JURASSIC AND CRETACEOUS DEPOSITS OF THE ZHYLYOYSKY DISTRICT OF THE ATYRAU REGION OF THE REPUBLIC OF KAZAKHSTAN

Abstract

The article describes the Jurassic and Cretaceous deposits of the Koikara, Imankara mountains, the Aksha tract (Akchi) of the Zhylyoysky district of the Atyrau region of the Republic of Kazakhstan. The material for the work was observations and finds made in the spring of 2023 in the Zhylyoy district, near the Koikara and Imankara mountains. The area of the Koikara and Imankara mountains is one of the most interesting localities in the Atyrau region for the study of paleofauna and sedimentary deposits. Jurassic deposits are composed of clay sands with nodules of dense sandstone, clays with bright yellow ferruginous crusts. The Cretaceous deposits are composed of sands, chalk clays and marls. Remains of invertebrate fauna were found, such as cephalopods Belemnitella mucronata, bivalve mollusks Gryphea dilatata, the shell of the sea urchin Echinocorys sp., single corals-scleractinium Caryophyllum similotrochus.