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ARTICLE IN PRESS

Quaternary Science Reviews 23 (2004) 1567–1598

Sea-level change along the Italian coast for the past 10,000 yr

Kurt Lambecka,*, Fabrizio Antoniolib, Anthony Purcella, Sergio Silenzic

a Research School of Earth Sciences, Australian National University, Canberra ACT 0200, Australia
b ENEA National Agency for New Technologies, Energy and Environment, Via Anguillarese 301, 00060 S. Maria di Galeria, Rome, Italy

c ICRAM, Central Institute for Marine Research, via Casalotti 300, 00166 Rome, Italy

Received 20 February 2003; accepted 13 February 2004

Abstract

Relative sea-level change along the Italian coast and adjacent seas—the combined result of eustasy, glacio-hydro-isostasy and
vertical tectonic motion—exhibits considerable spatial and temporal variability throughout the Holocene. The tectonic contribution
can be evaluated from the elevation of MIS 5.5 shoreline-markers that are well developed in many localities and the eustatic and
isostatic contributions can be predicted from models of ice sheets and earth rheology. Discrepancies between observed Holocene sea
levels and model predicted values provide the information for reﬁning the model parameters, including the tectonic rates of vertical
movement. Recent and new Holocene and MIS 5.5 information from 30 sites in Italy has been evaluated and compared with model
results to calibrate the predictive model. The resulting parameters for the earth rheology and for the eustatic (ice-volume equivalent)
sea-level function are consistent with results from regions outside of the Mediterranean and reﬂect global values. Using the
calibrated model parameters the relative sea-level change due to eustasy and the concomitant isostasy is predicted across the central
Mediterranean region. Holocene tectonic rates of vertical motion are also given for the Italian coastal zone. At most sites where the
MIS 5.5 shoreline occurs above or below its ‘tectonically stable’ position, the inferred rates of vertical crustal displacements are
consistent with the assumption that average rates for the past B125,000 years are comparable to the average Holocene rates, but at
some locations in eastern Sicily and southern Calabria the Holocene rates exceed the longer term average rates.
r 2004 Elsevier Ltd. All rights reserved.

1. Introduction relative to coeval sea level can be established. During the
last decade, considerable new information (some un-
Sea-level change along the Italian coast is the sum of published) has become available but much of this is for
eustatic, glacio-hydro-isostatic, and tectonic factors. the later stages of the last global deglaciation. Thus the
The ﬁrst is global and time-dependent while the latter emphasis of the present study is on the Holocene period.
two also vary with location. The glacio-hydro-isostatic This material can be used to calibrate the parameters
part exhibits a well-deﬁned pattern and is readily deﬁning the isostatic models if an independent assess-
predictable whereas the tectonic component exhibits a ment can be made of the tectonic rates of change. What
less regular pattern that is generally of shorter wave- we attempt to do in this paper is to evaluate the
length and also less predictable. Together, these components contributing to sea-level change subsequent
components result in a complex spatial and temporal to the last deglaciation, develop a predictive model for
pattern of relative sea-level change around the central the Late Pleistocene and Holocene changes in relative
Mediterranean coast-line, observations of which provide sea level for this part of the Mediterranean, and estimate
information on earth-rheology, on rates of vertical rates of vertical tectonic motions. An important ques-
tectonic movements, and on the global ice–ocean tion is whether the various contributing components can
balance during glacial cycles. be separated and whether valid predictive models for the
relative change between the ocean and land surfaces can
Pertinent observations of sea-level change around the be developed.
coast include the age–height relationship of geological
deposits and archaeological structures whose positions The glacio-hydro-isostatic formulation for sea-level
change resulting from the growth and decay of the large
*Corresponding author. +61-2-6125-5161; fax: +61-2-6125-5443. high-latitude ice sheets is well known and the broad
E-mail address: kurt.lambeck@anu.edu.au (K. Lambeck). pattern of change in the central Mediterranean has been

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