Prydz Channel Fan and the History of Extreme Ice Advances in Prydz Bay

Brief description

During the late Neogene, the Lambert Glacier-Amery Ice Shelf drainage system flowed across Prydz Bay in an ice stream that reached the shelf edge and built a trough mouth fan on the upper continental slope. The adjacent banks saw mostly subglacial till deposition beneath slower-moving ice. The fan consists mostly of debris flow deposits derived from the melting out of subglacial debris at the grounding line at the continental shelf edge. Thick debris flow intervals are separated by thin mudstone horizons deposited when the ice had retreated from the shelf edge. Age control in ODP Site 1167 indicates that the bulk of the trough mouth fan was deposited prior to the Brunhes-Matuyama Boundary (780 ka) with as few as 3 debris flow intervals deposited since then. This stratigraphy indicates that extreme advances of the Lambert Glacier-Amery Ice Shelf system ceased during the mid Pleistocene. Possible causes for this change are progressive over-deepening of the inner shelf, a reduction in maximum ice volumes in the interior of the East Antarctic Ice Sheet caused by temperature change and a change in the interaction of Milanckovich cycles and the response time of the ice sheet.\n\nYou can also purchase hard copies of Geoscience Australia data and other products at http://www.ga.gov.au/products-services/how-to-order-products/sales-centre.html

Full description

View the online article in Scientific Results, Vol. 188, - View the online article in Scientific Results, Vol. 188,