ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

events have an immediate direct impact on the dunes, establish
antecedent conditions for subsequent storms, and
usually are influenced by the local beach and nearshore
morphology and by human modifications of the system.
Five sites within the state of New Jersey have been selected
to monitor the dune changes. Nine topographic surveys of
0.5 km long shoreline segments have been conducted
between October, 1994 and September, 1996. Computergenerated
terrain models of the study sites have been produced.
The initial survey models form a basis for determining
changes in dune form and dune volume. Repeated
post-storm surveys are used to relate volumetric changes to
storms of different magnitudes. In addition, the models facilitate
the analysis of alongshore variations in dune recession
resulting from the storms by the generation of crosssectional
profiles of the dune system at any desired interval.
The pre- and post-storm cross-sectional areas are compared
to determine the foredune changes and the alongshore
pattern of erosion and accretion.
An examination of three of the study sites provides a comparison
between a natural control site and two examples of
developed sites. One comparison involves a measurement
of cross-sectional foredune area, derived from transects
spaced at 15m intervals, to characterize alongshore and intersite
variation. Between October 1994 and September
1996, the cross-sectional area data show a variation of net
change from _8m 2 to +9 rn' within the natural area, and
from -10 m' to +16 m' and from -8 m' to +4 rn' within the
developed areas The cross-sectional data set also records
the effects of a 5-year recurrence interval storm in January,
1996. In the natural site, the storm-related dune change varied
between -12 m' and +7 m', Within one developed site,
the change in cross-sectional area varied from -15 m' to
+5 m', whereas in the other developed site the variation
was from -12 m' to +3 m",
The study demonstrates that with single events, there are
areas of dune accretion as well as erosion within short segments
of the shoreline. These variations establish antecedent
conditions for future modification of the dune system.
In the developed areas, some of the alongshore variation
of dune change associated with the high frequency
storm events is related to beach structures and human manipulation
of the dunes.
PIER PAOLO PUTZOLU
Morphotectonic features of the high Garfagnana
and south-eastern Lunigiana (Nothern Appenines)
with the contribution of quantitative geomorphic analysis
Dipartimento di Scienze della Terra, Universita di Pisa,
via S. Maria 53,56126 Pisa, Italy
The two graben of the Lunigiana and Garfagnana represent
a sector of the northern Appenines which is of particular
sismogenetic interest and the study area corresponds
to the tectonics displacement that separates the two depressions.
The geological-structural picture is characterized
by a complex exstensional structure of post-Miocene
deformation which affects pre-existing compressive structure
of the fold-thrust belt. Outcrops of many formations
belonging to four different tectonic units (