Impact of Antarctic Circumpolar Current Development on Late Paleogene Ocean Structure

  title={Impact of Antarctic Circumpolar Current Development on Late Paleogene Ocean Structure},
  author={Miriam E. Katz and Benjamin S. Cramer and J. Robert Toggweiler and Gar Esmay and Chengjie Liu and Kenneth G. Miller and Yair Rosenthal and Bridget S. Wade and James D. Wright},
  pages={1076 - 1079}
The modern four-layered ocean structure developed during the early Oligocene, when Antarctica developed permanent ice cover. Global cooling and the development of continental-scale Antarctic glaciation occurred in the late middle Eocene to early Oligocene (~38 to 28 million years ago), accompanied by deep-ocean reorganization attributed to gradual Antarctic Circumpolar Current (ACC) development. Our benthic foraminiferal stable isotope comparisons show that a large δ13C offset developed between… Expand
Bipolar Atlantic deepwater circulation in the middle-late Eocene: Effects of Southern Ocean gateway openings
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Antarctic glaciation caused ocean circulation changes at the Eocene–Oligocene transition
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Sedimentological and oceanographic change in the Northwest Atlantic Ocean across the Eocene Oligocene Transition
The Eocene-Oligocene Transition (EOT) marks the most pivotal interval in Earth’s Cenozoic transition from warm, relatively ice-free ‘greenhouse’ conditions to a cooler ‘icehouse’ climate. The EOT sawExpand
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Changes in Pacific Ocean circulation following the Miocene onset of permanent Antarctic ice cover
We integrate micropaleontological and geochemical records (benthic stable isotopes, neodymium isotopes, benthic foraminiferal abundances and XRF-scanner derived elemental data) from well-datedExpand
Onset of Antarctic Circumpolar Current 30 million years ago as Tasmanian Gateway aligned with westerlies
Recon reconstructions of ocean circulation show that massive reorganization and homogenization of Southern Ocean water masses coincided with migration of the northern margin of the Tasmanian Gateway into the mid-latitude westerly wind band, which is reconstructed at 64° S, near to the northernmargin. Expand
Southern Ocean warming and Wilkes Land ice sheet retreat during the mid-Miocene
It is suggested that the mid-Miocene latitudinal temperature gradient across the Southern Ocean never resembled that of the present day and that the East Antarctic subglacial basins were highly sensitive to ocean warming. Expand


Late Oligocene initiation of the Antarctic Circumpolar Current: evidence from the South Pacific
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The Late Cenozoic closure of the seaway between the North andSouth American continents is thought to have caused extensive changes in ocean circulation and Northern Hemisphere climate. But the timingExpand
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[1] Neodymium (Nd) isotopes were measured on 181 samples of fossil fish teeth recovered from Oligocene to Miocene sections at Ocean Drilling Program Site 1090 (3700 m water depth) on Agulhas Ridge inExpand
Early Oligocene Onset of Deep-Water Production in the North Atlantic
The flow of deep-water masses is a key component of heat transport in the modern climate system, yet the role of deep-ocean heat transport during periods of extreme warmth is poorly understood. TheExpand
Cooling and ice growth across the Eocene-Oligocene transition
The Eocene-Oligocene (E-O) climate transition (ca. 34 Ma) marks a period of Antarctic ice growth and a major step from early Cenozoic greenhouse conditions toward today's glaciated climate state. TheExpand
Evidence for late Oligocene establishment of the Antarctic Circumpolar Current [rapid communication]
Removal of the last impediment to circum-Antarctic flow – opening of the Drake Passage between Antarctica and South America – is essential to establishment of the ACC, and has been placed in bothExpand
A scenario of Mesozoic-Cenozoic ocean circulation over the Blake Plateau and its environs
After the continental breakup of North America, Africa, and Europe, a sluggish, wind-driven circulation gyre probably formed in the juvenile North Atlantic basin. Surface flow in the western AtlanticExpand
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[1] Tectonic changes that produced a deep Tasmanian Gateway between Australia and Antarctica are widely invoked as the major mechanism for Antarctic cryosphere growth and Antarctic CircumpolarExpand
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[1] Benthic foraminiferal oxygen isotopic (d 18 O) and carbon isotopic (d 13 C) trends, constructed from compilations of data series from multiple ocean sites, provide one of the primary means ofExpand