Arizona republican., 1914-05-31

to It's industrial welfare. One of the first pieces of work in this direction resulted from the admira ble mapping of the Midland coal field by Beete Jukes, a distinguished member of the geological survey of England and Wales. The entire correctness of his theories was demonstrated by Henry Johnson in deep sinking at LandWell Park. when the first definate proof was furnished of the prolongation of the South Staffo1dshire coal field to the east under the fringe of overlying red rocks
 Similarly, the discovery of a buried coal field in the southeast of England was the direct result of a piece of pure scientific deduction Goodwin in the Palaeozoic floor, by which the existence of coal basins are determined, would be traceable, even when covered by great thickness of newer rocks; because a line of disturbance. whether of faulting CT folding, when once established, tends to be the loens of subsequent movements and thus to set
 
 The correctness of this tectonic prin- ciple was demonstrated by the success ful bOringS carried out in the neigh borhOod of Dover, first by Sir Edward Watkin. ard later by the Burr com panies under the scientific advice of Professor w. Boyd Dawkins and other geologists. These borings showed that ha tertiary strata, is a coal field situated on the line connecting the seams worked in northern France and Bel gium with those of south Wales and Bristol; and it appears not improbable that other coal areas might be found II the underground geology of this line of country were systematically ex- plOred.
 A satisfactory feature of the discov- cry of buried coal fields in England is the large addition thereby made to British coal resources as to which pre- vious estimates had been rather pessi- mistic.
 Another instance of the successful aspiration of geology to mining is furnished by the tracing eastward and southward of the sub-outcrop or apex ol the Rand banket formation under a cover Of up to 1900 feet of later un- conformable beds. The investigations that led to this result were based on a geological survey of the country be- tween Rocksburg, the Springs and Hei- delperg, the first results of which made It probable to me that the Van Ryan congiomerate. which disappears near the springs beneath the Karroo coal 1 measures and the Nigel conglomerate | emerging therefrom near Heide,herg were geolOgically identical. althoueb ! separated hv larqe area in which do'omite and coal measures from the surlace as my work progressed the losltlon that the two outcrops with i their opposed dips, were respectively the northern and southern lips of 2 large but shallow synclinal basin became almost certainty, and deep porlngs made in the intervening country, confirmed in the en1 the correctness of the theory in the most satisfactory manner.
 The successful outcome of these investigations added to the Wit Waterstrand gold field an enormous area of mining ground, in which the banket is not too deep for exploita ton, should it's average gold content prove hlsh enough to enable it to be Fro1ltabiy extracted, a consumma uon, Of course. devoutly to be wished but only demonstrable hy smart sinking and development. since assay results of bore-ho cores are nc guide to average values. The deepest bore hole of the series unde, my immediate supervision. namely that put down on the boundary a, the farms Grootvlei and Dappafon tein. was practically on the axis ot |, the syncline and cut the main rect at a depth of 5,540 feet. It passed through 1,140 feet of dolomite be. fore entering the Witwaterstran Iormatlcn, but gave a most instruct I've section of the latter, intersectinc the Kimberley, Bird, Modderfonteir ana Van Ryn. or main reef serie oi conglomerates and their associ ated quartzites, slates and sheets o [ -' oON"i uidDdSe- Al the tim Of boring the whole of the core abou mile in length. was careful, labeled and preserved on the prop ! erty in a specially constructed cor ] house
 The limited time at my disnosa will not allow me to recapitulat , more than a few of the importan n services rendered in recent years f mining by geologists. But mentio,
 must be made of E. J. Dum's surve
 Of the Bendigo gold fields and hi
 brilliant exposition of the true ma
 ture of the remarkable saddle reef,
 whose tectonic structure has deter
 mined a type of mine developmen quite peculiar to that field.
 Again, S. F. Emmons' monogram
 on the structure and genesis of tn
 Leadville silver-lead ores has bee
 of enormous value to the Colorad ! mines, not a few of whom owe thej
 success in that field to the predica t tions of the distinguished economi ], geoiogist. whose recent demise w : must all deplore; on the other hant
 the theory advocated by Emmon. f that the ores were derived from met n als leached from the overlyin |. porphyries, and the consequent con n clusion that the lower or whit e limestone would prove unproductiv n have DrODably somewhat retardad tb