POTENTIAL FOR CORRELATION OF ANTARCTIC QUATERNARY MARINE GLACIAL-DEGLACIAL CLIMATE RECORDS, ORBITAL CYCLES, EUSTATIC CURVES AND MARINE ISOTOPE STAGES

A drillcore from Taylor Paleofjord, Victoria Land Basin, provides a multicyclic Quaternary stratigraphic record produced by trunk glacier advance-retreat, sea level oscillation, marine transgression-regression, and episodic sediment erosion and accumulation. This ice-proximal history is expressed as a stack of stratigraphic sequences (deglacial depositional episodes associated with tidewater glaciers, ice shelves, icebergs, ice-free marine waters) and inter-sequence unconformities (glacier grounding and erosional episodes). Sequences range between 8-22 m in thickness and are delineated by lithofacies characteristics, clast/matrix petrography, mineral provenance, and biostratigraphy. The same criteria are used to group 2 to 3 contiguous sequences into supersequence stacks of up to 45 m, also bounded by unconformities, but of probable greater duration than those between individual sequences. Extreme episodic sea level lowstands of ~120 m, coupled with advances by deep eroding glaciers during glacial episodes, created accommodation space for each supersequence and its sequences during subsequent similar elevations of sea level. Sequences filled this accommodation space during a series of minor sea level oscillations (~20-40 m) and less pronounced glacier advance-retreats. These data may support orbital eccentricity (~100 kyrs) and precession/tilt (~41/~23 kyrs) control of the Taylor Paleofjord sequence stack. It is unclear whether the primary mechanism for these episodic climate changes emanated from the Arctic or Antarctic cryospheres. If the Taylor Paleofjord succession was the result of orbital and eustatic factors, provision of more complete Quaternary records from the Victoria Land Basin promise eventual correlation with marine isotope stages. Prononced Quaternary glacial-deglacial dynamism at this margin of the East Antarctic ice Sheet and possibly the Ross Sea margin of the West Antarctic Ice Sheet is evident.