Transactions . ways, except where something can be seen of the form andstructural relations of the ore-bodies themselves. Origin of the Fissure-Ores.—Inasmuch as the bedded ores areapparently original to the beds in which they occur, we do not nir zinc- \M» LEAD-DEPOSITS l NORTB ARKANSAS. oeed to go further than these bedded deposits in search of :isource for the fracture-deposits and other water-way-deposits ofNorth Arkansas. In Borne instances the ore-deposita alongfiault-zones are below, ami in tlirr- they are above, the beddedcivs—the word above being taken in either its geologic orits hyp
Transactions . ways, except where something can be seen of the form andstructural relations of the ore-bodies themselves. Origin of the Fissure-Ores.—Inasmuch as the bedded ores areapparently original to the beds in which they occur, we do not nir zinc- \M» LEAD-DEPOSITS l NORTB ARKANSAS. oeed to go further than these bedded deposits in search of :isource for the fracture-deposits and other water-way-deposits ofNorth Arkansas. In Borne instances the ore-deposita alongfiault-zones are below, ami in tlirr- they are above, the beddedcivs—the word above being taken in either its geologic orits hypsometric Bense, or in both senses, It must be remembered that the region under considerationhas been folded Bomewhat, and has been profoundly affectedby faulting; there have also been great changes of level. In Fio. Sphalerite Brecciated Zinc-Ore in a Gangue of Chert and Amorphous Silica, from the Climax Mine. (Natural size.) addition to these internal alterations, denudation has changedthe surface-features of the entire region, cutting down throughthe rocks and modifying both the surface and the subterraneandrainage. It does not seem extravagant to Buppose that in the processof these many and great changes the meteoric waters, in theirpassage through the rocks, should have dissolved the zinc atone place and deposited it in another. In some cases theunderground waters might naturally be expected to come in 586 THE ZINC- ami LEAD-DEPOSITS OF NORTE ARKANSAS. contad with tin- bedded zinc-deposits,and to reach the Burfacebyway t faults thai penetrate both Ordovician and LowerCarboniferous beds. And it is not improbable that, in spite oftheir having been deposited at lower levels, subsequent crustal Fig. 19.
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Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectmineralindustries
