Salt Lake Tribune | 1918-03-10 | Page 43 | Report by Engineer on Dugway District

REPORT DV EN6IIEH Of! DUHOISTIT Pierre Peugeot Compiles Geological Data for Smelt-j Smelt-j ing Company, j An interesting geological report, generally gen-erally applicable to the Dugway district , 1 and to the Dugway Bertha property in i j particular, has been prepared by Pierre Peugeot, consulting and constructing engineer en-gineer for the Dugway Smelting company. The report was compiled from dala gathered gath-ered by Mr. Peugeot on frequent trips to j the Dugway district during the last few monts. In connection with the geology of the district Mr. Peugeot has prepared a detailed de-tailed report concerning the Dugway Bertha. Similar reports are being prepared pre-pared on about a dozen other properties in the district. It is tVir. Peugeot's intention in-tention to make a careful examination of every property in the Dugway region and compile a complete report for the particular benefit of the smelter company com-pany and for the guidance of the various companies operating in the district. In some instances, Mr. Peugeot announces, an-nounces, the geological report already compiled will not apply, as some conditions condi-tions are local to restricted sections of the district if not to individual properties. proper-ties. . In general, however, the report covers the district. The report follows: "The geological horizon of the district is composed of sedimentary rocks, with several nearly parallel porphyry dikes cutting through them. Hence the dikes are younger than the sedimentaries. j "The sedimentary rocks belong to the J paleozoic age, and in ascending order, j starting with the Cambrian period for the I ! quartzite, with Silurian and Devonian I j limestone, as shown by fossils, tribobties ; and worm tracks in the Quartzite, orthoc-ceratite orthoc-ceratite and grapholite fossils in the Pilurian lime rocks and the various corals which I identified as of the Devonian period. "The Cambrian fossils I found in the qartzite above Nelson's cabin on the Ensign En-sign group. The Silurian fossils were found in the lime rock above the Bertha tunnel, and Lhe Devonian fossils in the lirne rock near the entrance to Bullion canyon. I further' identified the Cambrian Cam-brian period by finds of graphite on the Piedmont claim of the Piedmont Mining company. "The Bertha vein system strikes north, SO east, and dips 40 to the north in its course so far as explored. It has been crosscut in two places, the first giving lime foot and hanging walls and a width normal to the dip of about fifty feet. The second crosscut gives quartzite foot and hanging walls and a width normal nor-mal to the dip of nearly sixty feet, and the walls show slicken sides, evidencing extensive faulting. The ore shows a well- defined, banded structure in the vein, all j , of which points conclusively to a true 1 fissure vein. j "The mean water level could not be I estimated, as none of the mines in the district have developed water.- "The oxidized zone is shallow throughout through-out the district, in most instances about sixty feet below the surface in the Bertha. In the present workings it is only about thirty-five feet deep. The j oxidized ore products are a mixture of E limonite, hematite, chalcocite, bornite and 6 chrysocolla. The sulphide zone ores are F pyrite, chalcopyrite and chalcocite. The gangue is a complex silicate of alumina. I the analysis of which would indicate pyrophiilite. The ore contains small I amounts of gold and about two ounces I of silver." k