SEDIMENTI E FORME QUATERNARI NELL’ALTA VALLE DELL’ATERNO (L’AQUILA)

Abstract

The investigated area is located in the Aterno valley river, Abruzzi Apennines. The sector of Arischia is represented by a wide valley
with numerous outcrops of continental Quaternary deposits. In particular, in the area between S. Giovanni and the south western side
of Mt. Pettino, a complex succession of depositional and erosive events has been defined. These events have been summarised in an
allo-morphosequential scheme obtained by the integration of allostratigraphic units and morphosequential units, which have been put in chronological order. The latter units correspond to relict surfaces (due to erosion or accumulation), variously located at the summit of the reliefs or along the flanks of the valley, sculptured in both marine substrata and in the continental units.
In the surveyed area a total of 8 allo-morphosequential units have been defined through the integration of 19 morphosequential units
and 11 allostratigraphic units. The chronological data (magnetic polarity and radiocarbon data), available for 6 allostratigraphic units, as well as indications derived from of correlations with units of adjacent intermountain basins, allowed to make a hypothesis about a chronological framework (between the Pliocene and the Late Pleistocene) for some of the defined units.
The analysis of this succession led to defined a geological evolution represented by the progressive embedding of erosive and depositional landforms and lithosomes, representing the progressive deepening phases of the hydrographic network. This geological evolution has been conditioned by the activity, even recent, of two faults affecting the bottom of the south western slopes of Mt. Marine and Mt. Pettino, respectively.