ABSTRACT

This chapter describes the geology of Georgia and the Georgian part of the Black Sea. It is based on geological maps and seismic interpretation, integrated with well data and outcrop studies. The geology of Georgia consists of two major thrust belts: the Greater Caucasus and the Achara-Trialet belt, separated by two foreland basins (Rioni and Kartli) with an intervening basement culmination, the Dziruli Massif. The Achara-Trialet belt comprises a thick Upper Cretaceous and Paleogene sequence that restores to a rift and postrift basin of probable Paleocene age, connecting to the Eastern Black Sea. The basin began to close by the Oligocene. Structures are detached at Aptian and Oligocene levels and are large and open. The Rioni Basin developed mainly during the Oligocene and the Miocene through loading by the Achara-Trialet belt folds. It dies out into the Eastern Black Sea as the foreland basin megasequence merges with the postrift fill of the latter. North of the Rioni Basin, the major thrust front is a large south-dipping monocline, in front of which there are extensive salients detached in Upper Jurassic evaporites. The Kartli Basin passes into the Kura Basin to the east, where the foreland basin is deformed by the Greater Caucasus south-vergent thrust structures.