Constrain on the Kinematic Evolution of the Central Apennines (Italy) Using Paleomagnetic and Geological Data
Abstract
The Apennines describes two major first-order arcuate features: the Northern Apennines Arc and the Southern Apennines-Calabrian Arc. We compare and discuss these major arcs, which are characterized by several differences, mainly related to paleogeographic domains, stratigraphic successions, structural setting and geodynamic evolution. The two arcs join in the Central Apennines, which are bounded by two main ca. N- S structural features: the Olevano-Antrodoco and the Sangro-Volturno lines. We reconstruct a kinematic model related to the Tortonian-Quaternary evolution of the Central Apennines thrust system, by evidencing the differences in sign and magnitude of vertical-axis rotation introduced in the Northern and Southern Apennines during the Neogene orogenesis. In fact, the Northern Apennines Arc is characterized by counterclockwise (CCW) rotations in the northward sector, changing to clockwise (CW) toward the Central Apennines, and by amount of shortening up to approximately 15-20 km. Instead, minor salients in the Central Apennines show strong CW and CCW rotations confined near the apex and corresponding to maximum shortening of ca. 15 km (e.g., the Gran Sasso salient). Finally, the Southern Apennines-Calabrian Arc is characterized by CCW rotation in the Southern Apennines, changing to strong CW rotations in Sicily; the amount of shortening increase south-westward up to 80 km (e.g., the Matese- Frosolone salient). The different kind of paleomagnetic rotations documented in curved structure belonging to the Northern and Southern Apennines may be ascribed to both different driving mechanisms and paleogeographic-structural heritage. We thus propose to use the different style of paleomagnetic rotations in arcuate shapes as a tool to discriminate if structures located in the Central Apennines geologically belong to the Northern Apennines Arc or to the Southern Apennines-Calabrian Arc. Furthermore, the Sangro-Volturno line should not be interpreted as a major tectonic separation between the two major Arcs, but represent the oblique ramp of the Plio-Quaternary frontal thrust of the Central Apennines.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFMGP51A0734C
- Keywords:
-
- 1525 Paleomagnetism applied to tectonics: regional;
- global;
- 1527 Paleomagnetism applied to geologic processes;
- 8015 Local crustal structure;
- 8038 Regional crustal structure