Show GEOLOGiCAL SURVEY COMMENDS OPHIR ARTICLE Attempt to Correlate Sedi- Sedi With Those of Tintic Tintie An article artcle by F. F M. M Wichman mining engineer en- en of Salt Lake on the mining district of Utah and which recently appeared ap sp- sp In the tle Engineering and Mining Journal Journal Journal Jour Jour- nal has brought to the author a letter leter of from th the chief of the United States S survey ad a reQuest for further data which Jin Mr lr Wichman Ichman has has forward for for- ward warded d. d The fhe portion porton of the article artcle which has ha attracted at at- at Washington ton Is that that which attempts to correlate the Ophir sedI ledl- ledl with thoss thos in applying the same names names' to similar formations In Inthis Inthis this connection the article artcle says in part On close examination a striking similarity simi sImi- larity appears However In the mineralized mineralized mineral mineral- district of Ophir that is Is I. I on Ophir Hill Hili lUl and Lion Hill HI and end in irs the adjacent canyons canyon I. I only feet of the Tintic edl ledi above the Quartzite are represo so sent d. d The formation represented In Is il what I shall Ihal call cal the Tintic quartzIte quartz quartz- Ite about OO feet of which is exposed on Cn the wall foot toot wal side o of the Ophir fault near I the base bale of Ophir hill hl It J ha has been correlated correlated corr cor cor- r related as l a Cambrian formation by some lome geologists and by others pre pro Metamorphism has ha destroyed all al fossils that the original sands may have have contained The quartzite has been brought to the sur surface surface lur face by faulting and Is exposed In only two places in two gulches located approximately In the axis ot of the anticline Overlying the dolomites at Ophir is i an Important nt limestone bed bel which Is apparently apparently apparently not represented In Tintic It I is i lo locally to- to catty cally caly called caled the tho Buckhorn Duckhorn It I Is a fine to medium grained medium rock Is nearly pure limestone lime lime- Ime- Ime Iton stone and has been the source of considerable consid l. l I erable feet reet ore are re The average thickness Is i thirty Above the tIle Buckhorn in Ophir appears the lowest of the thE ch cherty In Tintic Tintie Tin Tin- tie tic le the lowest of this type Is called caled j the tile Ajax but aside from the tile chert cherty Inclusions 1 there Is no similarity formation In I IP IU It Ophir P much U hi higher d in t tIle the series li con correlating elating It with t the e Gardner dolomite I of Ot Tintic i In the part of the Ophir district thre there occur siliceous beds at the tile base of or this formation quite quie comparable to the Victoria quartzite which underlies the Gardner Gard Garti- ncr ner In Tintic The lower tower part of the Gardner Gardner Gard Gard- ner ncr on Ophir hill hl consists of a bed of Magnesium limestone ninety to feet thick dirk gray bluish ray when fresh but weathering a a. dirty brown Higher In the tile Gardner formation the limestone becomes become more snore nasal nassir l Fossi Fossils Including large bra- bra are common at horizons horizons The total thickness of the Gardner in Ophir is somewhat over feet Overlying the Gardner but with no distinct distinct dis dIs- boundary separating them lies les what 1 is- is called caled in Ophir the Hidden Treasure lime lime- stone tone It I might be considered as the upper part of the tile Gardner but on account of its is I value as an ore bearing medium It is advisable advisable ad ad- to give it a distinct name It I form forms the summit of Ophir hill hl and ond several beds I within the formation have been very pro productive of high grade ore It I is a coarsely crystalline rather soft light gray to brownish brown brown- ish limestone The formation contains Imbedded imbedded im lot bedded layers of thin dar darg colored limestone limestone lime lime- Ime- Ime stone tone similar to that in the Gardner and at least one bed of dense carbonaceous shale The Tile last Is usually considered to be the hang hanging In wall wal of the ore bodies Fossils of ot Mississippian age ae are abundant Of this formation seventy-five seventy to lO feet is alt all al that remains at the top of Ophir hilt hill hll The comparison of the Tintic column in the Lindgren and memoir and the Ophir column from front the authors author's notes shows a a remarkable similarity for the first 2300 f feet et above shove the quartzite Above that I horizon however the Tintic column conI contains contains con con- over 2300 feet of which are not represented in the column I The missing n strata strata would indicate that there was either no deposition at Ophir be between between between be- be tween Upper Cambrian and Lower Carboniferous Car Car- or else ele a a long period of erosion preceded d the tho sediments of the lower tower car car- The he Ophir formation offers the greatest field for fol future development but the tIle upp upper r are of too great Importance importance importance im Im- im- im to be bo overlooked It I Is I possible th that t other ore zones wilt will wi be found to tile the cast of the developed zone Just Justas as in Tintic ore has been developed in depth several ml miles s to the east fast of the synclinal syn syn- trough In n fact the existence of at least one mine the old Jim Fisk Ik which produced very rich ith silver ore tin In in th the early days day is I indicative of the thc fact that ore bodies occur on on the east cast limb of the anticline anti anti- dine cline elne nearly a mile mie from Its axis The ore oreIn orein I In this mine occurred In fissures wh where re I they traversed one o of the tile Hidden Treasure beds and typifies how important certain limestone horizons horizons' are in the deposition of ore Mr fr obtained much of his hla data for tor the art articles cles while making an Inspection Inspection inspection tion of the holdings of the Ophir Silmer Simer Mines s company and during which the discovery discovery dis dis- covery WAS made as stat stated d recently in The Telegram that that a cloudburst had revealed a large largo expanse of on th the th surface o 0 the Duckhorn fissure mentioned in the article Development work ork now Is be being In conducted conduct conduct- ed by the company at this point and a camp is being constructed with wih the object of continuing development operations throughout the winter I |