Segmentation of the Apenninic Margin of the Tyrrhenian Back‐Arc Basin Forced by the Subduction of an Inherited Transform System

Abstract

In tectonics, the term "inheritance" includes previous structural, stratigraphic, and igneous features that are rheologically different from the surrounding rocks and/or that steer the lateral juxtaposition of different rheological domains. Inherited structures are ubiquitous in the continental lithosphere and under the effect of a given tectonic regime they can promote the development of structures differing from those that would develop in an ideal layer cake-like/cylindrical geological framework. The notion of inheritance has its roots in the Wilson's cycle, specifically in the concept of reuse of lithospheric-scale structures formed during previous rifting or collisional events (e.g., Dewey & Bird, 1970;Wilson, 1966). Since the 1980s, the systematic documentation of faults reactivated with an opposite sense of slip has shaped the idea of structural inheritance (e.g., Butler et al., 2006 and references therein), embraced by the concept of inversion tectonics (e.g.

Timing, Thrusting Mode, and Negative Inversion Along the Circeo Thrust, Apennines, Italy: How the Accretion‐To‐Extension Transition Operated During Slab Rollback

“…Two public seismic lines (Figures 2c and 3; http://www.videpi.com/) were interpreted, limited to two key horizons and to only clearly evident faults, to avoid any over‐interpretation of structures considering the low quality of the seismic lines. The top Messinian ‐ base Pliocene boundary consists of evaporites and gypsum‐arenites and forms a marked reflectors in seismic lines (e.g., Conti et al., 2017; Tavani, Cardello, et al., 2021). The boundary between the Meso‐Cenozoic carbonates and the overlying syn‐orogenic siliciclastic deposits is also a well‐recognizable reflector, which in the case of the LT‐329‐86V onshore seismic line (Figure 3b) is further constrained by outcrops to the NE and by the Fogliano‐1 well.…”

“…For example, the Upper Miocene flysch unit exposed between the Formia plain and the Mt. Massico area is interfingered with an enigmatic fan delta conglomerate that includes mostly clasts of deep‐water carbonates, but also of granite (Tavani, Cardello, et al., 2021). Analogously, the age of the lower Miocene flysch unit exposed at the Circeo promontory has a large degree of uncertainty (Accordi, 1966) and the small size of this exposure does not allow to infer its depositional setting.…”

“…Parts of the Circeo basinal and slope succession were drilled in the Mara‐1, Michela‐1, Fogliano‐1, and Tre Cancelli deep wells (Figures 2a and 2b). Moreover, they occur as exotic blocks within the Upper Miocene‐Pliocene chaotic complex of the Volsci Range and as clasts in the Upper Miocene Villa Treglia conglomerate exposed in the Formia plain, 50 km to the east of the Circeo promontory (Tavani, Cardello, et al., 2021).…”

From Fossil to Active Hydrothermal Outflow in the Back‐Arc of the Central Apennines (Zannone Island, Italy)

“…Tavani et al. (2021) include the Pontian Archipelago in the Ponza‐Alife accommodation zone, which is interpreted as a pristine deep‐seated transform fault system located in the subducting plate and was inherited from an Early Jurassic rifting episode, which caused the lateral juxtaposition of different rift domains.…”

“…ZI is part of the Pontian Archipelago, which is located in the Tyrrhenian back-arc basin on the western margin of the central Italian continental shelf (Figure 1). Tavani et al (2021) include the Pontian Archipelago in the Ponza-Alife accommodation zone, which is interpreted as a pristine deep-seated transform fault system located in the subducting plate and was inherited from an Early Jurassic rifting episode, which caused the lateral juxtaposition of different rift domains.…”