Science Objectives for Trans-Arctic Coring Cruise

Cruise Report (5.25mb)

Use multibeam acoustics to find favorable sites for high sedimentation rates with targeted areas (Sites 1-9 on ship's track).

Obtain crossing lines of CHIRP seismic and sidescan sonar for core locations in order to determine core site setting.

Collect one multicore and one or two piston cores at each core site depending on recovery and local setting. Occasional box cores will be taken as needed.

Sample dirty sea ice when opportunity arises. This involves helicopter operations onto the ice and drilling or scraping the ice as required to get the sediment in the ice.

Tow seismic array behind the Healy to obtain as continuous a seismic profile across the central Arctic Ocean as possible in order to determine the origin of the ridges and other structures.

Specific questions involve:

The nature and origin of the Chukchi Borderland, which juts out into the Arctic Basin from the Chukchi Shelf.

The origin of the Mendeleev Ridge and its relationship to the Alpha Ridge, which appears to be a continuation of it.

How did the Amerasian Arctic open as an ocean?

To investigate the nature of the Gakkel Ridge where is morphology changes.

Icebreaker Oden