The sedimentary sequences under the McMurdo Ice-Shelf provide geological data to reconstruct variations in transport and depositional mechanisms of terrigenous material due to variations in ice sheet extension, grounding line position, main ice-stream flows during glacial and interglacial periods.

Statistical analyses on detritital clay and heavy minerals, and quartz morphoscopy data have been performed on Pleistocene glacimarine sediments recovered during the ANDRILL-McMurdo Ice Shelf Project in Windless Bight (South of Ross Island) to investigate the relation between provenance, sedimentary processes and sediment composition.

Hierarchical cluster and discriminant function analyses on clays an heavy minerals reveal that a discontinuity in sediment characteristics exist at ca. 55 mbsf: stratified diamicton above 55 mbsf shows different composition  with respect to massive diamicton below this depth where sediments derived from the Transantarctic Mountain (TAM) source rocks  increase. Layers with different mineralogical characteristics occur throughout the core and they correspond to episodes of proximal glacimarine sedimentation and of proglacial and open marine sedimentation.

Hierarchical cluster and discriminant function analyses on quartz morphoscopy data confirm and detail the above interpretation. Quartz grains with a glacial origin prevail in the upper part of the core; grains with a marine and glacimarine origin prevail in the lower part of the core. Proximal glacimarine sediments and proglacial and open marine sediments have different quartz grain associations which reflect the prevailing sedimentary processes.

The mineralogical characteristics in Late Pleistocene MIS sediments reflect changes in ice provenance and in sedimentary processes. Sediments can derive from TAM and/or McMurdo Volcanic source rocks; moreover  subglacial versus sub-ice shelf and open marine processes influence the distribution of minerals and the surface quartz grain textures in the sediments.