ABSTRACT
East Ferghana is a district in eastern Turkestan beside the Chinese frontier and E. of Samarkand and Kokand. The great valley of Ferghana is bordered on three sides by low hills, the “Adyrs,” of Upper Cretaceous and Kainozoic rocks, with occasional bosses of Paleozoic. This valley is bounded to the S. by an Alpine range, the Kichik Alai, a branch of the Alai Range. The rocks of the area include a long succession ranging from the Middle Cambrian to the Middle Carboniferous and including Silurian and a full representation of the Devonian. The sea withdrew in the Upper Carboniferous, and continental sediments were then laid down and continued through the Permian and Trias to the Lower Jurassic. The country was again reached by the sea in the Cenomanian and the deposition of marine beds began then and lasted till the Oligocene. The last deposits belong to the Pleistocene and include abundant loess.
