Regional Deformation and Offshore Crustal Local Faulting as Combined Processes to Explain Uplift Through Time Constrained by Investigating Differentially Uplifted Late Quaternary Paleoshorelines: The Foreland Hyblean Plateau, SE Sicily. Issue 12 (30th November 2020)

• Record Type: Journal Article
• Authors: Meschis, M.; Scicchitano, G.; Roberts, G. P.; Robertson, J.; Barreca, G.; Monaco, C.; Spampinato, C.; Sahy, D.; Antonioli, F.; Mildon, Z. K.; Scardino, G.
• Is Part Of: Tectonics. Volume 39:Issue 12(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-11-30
• Subjects: marine terraces -- uplift -- normal faulting -- viscous process -- corals -- synchronous correlation; Geology, Structural -- Periodicals; 551.8
• DOI: 10.1029/2020TC006187
• Languages: English
• ISSNs: 0278-7407

Abstract

Abstract: Quaternary uplift is well documented in SE Sicily, a region prone to damaging seismic events, such as the 1693 "Val di Noto" earthquake ( Mw 7.4), the largest seismic event reported within the Italian Earthquake Catalogue, whose seismogenic source is still debated and, consequently, the long‐term seismic hazard is poorly understood. However, the spatial variation in the timing and rates of uplift are still debated, so it is difficult to link the dominant tectonic process(es) responsible for the uplift and the location of seismogenic sources. To better constrain the uplift rate, we have refined the dating of Late Quaternary marine terraces, using a synchronous correlation approach, driven by both published and newly obtained numerical age controls ( 234 U/ 230 Th dating on corals). This has allowed recalculation of uplift rates along a N‐S oriented transect within the Hyblean Plateau (HP) foreland region. Consequently, we have mapped the geometry of paleoshorelines along a coastline‐parallel transect and hence the rates of uplift. The results suggest increasing uplift rate from south to north across the HP and that uplift rates have remained constant through the Late Quaternary. This spatially changing but temporally constant uplift places constraints on the proportion of uplift produced by regional geodynamic processes versus produced by local faults, such as an offshore east dipping active normal fault. We discuss these new findings in terms of the long‐term seismic hazard for one of the most seismically active regions in the Mediterranean Basin. Key Points: Differential uplift is mapped in the Hyblean Plateau (SE Sicily, Italy) by looking at raised paleoshorelines over the Late Quaternary Differential uplift in the Hyblean Plateau is caused by a combined process between offshore normal faulting and regional processes Deformation rates associated to the offshore normal fault (Western Fault) need to be refined, subtracting the regional processes signal