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ARTICLE IN PRESS

Quaternary Science Reviews 24 (2005) 1969–1988

Sea-level change in the Mediterranean Sea since the LGM: model
predictions for tectonically stable areas

Kurt Lambeck , Anthony Purcell

Research School of Earth Sciences, Australian National University, Canberra ACT 0200, Australia
Received17 March 2004; accepted 22 June 2004

Abstract

Sea-level change in the Mediterranean Sea during glacial cycles is determined by the temporally variable eustatic change and by
the spatially variable glacio-hydro-isostatic response of the earth and ocean to the growth and decay of ice sheets. Superimposed
upon this are the relative changes from any vertical tectonic movement of the land. For sites that are either tectonically stable or
where the magnitude of tectonic uplift is known, comparisons of observed change with predictions of the glacio-hydro-eustatic
signals provide constraints on the earth–ice parameters used. The resulting predictive models can then be used to interpolate sea-
level change andshoreline migration between the spatially and temporally limitedobservational data set. Whether such parameters
reﬂect the true properties of the mantle and ice sheets depends on whether an effective separation has been achieved from the
inversion of the observational data set. This paper explores this issue and demonstrates that observations from certain regions in the
Mediterranean are particularly important in effecting the separation. This is supported by a trial analysis of a small observation data
set from sites that exhibit some of the desirable features of an ideal data set. Basin-wide predictions of sea-level change, palaeo-water
depth and shoreline locations based on these analyses are presented for selected epochs.
r 2005 Elsevier Ltd. All rights reserved.

1. Introduction if the growth anddecay history of the continental ice is
known. In contrast, the changes wrought by tectonic
Sea level is deﬁned by the position of the sea surface processes, tendto be less predictable, of shorter
relative to the adjacent land and sea-level change is a wavelength and more episodic than the glacially-driven
measure of the relative shift in position of these two change. When combined, the two contributions result in
surfaces. A principal process contributing to sea-level a complex spatial andtemporal pattern of sea-level
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change on glacial time scales is the exchange of water change. On longer time scales, of order 410 years,
between the continental ice sheets andthe oceans, upon geological processes may become dominant in affecting
which may be superimposedvertical land movements sea level, such as plate-tectonic-driven modiﬁcation of
driven by active tectonic processes. The growth and ocean-basin geometry. On shorter time scales, of years
decay of the ice sheets change the ocean volume, deform and decades and for which it has been instrumentally
the ocean basins andtheir margins, and modify the monitored, oceanographic and climatic forcing (includ-
gravitational ﬁeld, or geoid, of the planet. All three ing thermal expansion) of the ocean surface may become
effects modify sea level. The deformational and gravita- important.
tional effects are spatially variable, functions largely of The Mediterranean basin has experienced major sea-
the distance from the ice sheets, but they are predictable level change during glacial cycles, evidence for which
occurs in both the geological andarchaeological
records, of decreasing resolution with time, throughout
Corresponding author. Tel.: +61 2 6125 5161;
fax: +61 2 6125 5443. the last glacial cycle. The analysis of this information
E-mail address: kurt.lambeck@anu.edu.au (K. Lambeck). from across the region can provide insights into the

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