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. 1852 Excerpt: ...and occupies a considerable surface extent between the Jaltepec and Jumuapa, south of the limestone. Its direction is described further on. Commencing at a point where the" Bio Pachine joins the Malatengo, and thence in a southeasterly direction, are a range of porphyritic hills with metamorphic sandstones, claystone, ...
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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. 1852 Excerpt: ...and occupies a considerable surface extent between the Jaltepec and Jumuapa, south of the limestone. Its direction is described further on. Commencing at a point where the" Bio Pachine joins the Malatengo, and thence in a southeasterly direction, are a range of porphyritic hills with metamorphic sandstones, claystone, and jasper, extending as far as the Arroyo de los Otates, where it falls into the Chihihua; these have the same dip, and look with their bluff faces in the usual northerly direction. In the passes between these hills run the rivers which follow the general slope of the sandstone. In that portion of the range west of the Malatengo river, and near San Juan Guichicovi, iron ore abounds. Between these hills and the Malatengo Eiver, after it has taken its easterly course, the compact limestone, described previously, crops out upon the surface in several places along the line of survey. Between the Malatengo and the Sarabia, and between the latter and the Jaltepec, the surface is less disturbed: granular quartz, or quartz-breccia, sandstone, and porphyritic greenstone and sandstone are the underlying rocks. JSTone of these upheavals reach the height of the hills more to the south. "While the direction of the elevating force was the same, its intensity was less. The real inequality of the surface is diminished by the accumulation of quartzose gravel and gravelly clay, which here occupy the whole surface of the level ground. Five miles south of the Jaltepec the compact limestone appears as the surface rock. Here it overlays coarse conglomerate, consisting of hornstone united by a calcareous cement. The limestone forms the crest of an elevated ridge dividing the waters of the Jaltepec and Jumuapa. It has a porous structure, but is rather hard...
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