This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1911 Excerpt: ...to the immediate vicinity of the limestone areas. The veins in which calcite is the main filling are seldom extensive either horizontally or vertically. They appear to be formed usually as the result of shearing and infiltration of the calcite derived from the adjacent limestones. Plate XII, B (p. 66), shows a portion ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1911 Excerpt: ...to the immediate vicinity of the limestone areas. The veins in which calcite is the main filling are seldom extensive either horizontally or vertically. They appear to be formed usually as the result of shearing and infiltration of the calcite derived from the adjacent limestones. Plate XII, B (p. 66), shows a portion of the Paleozoic limestones on the east coast of Darby peninsula, where an intricate network of calcite veins forms a stockwork through the brecciated limestones. Although the veins are slightly more numerous in this view than in the majority of exposures, the arrangement and general characters are quite typical. Plate VIII, A (p. 46), already referred to, shows other calcite veins of the same general mode of occurrence near a greenstone intrusive. Some of these veins are undoubtedly younger than the intrusion of the greenstones, as they cut them or occupy joint planes in them, and it is believed that most of the veins were produced either during or subsequent to the deformation of the Paleozoic rocks. Calcite is practically the only mineral found in the calcite veins. No sulphides or other metallic minerals have been noted in them, and they are consequently, in this region, of no economic importance. At least two distinct series of quartz veins have been recognized in the region; in one the veins are much contorted and sheared, in the other crystalline quartz with characteristic comb structure is found. This difference in structure is to be explained by the difference in age of the two types. It seems evident that to have been crushed, sheared, and otherwise deformed the veins must have been in existence at the time of the post-Paleozoic deformation, whereas on the other hand the slightly sheared, relatively undisturbed character of the other...
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Add this copy of A Geologic Reconnaissance in Southeastern Seward to cart. $38.96, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2018 by Palala Press.
