...however, it forms comparatively thin beds, associated with beds of shale.'-' The beds of coal vary in thickness from a fraction of an inch to several feet ; and, in some instances, beds havo been found measuring forty and even fifty feet in thickness. Thc averago...

...case, hewever, it forms comparatively thin beds, associated with beds of shale.* The beds of coal vary in thickness from a fraction of an inch to several feet; and, in some instances, beds have been found measuring forty and even fifty feet in thickness. The average...

...case, hewever, it forms comparatively thin beds, associated with beds of shale.* The beds of coal vary in thickness from a fraction of an inch to several feet; and, in some instances, beds have been found measuring forty and even fifty feet in thickness. The average...

...Hind asserts, exceeding 4,000 square miles. These bands contain numerous veins or " leads," varying in thickness from a fraction of an inch to several feet, and it is only in certain localities, as discovered so far, that the auriferous deposits and decomposed...

...formation. I.it/iolof/ic i-liiifiicter. — Four zones, the upper three each approximate 1\ 12,500 feet in thickness, the lowest at least 1,200 feet...sand grains are largely quartzitic and the pebbles granit ic, as they are also throughout the remainder of this and the succeeding (Sespe) formation....

...Range in this district, Eldridge's name has been employed to designate the latter formation. Lithologic character. — Four zones, the upper three each approximately...scattered fish integuments, and what are supposed to be ostrscoda. The second zone is similar to the first except that in the second the sandstones are relatively...

...rocks are seen to be composed chiefly of very fine alternating siliceous and argillaceous layers that range in thickness from a fraction of an inch to several feet. Some of the harder gray siliceous layers resemble chert, and some of the softer argillaceous ones a...

...region of Southern California it is largely exposed, and is thus described by Arnold (op.cit.p.22) : "Four zones, the upper three each approximately 2,500...ostracods." "The second zone is similar to the first except that in the second the sandstones are relatively much more important than the shales, some of the sandstone...

...alternating layers of different quality coal, such as hard and soft or bright and dull coal. Partings range in thickness from a fraction of an inch to several feet. Where partings exceed two feet it is seldom that more than one bench of the bed is recovered and the...

...alternating layers of different quality coal, such as hard and soft or bright and dull coal. Partings range in thickness from a fraction of an inch to several feet. Where partings exceed two feet it is seldom that more than one bench of the bed is recovered and the...