The Yablonovi and Stanovoi Ranges in the Light of New Data

MOST relief maps of Siberia show a sinuous divide, marked Stanovoi or Yablonovi Mountains, separating the Arctic and Pacific drainage basins from Mongolia to the Bering Sea. Recent explorations have proved that the two ranges are independent, both orographically and structurally. The name Yablonovi, which was first applied by the Cossack invaders in the seventeenth century to the Baikal-Nerchinsk watershed, comes from a Buriat name for the pass between the Khilok and Chita valleys-Yablenny Daba. Gmelin derives it from a word for boulders, while Fisher suggests a connection with the Russian word yabloni (apple trees); it was this latter derivation which led Georgi to call the range the Apfelgebirge. Unfortunately however no apples are known in the district, and the detritus is all angular. The name Stanovoi (prominent) is also due to the Cossacks and was first used in the Aldan sector, where the range conspicuously overtops the others. Later its use was extended to the entire divide, the term being linked with Yablonovi to designate the whole area between the Nercha river system up to the Kolima and Anadir region. (See folding map at the end of the Journal.) Leaving out all former descriptions of this watershed, which are scanty and often incorrect, we must mention that it was the geologist Middendorf who first saw the Stanovoi-Yablonovi range on his journey in this region. He already distinguished the two ranges, and traced the Yablonovi N.E. as far as the upper parts of tributaries of Lake Baikal. He considered the Stanovoi range to be its continuation to the upper course of the Selemdja and Bureya rivers, stating also that it was a mistake to use these two denominations for the whole distance of the watershed between the oceans. He divided the Stanovoi range into two parts-the western or Olekminski, and the eastern, or Zeiski ranges. Middendorf, according to Erman, called the continuation of the Stanovoi range along the coast of the Okhotsk Sea the Aldanski range. In 1875, on the basis of the existing hypsometrical data, Kropotkin, in his orographical map of Eastern Siberia, traced the Yablonovi range in the shape of a ledge between the higher and lower plateaux in a straight line from S.W. to N.E., beginning from Mongolia, past Urga and Chita across the Olekma river at its turning northward and up to the Timptom river. That part of the Stanovoi range which is on the western coast of the Okhotsk Sea he considered to be the immediate continuation of the Great Khingan which he traced in the shape of a ledge between the lower plateau and the southeastern elevations, from Mongolia across the Amur river, along the Zeya river system as far as the Uda river. The other part of the Stanovoi range he traced as an insignificant watershed between the Aldan river system and the upper Zeya and Uda on the lower plateau. Thus he altogether separated the Yablonovi range from the Stanovoi. Thirty years later, in an English paper on the orography of Asia, he reproduced the same map with slight alterations;