76 WILLIAM T. M. FORBES 



farther west, and more directly north of Boghaz Koi, there is no 

 sign of the limestone or serpentine, but the Eocene ( ?) rocks which 

 extend west to Yaghly take their place. 



THE YUZGAD COMPLEX 



Five or six miles south of Boghaz Koi the serpentines and 

 limestones again make way for the rocks of Eocene facies, but now 

 they are much interrupted by igneous rocks in great variety. 

 Our road, the new chaussee, ran at first southeast, over the divide. 

 Then we entered the valley of a large stream which flows off to the 

 southwest and is followed by the old chaussee. We went upstream 

 (to the east) for a couple of miles along one of its tributaries, after 

 coming down from the divide along another; and then we turned 

 abruptly southeast to cross the very top of Kabak Tepe, the moun- 

 tain just north of Yuzgad, by a very complex system of zigzags. 

 From the height of land till we left the main valley to climb Kabak 

 Tepe, and actually till we were fairly up on the slopes of Kabak 

 Tepe, the supposed eocenes make up the mass of the rock. South- 

 west of the road about a mile south of the divide there could be 

 seen a flat mesa which has been used for "cliff -dwellings." It is 

 probably a tuff or soft trap like the beds so used elsewhere, and 

 made a distinctly incongruous note among the other rocks of the 

 district. In any case it is Neocene in date, and unconformable on 

 the local bedrock. Northeast of the road in the same neighbor- 

 hood there are several appearances of granite (probably more 

 nearly of the date of the bedrock). At the point of forking of the 

 old and new chaussees, where the road ceases to go south down 

 one tributary and turns east up the other, there are a couple of 

 trap dykes, both small, but perhaps outliers from more extensive 

 intrusions to the north. 



A couple of miles south of the valley of the tributary running 

 from east to west the supposed eocenes either disappear or else 

 change their character entirely under the influence of the many 

 igneous rocks, which now become dominant. Of this district one 

 can only say that it is a practically inextricable tangle. It is com- 

 posed, among other rocks, of granites, dark traps, schists, frag- 

 ments of Eocene beds (some containing fossils according to Tchi- 



