414 J. W. Powell—Types of Orographic Structure. 
Art. XLV.—Types of Orographie Structure; by Major J. W. 
POWELL. 
west,—-the Park Province, the Plateau Province and the Basin 
Province. The first is described as including the great parks of 
Southern Wyoming, Colorado and Northern New Mexico, and 
a great development of metamorphic crystalline schists, mostly 
ins of marine and 
North America, and also in its displacements 
or uplifts; moreover, Cenozoic and Mesozoic rocks prevail, thoug 
some of the important plateaus are of Carboniferous beds, and m 
places the subjacent rocks even down to the Archean are exposed 
to view in consequence of erosion, , 
The Basin Range system includes the Great Salt Lake ee 
and other valleys and ridges extending through Western tah, 
Nevada, Southeastern California and perhaps across the Colorado 
in Western Arizona; and embraces Paleozoic beds as well as 
metamorphic schists, along with eruptive beds, some of which are 
the principal component parts of the ranges.] 
which are adjacent to the anticlinal axes as having been UP 
es as havil 
thrown. In such cases I do not wish to commit my self 
