I00 EXPLORATIONS IN TURKESTAN.
After we had crossed the Kugart pass, in the Fergana range, and descended
into the valley of the (eastern) Kugart-su, another finely developed system of
highest terrace . 6 . Here and else-
terraces was found. The main and branch
valleys here, below the torrential headwaters, were eroded in a broad basin of tilted conglomerates that probably belong with the Narin formation. The spurs of the conglomerate hills rose above the
Fig. (fig. 7)
Fig. 66.—One-mile section of Gorge in the (western) Kugart where the hills and spurs were dissected
Valley, looking northeast. by rather close-spaced ravines, and the
slopes were beautifully graded. The terrace plain ascended with a rather strong gradient into the embayments between the spurs. In such a case it is evident that the material of the terrace was derived from the side valleys as well as from the
Fig. 67.—Upper Terrace of the (eastern) Kugart, near the Kirghiz Bridge, looking southwest. Dissected hills and spurs of tilted older conglomerates in the background.
main valley. The stream has intrenched itself 225 feet below the upper terrace plain at the Kirghiz bridge, carving several terrace benches in the process. The upper terrace plain and the stronger terrace benches continue for ro or 12 miles northward toward the Narin Valley. A mile upstream, south, from the rude Kirghiz bridge by which we crossed the river, a westward swing of its course