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646 °  STRATIGRAPHICAL GEOLOGY. [Boos VI. 
fossils have yet been found in them; but they must be much younger 
than the Laurentian rocks, on which they rest unconformably, and from — 
which they have been in part at least derived. 
Crystalline gneisses, schists, and other associated rocks occur, as in 
Europe, in the cores of many of the chief mountain ranges of North 
America, and have with more or less confidence been assigned to the 
Archean series, for example, in the Appalachian chain, and in many of 
the separate ranges comprised among the Rocky Mountains. It is 
probable, however, that some of the rocks included in this reference are 
metamorphic rocks of much later date. In the Wahsatch Mountains, 
Utah, certain granites, included as Archean, have been shown to be 
younger than the Carboniferous period.! 
India.—In India the oldest known rocks are gneisses which underlie 
the most ancient Paleozoic formations, and appear to belong to two 
periods. The older or Bundelkund gneiss is covered unconformably by 
certain “ transition ” or ‘‘ submetamorphic ” rocks, which, as they approach 
the younger gneiss, become altered and intersected by granitic intrusions. 
The younger or peninsular gneiss is therefore believed to be a meta- 
morphic series unconformable to the older gneiss. In the western 
Himalayan chain there are likewise two gneisses—a central gneiss 
probably Archean and an upper gneiss formed by the metamorphism of 
older Paleeozoic rocks into which it passes, and which lie unconformably 
on the older gneiss and contain abundant fragments derived from it.” 
New Zealand and Australia.—In the South Island of New 
Zealand the most ancient Paleozoic rocks are underlaid by vast masses 
of crystalline foliated rocks traceable nearly continuously on the west 
side of the main watershed. They consist chiefly of varieties of gneiss 
which are coarse and granitoid in the lower parts. In Canterbury there 
is a central zone of micaceous, talcose, and graphitic schists overlaid by 
chlorite- and hornblende-schists, and lastly by a quartzitic zone interleaved 
with schists.? Similar rocks run southward through the west of Otago. 
The centre of this province is occupied also by a broad band of gently 
inclined mica-schists. These rocks—the main gold-bearing series of 
Otago—are believed by Captain Hutton to be not less than 50,000 feet 
thick, and are referred by him to a later formation than the more 
crystalline gneiss;* but Dr. Haast regards them as only the upper part 
of the great fundamental granitic gneiss of the island. 
In Australia large areas of granite and of crystalline-schists occur, 
but their precise relations have not yet been worked out. Some of these 
rocks have been described by Selwyn, Ulrich, and others, as metamor- 
phosed Paleozoic formations. But there are not improbably other areas 
referable to an Archeean series. 
' Amer. Journ. Sci. xix. (1880), p. 363. 
* Medlicott and Blanford, “ Manual of Geology of India,” pp. xviii. xxvi. But there 
are younger Indian schistose rocks from which these must be distinguished. In the 
Himalayan region there is a series of gneisses and schists below which lie comparatively 
unaltered beds of supra-triassic age. P 
* Haast’s ‘‘ Geology of Canterbury,” p. 252. 
* “ Geology of Otago,” p. 31, 
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