ages in intervals where the paleomagnetic record is not well resolved and the biostratigraphy is inconclusive. The Site 744 87Sr/86Sr record can be used for correlation of Antarctic and low-latitude sequences and biostratigraphical zonation of foraminifers, radiolarians, diatoms, and calcareous nannofossils. This record will assist in the development of the high southern latitude biochronology.