Exposure of Carboniferous Granitoids on Triassic–Jurassic Seashores in the Western Caucasus: A Stratigraphical Review

Abstract

Granitoids are known to crop out on ancient seashores, but the related geological evidence remains limited. The information from the Western Caucasus sheds light on the stratigraphical distribution of coarse siliciclastic beds associated with late Carboniferous granitoids of the Dakh, Rafabgo, and Sakhray crystalline massifs. For the purposes of this study, the available information was reviewed and verified against the modern stratigraphical scales. It is established that the considered coarse sisliciclastic beds occur at five stratigraphical levels of the Triassic–Jurassic succession. A rocky seashore with granitoid exposures existed for a short time around the Sakhray and probably Rufabgo massifs at the very beginning of the Triassic. The Dakh Massif possessed such a shore twice (at least), i.e., in the Norian–Rhaetian and the Early Toarcian. However, it cannot be excluded that rocky shores persisted there for >50 Ma. Generally, the Western Caucasus provides an example of granitoid exposures on Mesozoic seashores and adds knowledge of the global distribution of rocky shores in the Triassic and Jurassic periods.

Keywords

• coarse siliciclastics
• Greater Caucasus
• Mesozoic
• rocky coast
• sea-level changes
• stratigraphical correlation