I-O EXPLORATIONS IN TURKESTAN. 
LONG CONTINUANCE OK PROCESSES OF DEPOSITION AND UPLIFT. 
In the precediii.a;' sections the varioiis rock formations and the Tertiar>' peneplain 
have been spoken of as though each of them represented a definite space of time 
rather than a stage of development. That the latter is the truer view is well 
shown by the phenomena along the borders of the Kashgar basin. South of the 
village of Artush, about 12 miles northeast of Kashgar, the Quaternary plain is 
broken by a ridge of interstratified silt and gravel which runs nearly east and west 
and rises 200 or 300 feet. It is an anticline so recently uplifted that its original 
form remains almost unchanged, although the material is soft and unlithified. The 
dip is gentle, about 6° on the north side and less on the south. The greater part 
of the strata which compose the anticline consists of buff silt, which is like loess 
in color and te-xture, although some portions at least are more clayey. It is 
apparently the same material as that which is now being deposited in the plaj-as of 
the surrounding plain. Interstratified with the silt are layers of stream gravel, 
showing old channels with cross-bedding and lateral unconfonnities. The top of 
the ridge is covered with gravel from 5 to 20 feet thick. West of Kashgar the silt 
continues, although with less of the character of loess. The vallej' followed by the 
caravan road to Osh leaves the plain through some low hills which seem to be a 
continuation of those already described near Artush. The)- consist of the same silts 
and graN'els, which dip greath- toward the plain and are well exposed in the steep 
sides of the valley. At the top lie several hundred feet of grave], then come numerous 
alternations of gravel and silt, \\ith a gradual increase in the thickness of the finer 
material, and at last ver}- thick yellow silts. The upper part of the latter are full of 
lenticular stream-channels, which grow broader and less numerous lower down. 
Although all the strata are verj* soft, they correspond in position to the fonnations 
whicli have been described above as the brown conglomerate and brown sandstone of 
the upper Tertiaiy, and by the rules of ordinary stratigraphy would be reckoned as of 
the same age. That they are younger is shown by their less degree of consolidation 
and by the fact that they can hardly be distinguished from the strata now in process 
of formation. Their folds, too, are younger than those of the sandstones, for although 
they rise above the level of the old peneplain, they are not beveled by it. Apparently, 
the Kashgar basin has long been growing smaller by a process of continuous folding 
along the edges, and as it has grown smaller the locus of deposition of the gravels 
which accumulate along its edges has gradually been pushed iu\\-ard. 
To make this more concrete, let us take the cross-section at Sugun Karaul, west 
of Shor Kul (fig. 124). In the Tian Shan plateau, 10 or 15 miles from the edge 
of the Quaternary plain of the Kashgar basin, the conglomerate at the top of the 
Tertiary- is highly folded and ver>- hard, but as the same stratum is traced southward 
and westward it becomes softer and less folded, until finally it seems to run into the 
soft gravel of verj' recent date which has been described in the preceding paragraph. 
Moreover, the old resistant conglomerate of the Tian Shan region has been smoothl\- 
baseleveled since its severe folding was completed, while the gentle folds of the soft 
young gravel have only been dissected by narrow valleys which have not yet pro- 
duced a maximum of relief This seems to mean that somewhere in Tertiarj' time 
