OASES. 321 
Asa center of trade old Anau lay at the intersection of two important routes, 
the route from Meshed to Khiva crossing here with the great through way from 
Balkh via Merv round the Caspian’s southern shore. 
THE BUILDING OF A TILTING DELTA. 
The Anau delta is one of a group of similar fan-like plains spread out, side by 
side, from the mountains, and merging together into a piedmont whose slope 
averages perhaps 1 in 100. Although the history of such an area is essentially 
one of a varied aggradation, there is a peculiar deviation from this rule towards 
the margins of a Central-Asian plain, a deviation which has especially complicated 
the part which of anv delta, subaerial or subaqueous, is necessarily most complex 
in manner of growth. It is only well out on the area of deposition that only 
! 
ee aes Imiere = 
olga eae ! 
200ft. 
Djillan Ooti Y 

(A) 






Terrace 
Z fer LU TLLLLILLILIEL 
© SEALE = a Settled | ayers ei clay 
= Ss 
(B) 



Hh Valy 
4 Py) / 
Yi 
/, VIHA 
7™ Loess 
Alluvial gravels 

(Cc) 
Fig. 485.—River-cut Mounds of Millitinskaya (Timur’s Gate). 
deposition takes place, for most of the layers formed near the apex of radiation 
afterwards suffer removal to a greater distance. No permanent growth of the 
apex itself can take place without either a corresponding aggradation of its 
debouching valley’s flood-plain above, or a relative sinking of the plain below. Of 
such a sinking we have manifold evidence, and it is the way in which the plains 
of Central Asia sank that wrought their marginal peculiarities. This of course 
is the uptilting of narrow strips of piedmont beds forming low ridges with fault- 
scarps facing mountainwards and back of which the strata and conformable surface 
slope into the basin where they are buried by later waste. Whatever the cause of 
sinking, these uptilted piedmonts have resulted; and, with that part of the Anau 
delta where the oases were, tilting appears to have been one of the controlling 
factors of topography, not only of the present surface but also, as we shall see, 
of the surface of antiquity now buried by later waste. 
