This paper discusses a 5.2-0 Ma high-resolution terrigenous particle size record recovered from a sediment
drift off East Antarctica. The particle size properties of Hole 1165B are interpreted in the context of previously acquired
data on a continental shelf to slope transect drilled by ODP Leg 188 in Prydz Bay and the Cooperation Sea. The new
data indicate that the Lambert ice stream stayed predominantly landward of the shelf break in the early Pliocene (5.2-3.5
Ma) with periods of ice sheet recession on land. The middle Pliocene (3.5-3.1 Ma) is characterized as major ice
expansion during glacials with deposition of laminated clays from meltwater plumes on the continental rise, alternating
with periods of ice recession. A change in sedimentary facies and a decrease in sedimentation rates occurred at ~3.1 Ma
indicating a more retreated Lambert Glacier. Between 2.5 and 1 Ma the ice stream was generally stable and had become
cold-based with ice flow in a glacial trough extending to the shelf break. Three-four large pulses of coarse-grained
glacigenic debris mark the record at ~1 Ma. These are interpreted as extensive calving due to decoupling of the marine
terminus from its bed in response to Northern Hemisphere deglaciations and associated sea level rises.
