Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2019 Jul 12;9:10125. doi: 10.1038/s41598-019-46253-1

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2019

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

PMC Copyright notice

Neodymium isotopic sections for different geologic time bins interpolated using natural neighbor interpolation (Table S1) and schematic late Paleogene southwest Pacific circulation showing the progressive development of a proto-ACC. (Top) The 38-36.5 Ma Nd isotopic section (left) reveals the extent and mixing of North and South Pacific deep waters (Fig. S2b)^16,26. At Site 1124 northbound flow of less radiogenic South Pacific deep waters is indicated by an arrow. Contourites in the GSB and BT are deposited by northbound bottom currents (centre). A westbound Antarctic Slope Current (ASC) existed north of Antarctica. At Site 1124, surface currents were influenced by the proto-East Australian Current (EAC)³⁶; while deep northbound currents transported southern sourced deep waters. Cross-section (right) shows the northbound flow of South Pacific deep water (SPDW). (Middle) Equatorial/sub-equatorial deep waters with more radiogenic Nd isotopic signature arrive south of 30° S (36-34 Ma) and indicated by an arrow. A proto-ACC started to develop across the STR (centre) causing entrainment and upwelling (U) of proto-equatorial Pacific deep water (Proto-EPW) and subsequent northbound Ekman transport (right). The submerged Chatham Rise deflected the proto-EPW towards east. (Bottom) The 34-33 Ma Nd isotopic section (left) is similar to the 36-34 Ma section. A stronger proto-ACC caused upwelling (centre) and pronounced entrainment of proto-EPW (right). Colour codes for the paleogeographic maps⁷⁶ in the middle column: black = land, dark grey = shelf, light grey = slope or submarine rise, white = deep ocean.