Morphological and morphometric approach to the study of the structural arrangement of northeastern Abruzzo (central Italy)

The morphotectonic research at the Dipartimento di Scienze della Terra of the Universita di Roma ''La Sapienza'' aims to define the role of tectonics and neotectonics in the morphological evolution of central Italy. In this context the relationships between morphology and tectonics have been investigated in an area of northern Abruzzo extending from the Apennine chain to the Adriatic Sea. Morphological and morphometric analyses carried out show that the geomorphological evolution of the study area was strongly affected by tectonics, especially recently. The most recent extensional tectonics intersect the previous compressive structures (overthrust, reverse faults, folds, strike-slip faults) determining the structural arrangement characterized by uplifted and downthrown blocks. Morphological analysis shows that extentional tectonics occurred with the following alignments: NW-SE, NNW-SSE, NE-SW, ENE-WSW, N-S and E-W. The spatial variability of amplitude of relief values corroborated the observations obtained from previous analyses; in particular the existence of different blocks, differentially uplifted along the alignments mentioned above. Finally, data obtained through the statistical analysis of preferred stream orientations confirm the previous considerations, showing that the same tectonic directions markedly influenced the drainage network development. Streams of lower order preferentially follow the N-S and E-W directions which suggests that these tectonic trends were active until very recent times (at least up to the Late Pleistocene). The results obtained testify both to the effectiveness of the methodological approach and the likelihood of the proposed morphotectonic arrangement of the study area.