Miocene strontium isotope record of DSDP Hole 30-289 ...

• Main Authors: Hodell, David A, Woodruff, Fay
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1994
• Subjects: Drilling/drill rig; Leg30; Glomar Challenger; Deep Sea Drilling Project DSDP; Planktonic foraminifera
• Online Access: https://dx.doi.org/10.1594/pangaea.729904; https://doi.pangaea.de/10.1594/PANGAEA.729904

A composite strontium isotopic seawater curve was constructed for the Miocene between 24 and 6 Ma by combining 87Sr/86Sr measurements of planktonic foraminifera from Deep Sea Drilling Project sites 289 and 588. Site 289, with its virtually continuous sedimentary record and high sedimentation rates (26 m/m.y.), was used for constructing the Oligocene to mid-Miocene part of the record, which included the calibration of 63 biostratigraphic datums to the Sr seawater curve using the timescale of Cande and Kent (1992 doi:10.1029/92JB01202). Across the Oligocene/Miocene boundary, a brief plateau occurred in the Sr seawater curve (87Sr/86Sr values averaged 0.70824) which is coincident with a carbon isotopic maximum (CM-O/M) from 24.3 to 22.6 Ma. During the early Miocene, the strontium isotopic curve was marked by a steep rise in 87Sr/86Sr that included a break in slope near 19 Ma. The rate of growth was about 60 ppm/m.y. between 22.5 and 19.0 Ma and increased to over 80 ppm/m.y. between 19.0 and 16 Ma. Beginning at ... : Supplement to: Hodell, David A; Woodruff, Fay (1994): Variations in the strontium isotopic ratio of seawater during the Miocene: Stratigraphic and geochemical implications. Paleoceanography, 9(3), 405-426 ...