EXPLORATIONS IN TURKESTAN.
lines are much less developed than are those of our Quaternary Lakes Bonneville and Lahontan in Utah and Nevada, or of our Laurentian Glacial Great Lakes in New York and farther west. The Caspian shorelines are, however, easily recognized at many points on the hillsides about Baku, where they are marked by horizontal benches of cobbles, gravel, and shells, more or less cemented, at various levels up to 300 or 500 feet (fig. i6). Sjögren says that the last rise of the Caspian left marls and clays 5o or 55 meters over the present water level. On the most exposed headland that we visited, about 6 miles northeast of Baku and i 6o feet above the sea, blocks of sandstone, 5 or ro feet in size, were detached from their ledges and left standing in disorderly attitudes, which seemed less the-result of ordinary pro-
Fig. 16.—An old Caspian Shoreline, near Baku.
cesses of weathering than of former seashore forces. There are also occasional mounds or delta-like deposits of fine silt in protected re-entrants of former shorelines as at A, fig. 15, at altitudes similar to those of the cobble benches ; but these features are so discontinuous that it was not possible to correlate them safely. Their discontinuity does not appear to be due to subsequent erosion, for none of the shore records seem to have suffered significant change, except one of the silt deposits that lies in a ravine, and that has been channeled by its wet-weather stream. This silt deposit (A', fig. 15) is just west of Bibi-Eibat and contains land shells in its upper part, but its form and position are such as to indicate the deposition of its greater volume as a delta. It lies on a bed of well-rounded cobbles and bowlders, exposed
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