Tectonic and climatic signals from apatite detrital fission track analysis of the Cape Roberts Project core records, South Victoria Land, Antarctica

• Published in: Tectonophysics
• Main Authors: Olivetti, V, Balestrieri, ML, Rossetti, F, Talarico, FM
• Other Authors: Balestrieri, Ml, Talarico, Fm
• Format: Article in Journal/Newspaper
• Language: English
• Published: ELSEVIER 2013
• Subjects: Detrital thermochronology; Climate/tectonics interaction; Cenozoic tectonic; Antarctica; Antarctic; Ross Sea; Victoria Land; McMurdo Sound; Cape Roberts; Young Peak; Antarc*; Ice Sheet
• Online Access: http://hdl.handle.net/11577/3329371; https://doi.org/10.1016/j.tecto.2013.03.017

The Cenozoic tectonic reorganization of the West Antarctic Rift System in the Ross Sea region occurred concurrently with a major change in the global climate system and a global reorganization of plate motions. This region thus provides the opportunity to study in detail a range of geological issues dealing with tectonic and climate feedbacks during the late Eocene/early Oligocene greenhouse/icehouse transition at high latitudes. With the aim to decipher tectonic vs. climatic forcing in the ice sheet drainage evolution, a detrital apatite fission track study was carried out throughout the Cenozoic drill-cored stratigraphic succession of the Cape Roberts Project (McMurdo Sound, Victoria Land Basin). Apatite fission-track ages of detrital samples, with de-positional ages between 34 Ma and 17 Ma, were decomposed into statistically significant age populations. Three age peaks were detected, reflecting different bedrock provenance areas: (i) a young peak (P1 between 34 Ma and 26 Ma) recording the signal of a source area exhumed with a constant denudation rate, but absent in the proximal continental area; and (ii) two peaks, older than 40 Ma, that are instead compatible with thermochronological data available from the onshore bedrock. P1 peak testifies a late Oligocene-early Miocene denudation event and traces a southern provenance of a fraction of the sediments filling the Cape Roberts Basin. We propose that this denudation event might have been triggered by renewed N-S transtensional shearing along the western shoulder of Victoria Land Basin, controlling glacial flow pattern and the associated sediment transport. (C) 2013 Elsevier B.V. All rights reserved.