The ore deposits of Utah . cter and in chemical composition, how-ever, the ore deposition extends out from thefissure in particular beds for considerabledistances but leaves adjacent beds largelyunaffected. This selective replacement isprobably due in part to physical and in part tochemical differences in the beds. The tabular development is perhaps bestshown in the Mammoth mine deposit in the »I^indgren, Waldemar, Anhydrite as a gangue mineral: Kcon. Geol-ogy, vol. 5, p. 522,1910. massive Topache limestone, which, though itshows a pronounced swelling or extension insome beds, also replaces th
The ore deposits of Utah . cter and in chemical composition, how-ever, the ore deposition extends out from thefissure in particular beds for considerabledistances but leaves adjacent beds largelyunaffected. This selective replacement isprobably due in part to physical and in part tochemical differences in the beds. The tabular development is perhaps bestshown in the Mammoth mine deposit in the »I^indgren, Waldemar, Anhydrite as a gangue mineral: Kcon. Geol-ogy, vol. 5, p. 522,1910. massive Topache limestone, which, though itshows a pronounced swelling or extension insome beds, also replaces the intervening bedsto a considerable extent. Replacement along particular beds is wellshown in the Harrington-Hickory mine andin the mines in the limestone underlying theMowitza shale, especially the Red Warriorand Moscow mines, in which the replacementis almost exclusively along certain beds, theresultant deposits forming chimneys thatfoUow the intersection of the ore fissure andthe replaced bed. (See fig. 56.) In the de-. FiGURE 56.—stereogram showing ore shoot beneath shale. The shootfollows the intersection of the ore fissure and the limestone bed beneaththe shale. The ore makes out from the fissure along the limestone bed posits underlying the Mowitza shale the reasonfor this selective deposition seems to be largelyphysical. In the shale the fissures are tightand relatively impervious; and the ore-bearingsolutions, rising till they came to the stricture,were forced to spread out and replace themore permeable underlying beds. A similarformation of ore bodies beneath shale bedshas been noted in several localities in theWest. In the Harrington-Hickory mine thechemical composition of the beds has undoubt-edly influenced the form of the deposit. Theseries is made up of interbedded limestone,quartzite, and siliceous shales and main ore deposition has been in the lime-stone, the siliceous beds being very slightlyreplaced. The characteristic alteration of thelimes
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectminesandmineralresou
