NEW DATA ON THE STRUCTURE AND AGE OF OLISTOSTROMAL AND SAND-SILTY ROCK MASSES OF THE GORNY-ALTAI SERIES IN THE SOUTHEAST OF THE GORNY-ALTAIANUI-CHUYA ZONE

New data on the age, stratigraphy, and structural location of the Corn y Altai series in the southeast of the Corny Altai Anui-Chuya zone hav e been obtained. Here, in the zone of joint of the marginal facies of the Anui-Chuya fore-are trough and the Early Cambrian accretion prism of the Kurai zone, a coarse-elastic (olistostromal) rock mass known in literature as the Chibit Formation is located. Coarse clastics are lo calized among polymictic and quartz-feldspathic sandstones as well as siliceous shales and clayey and limestone shales and are overlaid by t hick sand-silty deposits (variegated unit) similar in composition and structure to the flysch of the Corny Altai series in the inner parts o f the Anui-Chuya zone. The lilac and red intercalates in the siliceous rocks from the Chibit Formation and variegated unit contain sponge sp icules. Among them, the taxons Cjulanciella asymmetrica Fedorov and Di sparella cf. fusiformis Fedorov have been found. The first species dat es from the Middle Cambrian and the second - from the Middle-Late Camb rian. The structural, stratigraphic, and paleontological investigation s carried out in the southeast of Corny Altai permit faunal dating of the olistostromal rock mass (Chibit Formation) from the end of the Mid dle Cambrian and of the sand-silty rock mass (variegated unit) - from the end of the Middle-Late Cambrian. These formations may be considere d the marginal part of the Anui-Chuya fore-are trough made up of the M iddle-Late Cambrian flysch of the Corny Altai series.