The deposits of the useful minerals & rocks; their origin, form, and content . formation, and are only found where solutionscirculating along fissures and boundary-planes encountered calcareousand dolomitic rocks, such rocks being chiefly Carboniferous, but alsoDevonian. It is seldom that any ore is found in the arenaceous slatesabove or below these limestones. Still more unfavourable to the de-position of ore do the Carboniferous slates appear to have been, since \viththem ore is only known to occur in connection with the Bleiberg fissure-system. Somewhat more favourable were the foot-wall sl
The deposits of the useful minerals & rocks; their origin, form, and content . formation, and are only found where solutionscirculating along fissures and boundary-planes encountered calcareousand dolomitic rocks, such rocks being chiefly Carboniferous, but alsoDevonian. It is seldom that any ore is found in the arenaceous slatesabove or below these limestones. Still more unfavourable to the de-position of ore do the Carboniferous slates appear to have been, since \viththem ore is only known to occur in connection with the Bleiberg fissure-system. Somewhat more favourable were the foot-wall slates of the Upper ^ Gesellschaft filr Bergbau, Blei- und Zinkfabrikation zu Stolberg und in Westfalen. 732 OEE-DEPOSITS Devonian in which, as for instance in the Schmalgraf, Lontzen, and Prestermines, and at Hammerberg near Stolberg, etc., ore-bodies are occasionallyfound. Such faults may be followed right through all the Palaeozoic beds, fromthe Cambrian to the Carboniferous, even though at times they may berepresented only by fiucans or narrow fractures. The width of the. Cretaceous Zinc oxidized ore. Slate with arid Diluvium. Galena. Slate. Clay andIronstone. Fig. 345.—Horizontal and cross sections of the St. Pauli lead-ziuc mine at Welkenraedt. fissure in the limestone is different from that in the clastic rocks, whileat the same time the mineralization has almost always changed. The strikevaries between east by south and south, a bent course being seldomobserved. Generally several fissures occur together, in part with theircourses parallel and in part diagonal, so that they form a fissure- orUnked series. Often again, a fissure, simple and regular in one part ofits course, is observed to split up along its continuation. The length of these transverse faults is quite considerable, the Miin-stergewand and the Sandgewand faults, for instance, cross not only the THE METASOMATIC LEAD-SILVER-ZINC DEPOSITS 733 Carboniferous syncline at the river Worm, but also
Size: 1756px × 1424px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectminesandmineralresou
