THE KOPET DAGH. 
49 
THE SERANI VALLEY. 
The Serani Valley is worn down on the gray shales of a pinched and torn 
syncline, between the broad limestone anticline of the main range on the northeast 
and the torn or fanlted anticline of the Bnuzan range (8,922 feet) on the sonthwest. 
The shales are largely removed and the limestone flanks of the valley are shaqjly 
ravined near the exit gorge ; bnt a few miles to the northwest we saw the terraced 
remnants of a higher valle>- floor (fig. 27), estimated to be 600 or 800 feet over the 
present stream. It was noted that the limestone flanks of the mountains sloped by 
relati\-eh- gentle and somewhat graded decli\-ity to these terraces, and that the 
flanks descended b\- much steeper and more ragged walls to the floor of the new 
valley near the outlet gorge, where the terraces had been largely removed. 
When the high terraces of the 
Serani \'alley are considered in con- 
nection with the lower ones alread}' 
described at Firuza and at the 
mouth of the lower gorge, a differ- 
ential uplift of the region is sug- 
gested. Such an uplift of the Serani 
Valley with respect to the moinitain 
front would not be measured simply 
by the height of the \'alle}- terraces. 
Fig. 27. — Terraces in ihe Serani Valley, looking northwest. 
Under the supposition of ui)lift, the slope of 
the stream in the gorge must ha\-e been much more gradual when it connected the 
now dissected floors of the earlier Serani and Firuza valleys than it is to-da}- ; for the 
earlier valley floor must have approached maturity, as is shown by its greater width 
in the Firuza syncline and by the more nearh* graded slopes of the limestone 
mountains over the Serani terraces, while the present valley is relatively inunature, 
as is shown by its narrowness in the shales of the Firuza syncline and by its abru])t 
walls and its land-slides near Serani ; and it is well known that mature valleys in a 
mountainous district must have a much more gradual slope than immature valleys. 
It is therefore reasonable to estimate the inferred recent axial uplift of the range at 
1,000 feet at least; indeed, 2,000 feet does not seem to me an excessive measure. 
On following the Serani Valley to the southeast on the morning of June i, 
we soon passed two large landslides (see fig. 26). The second one was a good mile in 
length, with irregular mounds and hollows strewn with huge limestone blocks. 
The slides seemed to ha\e come from the main range and to have been precipitated 
by the revival of valley erosion, whereby the basset edges of the limestones on the 
torn slope of the anticline were undennined. Beyond the slides the valley floor 
was aggraded for a mile or more, and the stream was here lost in its own deposits. 
At about 6 miles from Serani the ^•alle\■ is obstructed by a broad spur of shale, 
which remains there because the stream has become engaged in the limestones on 
the flank of the main range, in which it has cut an impassable chasm. The trail 
climbed the shale spur, which we then recognized to be, like the terraces at the 
other end of the Serani Valley, a remnant of an old wide-open valley floor, 400 or 
500 feet above the present stream. The chasm by which the stream passes around 
the spur is therefore to be regarded as a result of a local wandering of the stream 
