Science

During the austral summer, 2007, approximately 20.5 km of high-quality seismic reflection data were collected in Granite Harbor.  The focus of this study was to find Quaternary geological successions in the hope that these records could help decipher environmental changes. The MacKay Sea Valley (MSV) is a deep trough thought to have been eroded beneath Granite Harbor by previous expansion of the MacKay Glacier. The seismic survey's intent was to image recent sediment layers that accumulated in the MSV following erosion.

The aim of the Offshore New Harbor Project is to obtain prima facies documentation of ice volume and climatic changes that occurred in the western Ross Sea during the Greenhouse World (55-34 million years ago, Ma) and across the transition into the Icehouse World (34-25 Ma). This research is crucial to our understanding of Antarctica’s role in past as well as future climate changes, since it was during this time interval (40-25 Ma) that atmospheric CO2 was as high as what is predicted for this century (see Pagani et al., 2005 in Science).

The Antarctic geological DRILLing (ANDRILL) Program is developing a new round of drill sites as part of the Coulman High (CH) Project in the western Ross Sea. The CH Project will target an early Miocene and Paleogene section to address themes on: evolution and stability of the cryosphere; warm climate periods in the Early Tertiary; orbital variability controls on climate; and tectonics within the West Antarctic Rift System. The drill sites are located east of Ross Island, on the Coulman High (~77.46 S; 171.23 – 171.68 E) at the former C-19 giant iceberg calving site. The CH site is located between the Victoria Land Basin and the Central Trough (Fig. 1), 125 km overland in a straight line NE from McMurdo Station. The water depth there is 834-871 m. Proposed drill sites are located on a seismic profile completed at the front of the Ross Ice Shelf ice shelf in 2003, that has since been covered by the advancing ice shelf that is moving north at ~740 m/year. The stratigraphic record here would extend the Miocene and younger data obtained from ANDRILL sites MIS and SMS and recover underlying sediments representing the Early Tertiary greenhouse world. Technical challenges include drilling into the seabed while the ice is moving north at more than 2 m per day and maintaining an open hole through the nearly 250 m-thick ice shelf. Drilling is anticipated to begin in the 2012-2013 season.

Science and operations for this project will be managed similar to previous ANDRILL successes at the MIS and SMS drill sites. The CH drill site has been successfully reviewed by the IODP site survey panel and an operations feasibility study has been completed. The U.S. proposal has been submitted for this project and is under review, and proposals for New Zealand and Europe are under development. ANDRILL is currently seeking the involvement of international partners in developing a multinational collaboration for this exciting new effort. For more information on how to participate in the Coulman High Project please contact the ANDRILL Science Management Office at ch@andrill.org.

The key aim of the SMS Project is to establish a robust history of past Antarctic ice sheet variation and climate evolution that can be integrated into continental and global records toward a better understanding of East Antarctica’s role in the past, present, and future global system. To achieve this aim, one ~1000 meter-deep drillcore will sample an inferred Miocene (0-17 million years ago) and younger sequence of seismic units that expand into the Victoria Land Basin. A new history of land vegetation and sea-ice cover will feed new data into glacial and climate models.

Co-Chief Scientists

Dr. David Harwood

Dr. Fabio Florindo

Keep track of the SMS project

The key aim of the MIS Project is to determine past ice shelf responses to climate forcing, including variability at a range of timescales. To achieve this aim ANDRILL will recover core from beneath the McMurdo Ice Shelf. The primary target for the MIS site is a 1200 meter-thick body of Plio-Pleistocene (0-5 million years ago) glacimarine, terrigenous, volcanic, and biogenic sediment that has accumulated in the Windless Bight region of a flexural moat basin surrounding Ross Island. A single ~1000 meter-deep drillcore will be recovered from approximately 900m of water.

Co-Chief Scientists

Dr. Tim Naish

Dr. Ross Powell

Keep track of the MIS project

The scientists from USA and New Zealand headed out in October of 2005 to find out just where to drill.

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Interested in how ANDRILL found where to drill and why? See how the science process takes place in today’s world.