The ore deposits of Utah . copper and zinc. REPLACEMENT DEPOSITS. Practically aU the deposits of the districthave formed as replacements of certain beds oflimestone in typical shoots or pipes followingthe intersections of the replaced beds and theore-bearing fissures. In detail, however, theydiffer considerably. In some replacement hasextended for a considerable distance from thefissures and has formed tabular bodies of ore;in others it has formed relatively small position of the ore shoot is largely con-trolled by the position of the replaced hmestonebed and the ore fissure. Most of
The ore deposits of Utah . copper and zinc. REPLACEMENT DEPOSITS. Practically aU the deposits of the districthave formed as replacements of certain beds oflimestone in typical shoots or pipes followingthe intersections of the replaced beds and theore-bearing fissures. In detail, however, theydiffer considerably. In some replacement hasextended for a considerable distance from thefissures and has formed tabular bodies of ore;in others it has formed relatively small position of the ore shoot is largely con-trolled by the position of the replaced hmestonebed and the ore fissure. Most of the fissuresare very steep, and many of them are nearlyvertical, but the dip of the limestone bedsvaries greatly, and this dip governs the pitchof the ore shoots. ALTERATION OF THE LIMESTONE. In some places the alteration of the lime-stone by the ore-bearing solutions consistsmainly of a replacement of the rock by thesulphide minerals forming the primary ore. In 17. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 111 PLATE XXXVII. A. SPECIMEN OF ROCK FROM THE OPHIR HILL MINE, SHOWINC; ALTERATION OF LIMESTONE THAT CONTAINS ORE DEPOSITS. Layers containing crystals of pyrite are composed largely of epidote with orthoclase and quartz; intervening bandscomposed largely of quartz and orthoclase. Two-thirds natural size.
Size: 1762px × 1418px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectminesandmineralresou
