Neogene West Pacific tectonic influence on global climate via the Kuroshio Current

Lead Research Organisation: University of Cambridge
Department Name: Earth Sciences


The proposed research would produce a thorough quantitative foraminiferal study of 500 deep-sea sediments samples and aims to reconstruct the paleoceanographic changes in the West Pacific Ocean in the vicinity of the Kuroshio Current. The study is based primarily on coarse fraction (>150 micron) microscopic examinations. However, the micropaleontological work on planktonic and benthic foraminifera assemblages will be complemented by the analysis of stable isotopes (O18 & C13 ratios) measured on foraminifera extracted from selected samples. These analyses should confirm the stratigraphy of Site IBM-3C as well as inform the paleoceanographic and paleoclimatic interpretations obtained for the samples.

At such a subtropical location (30deg N), the study of the planktonic assemblages is a very useful contribution for reconstructing changing surface conditions because glacial and interglacial faunal assemblages are very contrasted. In particular, the study will provide needed data about changes in the Kuroshio Current path, which are potentially linked to changing ENSO intensity in the Pacific Ocean. The study focuses on the last 6 Ma.

In the area of the IBM and at 2114 water depth, the low resolution study of the benthic foraminifera assemblages extracted from 50 coarse fraction samples will provide some estimates of paleo-depth and deep-water environmental changes at a time resolution better than 1 Ma throughout the Neogene.

All analyses will be performed in the Godwin Laboratory for Paleoclimate Research (Earth Sciences Department, Cambridge University) from carefully selected Neogene sediments taken on board JOIDES Resolution during Leg 350 by Dr. Vautravers sailing as a foraminifera expert.

Planned Impact

Sampling, documenting and comparing a large range of parameters from as many places as possible using a variety of tools and research techniques and the skills of a number of people is of paramount importance to making progress into Earth Sciences. This scientific endeavor slowly builds and improves the understanding of the Earth's present and past environments and the processes involved. Such systematic and integrated work remains central to IODP 45 years after its creation. Taking this broad view, Dr. Vautravers work is a small piece of a very large puzzle and is likely to contribute in ways, which I cannot be fully anticipate before carrying the actual work and interpreting the new data.

However, the main impact of this research will likely be on the paleoclimatic research community. They will benefit from the acquisition of a new and original data-set in a sensitive, important and yet relatively under-documented part of the climate system which is the area affected by the Kuroshio Current South of Japan.

Furthermore, the expected results of this research may be of interest to climate modelers, interested in the impact of ENSO and major western boundary currents on rapid climate changes. And they could also be of relevance to paleoclimate modelers concerned in the interaction between the slow evolution of the Earth's crust and the Earth climate.

The development and improvement of climate models has a clear relevance to understanding current and anticipated climatic changes.

Most of the impact on the general public will be achieved via Dr. Vautravers web profile and personal page exposing the aim and the progress of her research but also via the creation of a concise online resource on microfossils, some teaching documents/tutorial and the development of education and outreach activities in liaison with other members of the Earth Sciences Department.
Description This proposal provided salary support Dr. Maryline Vautravers to participate in IODP Expedition 350 (Izu-Bonin-Mariana Rear Arc) from 30 March to 30 May 2014. Ongoing work includes oxygen isotope analysis of foraminifera to deterime the stratigraphy and age of two sites recovered.
Exploitation Route ongoing
Sectors Environment

Description Data collection and interpretation are ongoing.
Sector Environment