THE STRUCTURES OF THE ORE DISTRICTS,ORE FIELDS AND ORE DEPOSITS OF THE RUDNYY ALTAY

Polymetallic and pyritic-polymetallic ores of the Rudnyy Altay and its intersection with the Gornyy Altay are analyzed as to structure and classified as to ore districts, ore fields and ore deposits. In relating these categories to their containing structures, the author finds that ore districts are associated with long-developing tectonic zones, ore fields with second-order and thirdorder folds, chiefly in the marginal parts of anticlinoria, and ore deposits with shearing and tension fractures. Vein deposits are more common in fractured siliceous rocks. Lenticular and saddle-shaped deposits are commonly interbedded with pre-ore rocks. Concentrated ore complexes are particularly common in regions of block-folds or where synclinoria and anticlinoria intersect. Most of the Rudnyy Altay deposits are assigned to the late Hercynian.—A. Eustus.