FINDINGS OF SMALL SHELLY FOSSILS IN LOWER PALEOZOIC DEPOSITS OF THE TALAS-ALA-TAN (NORTHERN TIEN-SHAN)

Recent paleontological data on the ancient deposits of the Talas Ala Tau contradicts accepted viewpoints on their stratigraphic subdivision. By using chemical preparation in a detailed stratigraphic study, small shelly fossils (chiolites, hyiolitelmints, and sponges) as well as algae were obtained from the flysch sequences (the Chatkaragai Subgroup) of the Karagai Group of the northern slopes of the Talas Ala Tau. According to these findings, the age of carbonates enclosed in the Urmaral Formation of the Chatkaragai Subgroup is considered to be the Early Paleozoic (the undivided Cambrian-Ordovician). Earlier, these sediments were attributed to the Upper Riphean.