GEOLOGY. 37 



decomposition of the slates, but principally, in all probability, a subaerial deposit, like the 

 loess. In some places this clay covering is thin, and on a sharp incline parts of it are often 

 carried away, so that some of the slopes have a rather rugged appearance. Looking north 

 from the pass, I saw what was evidently limestone on one of the hills ; it was probably the 

 same as the carboniferous limestone seen south-west of Sanju, but there was no possibility 

 of getting near the hill. In a north by east direction I saw red thin-bedded sandstones 

 capping one or two hills, the beds apparently dipping to north-east. This red rock was very 

 probably identical with the cretaceous red sandstone north-west of Sanju, thus remarkably 

 indicating that this portion of the hills is a continuation of the Kuenluen. 



From the pass to Chehil Gombaz the rocks are palaeozoic carbonaceous slates, very vari- 

 able in strike and dip. Near the pass the strike is indistinct : in the valley north of Chehil 

 Gombaz, it is nearly east and west, the beds being vertical and much contorted. 



March 26th, Pasrobdt (across the Torat pass}. The whole way nothing but the same 

 carbonaceous slates and shales, and partly sandstone, were seen. They were dipping at a very 

 high angle to north by east or north-east by east. In some places they were interbedded 

 with crystalline limestone, and with white quartzite, in strata of about 40 to 50 feet in 

 thickness. At the junction of the two streams, the Pasrobat and the Tongitar, and much 

 higher up, I noticed old diluvial gravel, in some places up to the thickness of 300 feet 

 the boulders mostly consisting of crystalline gneissic rock : some of the boulders are of 

 huge dimensions, and all are well-rounded. These boulder deposits must have been formed 

 by enormous rivers and large quantities of snow. The gneiss is either fine-grained, with 

 biotite mica, sometimes almost schistose, or it is porphyritic with rosy quartz, white felspar 

 and a greenish mica. There is little schorl to be observed in any of the pieces. 



March 27th, Tdrbdshi, about eight miles in a western direction. The carbonaceous slates 

 and sandstone continued for about a mile from camp, seeming, however, more micaceous. 

 Then they gradually changed into dark carbonaceous mica schists with garnets ; this again 

 gradually into light-coloured mica schist, with more white quartz and less garnets, and this 

 after about two and a half miles from camp into gneiss. All the strata were dipping at about 

 50 to north-east and north-east by east. In many places gravels conceal the rocks to a 

 height of 150 feet above the river. On the greater heights dark-coloured schistose rocks are 

 seen ; they are mostly hornblendic. 



March 28th, Balghun. A march of about 20 miles across the Chichiklik plain and 

 the Kokmainak pass. All the rocks around are gneiss, which gets gradually schistose, but it 

 is cleaved in all directions and breaks up easily ; the irregular cleavage entirely obliterates the 

 bedding. 



March 29th and 30th, Balghun to Chushman, and thence to Tashkurgdn (SariJcol) . Two 

 marches of rather more than 20 miles altogether. The rocks are all metamorphic schists, rarely 

 micaceous, but chiefly chloritic, quartzose, and hornblendic. North-west of the camp the dip 

 is west by north ; previously it was east by south. On the western side of the valley are thick, 

 gravel deposits, the boulders mostly of gneiss and syenite. 



April 2nd, Kanshubar, 16 miles. The whole way nothing but gneiss, in different varia- 

 tions, was to be observed. At first where we entered the Tongitar (valley), the fine-grained 

 pale-whitish gneiss was interstratified with dark gneiss and syenitic gneiss, full of schorl ; 

 further on, syenitic gneiss prevailed, then bands of beautiful reddish gneiss occurred in it, 

 with reddish-brown quartz, reddish glassy felspar in large crystals, and bits of schorl. 

 Further on, the gneiss became more ordinary, both coarse and fine grained. 



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