Tectonics and Age Constraint Ridge subduction occurred well before the onset of glaciation in the southwest but not in the northeast. For the older glacial history, it is prudent to avoid the northeast area of the margin. The peninsula interior is 2000 m high and is composed largely of Andean-type plutonic and volcanic rocks. The topography and geology of the peninsula vary little along strike, which simplifies the models of erosional and depositional response to climate change. Snow accumulation governs the required rates of ice transport, hence basal sediment transport.
Greater accumulation means an expanded sediment record.
The Antarctic Peninsula is a narrow strip of interior upland, dissected by fjords and bordered by a broad continental shelf. The Antarctic Peninsula can probably provide a high-resolution record of glaciation back to perhaps 10 Ma. To go back further could involve entanglement with the tectonics of ridge-crest collision, making this a problem instead of an asset. However, because of the Antarctic Peninsula's more northerly position, its glacial history is shorter than East Antarctica's. The record before 10 Ma may be largely nonglacial, or it may reveal a stage of valley glaciation lacking regular ice-sheet extension to the continental shelf edge.