46 RESEARCH IN CHINA. 



stone of sufficiently definite character to justify the identification of it and 

 other limestones of the region as belonging to that system. 



In the preceding pages the occurrence of the early Paleozoic (Sinian) 

 strata has been described for various districts of China, from the province 

 of Liau-tung, latitude 41, to the Yang-tzi in latitude 30; and from the 

 eastern plains of the empire to the central Ts'in-ling-shan, in longitude 108. 

 It remains to consider the probably equivalent terranes which are known 

 in the Himalayas. 



In southwestern China rocks of early Paleozoic age, if they occur, are 

 highly metamorphosed and have not yet been definitely recognized. It is 

 not until we reach the central Himalayas, in longitude 80, that we have 

 any precise information. Thence westward, in the regions covered by 

 Griesbach* and Hayden.f there exists, on the basis of fossils, definite 

 evidence of the presence of the Upper Cambrian, which is underlain 

 by a considerable thickness of conformable strata, presumably also of 

 Cambrian age. 



Griesbach calls these strata by the local name Haimantas, and gives 

 the following classification for the eastern area: 



In descending order: 



Silurian : 



3. Series of quartz shales and slates. 



2. Shales and silky phyllites, with great thickness of quartzites. 

 Haimantas : 



i . Quartzite, generally purple, with great thickness of conglomerate. 

 Vaikritas and older gneiss. (Pre-Cambrian.) 



The total thickness is estimated at about 4,000 feet, 1,200 meters. The 

 base where the Haimantas come in contact with the Vaikritas exhibits no 

 sharply defined plane of division : 



At Milam, for instance, there is seemingly a very gradual passage from the micaceous 

 schist south of that village, into greenish-gray phyllites and talcose schists with garnets of 

 the Vaikritas, and finally into the thin-bedded quartzites, shales, and conglomerates of the 

 Haimantas, and the change is so gradual that the boundary line could not be drawn with 

 anything like accuracy.! 



Regarding the conglomerate, it is said (page 51) : 



The thick deposits of a coarse conglomerate and breccia are mostly made up of rolled 

 and subangular fragments of rocks belonging to the crystalline area, and amongst them 

 large boulders of quartzites and gneissose rocks seem to predominate. The matrix in which 



* India Geological Survey Memoirs, vol. xxm, Geology of the Central Himalayas, by C. L. Gries- 

 bach, 1891. 



\Idem, vol. xxxvi, pt. I, Geology of Spiti, with parts of Bashahr and Rupshu, by H. H. Hayden, 

 1904. 



%Idem, vol. xxm, p. 51. 



