Structural setting of the Southern Apennine fold-and-thrust belt (Italy) at hypocentral depth: The Calore Valley case history

摘要: Abstract The reconstruction of the main structural features Southern Apennines (Italy), in correspondence with focal volume some strong earthquakes that have affected this chain, can be attempted by analysing reflection seismic lines and deep well logs comparison surface geology. For instance, Calore Valley its surroundings been object intense hydrocarbon exploration, a wealth subsurface data is available. Moreover, area was 1688 Sannio earthquake (macroseismic magnitude 7.1), new location has recently proposed for related causative fault system. present work defines setting Apennine chain location, compares it similar cases along Italian peninsula. analysis focussed on tectonic units (formed buried Apulia carbonate platform succession), which generally correspond to hypocentral depths axis Apennines. results show succession three thrusts, locally accompanied backthrusts. top relatively shallow: maximum depth does not exceed 1.8 s TWT (i.e. about 3500 m b.s.l.), while minimum occur ramp anticlines culminations, at ∼0.5 s 500 m b.s.l.). suggest underlying Paleozoic basement possibly involved thrusting. In regional perspective, extensional seismogenic structures seem share common characteristics. Indeed, they develop (i) an uplifted basement; (ii) rear set thrusts account shallow units; (iii) surface, proximity leading edge surficial unit formed succession. system fits these traits. light this, we finally speculate characteristics architecture could provide key major seismicity interpretative model identification possible areas gap part