24 



SECOND YARKAND MISSION. 



PART IV. 



GEOLOGICAL OBSERVATIONS MADE ON A VISIT TO THE CHADYR-KUL, THIAN SHAN RANGE. 



[From Records of the Geological Surrey of India, Vol. VII, p. 18 ; and Quart. Jour. Geol. Soc., 1874, Vol. XXX, p. 174.] 



AFTER, a stay of nearly a month in our embassy quarters at Yangishahr, near Kashghar, 

 the diplomacy of our envoy secured us the Amir's permission for a trip to the Chadyr-kul, a 

 lake situated close on the Russian frontier, about 112 miles north by west of Kashghar, 

 among the southern branches of the Thian Shan range. Under the leadership of Colonel 

 Gordon, we Captain Trotter and myself left Yangishahr about noon on the last day of 

 1873, receiving the greeting of the new year in one of the villages of the Artysh valley, 

 some 35 miles north-west from our last quarters. On the 1st of January 1874 we marched 

 up the Toyanda river for about 20 miles to a small encampment of the Kirghiz, called Chung- 

 terek ; and following the Toyanda, and passing the forts Mirza-terek and Chakmak, we camped 

 on the fifth day at Turgat-bela, about 11 miles south of the Turgat pass, beyond which, 

 5 miles further on, lies the Chadyr-kul. On the sixth we visited the lake, and on the day 

 following retraced our steps, by the same route we came, towards Kashghar, which we reached 

 on the llth January. 



Having had a day's shooting at Turgat-bela, and one day's halt with the King's 

 obliging officers at the Chakmak fort, we were actually only nine days on the march, during 

 which we accomplished a distance of about 224 miles. It will be readily understood that, 

 while thus marching, there was not much time to search for favourable sections in out-of-the- 

 way places, but merely to note what was at hand on the road. I can therefore only intro- 

 duce my geological observations as passing remarks. 



Leaving the extensive loess deposits of the valley of the Kashghar Daria, the plain rises 

 very gradually towards a low ridge, of which I shall speak as the Artysh range. It is remark- 

 ably uniform in its elevation, averaging about 400 feet, somewhat increasing in height towards 

 the west and diminishing towards the east, which direction is its general strike. This range 

 separates the Kashghar plain from the valley of the Artysh river, which cuts through the 

 ridge about 8 miles nearly due north of the city. Viewed from this, the entire ridge 

 appears very regularly furrowed and weather- worn on its slope, indicating the softness of the 

 material of which it is composed. One would, however, hardly have fancied that it merely 

 consists of bedded clay and sand, mostly yellowish white, occasionally reddish, and some- 

 times with interstratified layers of greater consistency, hardened by a calcareous or silicious 

 cement. On the left bank, in the passage of the river through the ridge, the beds appear in 

 dome shape, gently dipping towards the Kashghar plain on one side, and with a considerably 

 higher angle into the Artysh valley on the other. On the right bank at the gap all the 

 exposed beds dip southward, those on the reverse of the anticlinal having been washed away 

 by the Artysh river up to the longitudinal axis, and thus exposing almost vertical faces. 

 These remarkably homogeneous clayey and sandy beds may appropriately be called Artysh 



, beds ; and although I could nowhere find a trace of a fossil in them, it seems to me very 



\ probable that they are of marine origin and of neogene age. 



