Middle Miocene events in ODP and DSDP sites of the Ross Sea, supplement to: Bart, Philip J (2003): Were West Antarctic Ice Sheet grounding events in the Ross Sea a consequence of East Antarctic Ice Sheet expansion during the middle Miocene? Earth and Planetary Science Letters, 216(1-2), 93-107

• Main Author: Bart, Philip J
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2003
• Subjects: Drilling/drill rig; Composite Core; Leg28; Leg120; Glomar Challenger; Joides Resolution; Deep Sea Drilling Project DSDP; Antarctic; East Antarctic Ice Sheet; Ross Sea; Transantarctic Mountains; West Antarctic Ice Sheet; West Antarctica; Antarc*; Antarctica; Ice Sheet
• Online Access: https://dx.doi.org/10.1594/pangaea.722496; https://doi.pangaea.de/10.1594/PANGAEA.722496

Seismic correlation of glacial unconformities from the Ross Sea outer continental shelf to chronostratigraphic control at DSDP sites 272 and 273 indicates that at least two West Antarctic Ice Sheet (WAIS) expansions occurred during the early part of the middle Miocene (i.e. well before completion of continental-scale expansion of the East Antarctic Ice Sheet (EAIS) inferred from delta18O and eustatic shifts). Therefore, if the volume of the EAIS was indeed relatively low, and if the Ross Sea age model is valid, then these WAIS expansions/contractions were not a direct consequence of EAIS expansion over the Transantarctic Mountains onto West Antarctica. An in-situ development of the WAIS during the middle Miocene suggests that either West Antarctic land elevations were above sea level and/or that air and water temperatures were sufficiently cold to support a marine-based ice sheet. Additional chronostratigraphic and lithologic data are needed from Antarctic margins to test these speculations.