Subduction initiation causes broad upper plate extension: The Late Cretaceous Iran example
LITHOS, vol.398, 2021 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 398
- Publication Date: 2021
- Doi Number: 10.1016/j.lithos.2021.106296
- Journal Name: LITHOS
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aquatic Science & Fisheries Abstracts (ASFA), Chemical Abstracts Core, Geobase, INSPEC, Pollution Abstracts
- Karadeniz Technical University Affiliated: No
Abstract
Subduction initiation (SI) requires the sinking of one plate beneath another and this exerts extensional stress on the overlying plate. How broad a region is affected by SI-related extension is unclear because most of the clearest SI examples- such as Izu-Bonin-Mariana arc- are deep under the ocean. A major SI event is recorded in the Late Cretaceous forearc ophiolites of Iran, related to the subduction of Neotethyan oceanic lithosphere beneath Eurasia. This caused extreme extension of the Iranian plate, up to similar to 1000 km away from the proto-trench and generated a series of back-arc oceanic basins, sedimentary basins, and core complexes and exhumed high-P rocks. The Late Cretaceous Iran example shows that SI can cause strong extension over a much wider region of the overriding plate than heretofore imagined and offers an accessible natural laboratory for studying SI processes. This understanding also provides an attractive new explanation for the origin of the South Caspian Sea.