86 EXPLORATIONS IN TURKESTAN.
MORAINES IN THE TERSMEI ALA-TAU.
When we reached the southwest shore of Issik Kul ( July 14), the snowy summits of the Terskei Ala-tau were seen to the south ; so we crossed the outer, lower ranges from the delta to the upper valley of the Ula-khol, and there at once
carne upon an interesting group of moraines.
The first moraines seen (M, fig. 43) were in a longitudinal valley at the
northern base of the Terskei Ala-tau, about 3 miles to the southeast of the head of the Ula-khol gorge in the outer range. They had been formed by a glacier or
Fig. 51.—A Young Moraine within the Old Moraine in the Chalai Range, looking north.
glaciers that descended northward from the Kashga and Tura side valleys, and stood at an altitude of somewhat over 7,000 feet. Their hills were delicately rounded ; the streams had eroded open-floored valleys across the morainic belt ; no undrained basins remained ; some hillocks were isolated, as if the valley-floor gravels had been aggraded around them. The materials of the moraine were, as a rule, unweathered, but we found in fresh-cut banks a few stones decomposed to a friable condition.
About 2 miles to the south, and at an estimated elevation of between 8,500 and 9,000 feet, another moraine was seen in the Kashga Valley. This was judged to be much younger, as seen in the distance, because the stream had cut only a narrow trench through it.