OCR Text |
Show GEOLOGY OF SOUTH FORK COTTONWOOD Former Tintie Miner Tells Why the Section Holds (ireat Promise. One of the most attractive sections of Utah now receiving attention in a mining min-ing way is the South Fork of tho. Big Cottonwood canyon of the Wasatch range of mountains, cast of Salt Lake City. II. Barney, for many yoars .an operator of the Tlntlc and other Utah camps, Is now giving his time and attention at-tention to this Big Cottonwood section, and he has prepared a geological description descrip-tion of the camp which will be Interesting residing. This statement follows: Beginning at the mouth of South Fork and going almost due south up the canyon, can-yon, one will see to the cast an abrupt ridge caused by an upheaval benching the rocks up and leaving them tilted and exposed and standing like huge marble stairs. In this terrific upheaval it Is very apparent that resistance to the west was loo great, consequently a huge normal fault extends tho entire length of South Fork and through the ridge and down Superior gulch Into Little Cottonwood Cotton-wood ennyon. This uplift exposes to view the edges of a sorlos of sedlmontary or stratified rocks, which arc slightly anttcllncd, the axis of which Is tho wist and west dividing ridge between the head of South Fork and Little Cottonwood Cotton-wood canyon, the trend being north and south and pitching about 30 degrees to the cast. Serios of Hocks. These rocks consist at tho base of exposure ex-posure of (iiiartzlte for about 300 feet; then coii)C3 about 100 feet of basaltic rook, on top of which Is twonty-fivo feet of conglomerate. 500 feet of quarlzlte. fifty feet of hornblcndo schists, and 600 feet of lime rock. It Is in the above described rocks that it Is said the Columbus Colum-bus Consolidated ore bodies arc found; also the Columhus Extension. The ores of those properties arc said to form in the quartzite with the trap rock in the hanging wall. The old Flagstaff and Kennabeck ores aro also found In the upper llmos of these series. The ores of the Cardiff are found In the lower quartz-Ito quartz-Ito west of the dolerlte. This oro Is found In a fault llssuro caused by the branching up movement. The ore from ail appearances has boon drugged Into the fissure at the time the faulting accrued, ac-crued, showlnpr conclusively that there must have been a strong bedded deposit broken at the time of faulting. At tho Cardiff the company has followed fol-lowed by tunnel the strike of the main fault line 1400 feet, where It shows plainly plain-ly thai the edges of the lower quartz-Ites quartz-Ites have been brought up in contact with the edges of tho upper limes which have hung back from tho resistance to the west. The writer has no doubt that I In the sedimentary rocks and near the trap dike that large bedded doposlts of ore will bo found. Key to Drain Tunnel. Throughout tho above series there aro numerous Igneous and cross fissures, which arc usually very productive, especially es-pecially where they intersect the trap dike. Take, for Instance, the old Toledo To-ledo cross fissure, which produced upwards up-wards of a million dollars in the early days of Alta, tho workings of which arc in and near tho trap dike. The above series of rock arc easily traced from the Columbus Consolidated in Alta through the Columbus Extension, Rexall, Cardiff, Car-diff, Kennabcck, Tar Baby. East Carbonate Car-bonate and the Bramberg brothers' Contention Con-tention group of claims. This group of claims holds the key to a drain tunnel site along the strike of this great and long neglected mineral zone. The gcnoral conditions at tho Tar Baby are Ideal for large ore bodies, having a fifty-foot porphyry dike cutting the stratified rock at right angles and visible for 2000 foot. The writer understands that it is on this dike that the Tar Baby company Intends running Its tunnel. If so, there Is not much doubt that the days of the old Toledo. Flagstaff and Kennaheck will be repeated to the west of this great fault. Erosion has played a very activo part. Great blocks of the upper limes have been carried away, leaving baro the underlying un-derlying quartzltcs, and this is found to be so at the old Park City group, and Just north at the Bramberg brothers' proporty the limes have been spared, and again Just north there Is a slight lateral fault, which fault, assisted by erosions, are responsible for tho exposure of the Old Carbonate oro body, from which so much ore was shipped in the early days of the Cotlonwoods. Tho Carbonate Car-bonate oro bodies are bedded deposits in tho lime near tho quarlzlte lime contact. |