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HAYDEN: GEOLOGY OF SPITl. 
Chapter II. 
CAMBRIAN SYSTEM 
A glance at the map will show that the Spiti valley has a general 
N. W. — S.-E. trend, to which the strike of the sedimentary rocks 
to a great extent conforms. With this strike is combined a north- 
erly dip : hence the outcrops of the various systems form a series of 
bands, the oldest lying to the south. 
The most southerly band constitutes a part of the oldest known 
sedimentary system in the Western Himalayas, and to a large extent 
forms the great snowy range separating Spiti from Kulu and Bashahr. 
It has been designated by a variety of names, the best known of which 
are "Azoic" (Strachey), " Bhabeh series" (Stoliczka) and " Hai- 
manta " (Griesbach). 
Before passing on to a description of this system, as seen in Spiti, 
Metamorphic rocks. it is necessary to notice certain beds which are 
Gneiss. said to underlie it in other parts of the Hima- 
layas. These are Mr. Griesbach's "vaikrita" system, and the so- 
called " central gneiss." The latter rock has been found by General 
McMahon to be in reality a gneissose granite : it is seen throughout 
the Sutlej valley from Wangtu to Shipki, and again along the Spiti 
river, and at Changrizang on the lower Para river, one of Stoliczka's 
type-localities, where it is found intrusive both in cambrian and permian 
beds. 
The other series described by Mr. Griesbach from the Niti area, as 
Schists of Wangar °^ probably pre-cambrian age, is the vaikrita sys- 
valley; tem, composed of schists, talcose rocks, phyliites 
and gneiss. From near Wangtu bridge on the Sutlej to within a short 
distance of the Bhabeh Pass, the road passes over a complex series 
of mica-gneisses, kyanite-schists and garnetifcrous mica-schists, with 
basic igneous rocks and much intrusive granite (central gneiss). The 
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