GEOLOGICAL SUEVEY OF THE TEEEITORIES. 105 



of about 45°. The effect of erosion here has been to so level these beds 

 that it is difficult to trace the succession of the various layers. 



We made several excursions while at Golden City, one of which was 

 up Clear Creek Canon, through which the Colorado Central Eailroad, 

 a narrow-gauge road, runs. When finished it will penetrate to the min- 

 ing-districts of Georgetown and Central City. When we visited it 

 the road-bed was graded some ten miles above Golden City. The creek 

 has cut its way through the hills in a tortuous course, leaving high 

 walls of gneiss and granite standing on either side. In the gneisses I 

 obtained garnets and magnetite. There has been some gold-mining 

 carried on in Clear Creek CaQon, but I judge it was with but little profit. 

 At any rate, at the present time the diggings are abandoned. 



From the office of the Colorado Central Eailroad I obtained speci- 

 mens of ores from Central City, consisting mainly of gold quartz, 

 pyrites, and argentiferous galena. 



Having completed our work we left Golden City and started for Ogden, 

 Utah Territory, where we joined the main party in camp on the 8th of 

 June. The Wasatch Eange, at the foot of which the town of Ogden is 

 built, has a trend north and south. Its geological structure is beauti- 

 fully shown in the many caiions which cut deeply into it almost at right 

 angles to the trend. It is in these canons that the profitable mines of 

 Utah are situated. The canons near Ogden are Ogden Caiion and 

 Weber CaSon. Through the latter the Union Pacific Eailroad finds its 

 way into the Great Salt Lake Basin. Between these two there are a 

 number of smaller caiions which cut the mountains onlj^ partially. Two 

 of these, immediately back of our camp, are Taylor's Caiion and the 

 Waterfall Canon. In the former there is a limekiln in operation. Here 

 also some miners claim to have discovered tin. An examination of 

 specimens i)roves, however, the absence of any metal and showed the 

 specimen to consist almost entirely of hornblende. The Waterfall Caiion 

 is named from the occurrence in it; of a fall some 300 feet in height. 

 The water falls over a ledge of white qnartzite. Above it rises Mount 

 Bechler, whose height is 9,716 feet. The base of the mountains near 

 Ogden is for the most part a red syenite, whose specific gravity is about 

 2.6. This syenite passes into granite and gneiss. It contains, in places, 

 veins of hornblende, and the gneisses have veins of quartz with specu- 

 lar iron. Several of these veins have had openings made into them by 

 prospectors. The largest is just south of the Waterfall Caiion. It is 

 four feet in width and i^enetrates the rock to a depth of thirty feet hori- 

 zontally. The walls on either side are gneisses, stained with the green 

 carbonate of copper, (malachite.) Thegangue is quartz and serpentine. 

 Associated with the sijecular iron or micaceous hematite are iron j)yrites 

 and staiuings of copper. The iron is in veins varying from the fraction 

 of an inch to two inches in thickness. On the north side of Ogden Caiion: 

 I found another opening, much smaller, in chloritie schists, which, at 

 this point, lie just above the syenite. The gangue here was white 

 quartz, containing veins of micaceous hematite. The schists contained 

 numerous veins of quartz. Above the metamorphic rocks there are heavy 

 beds of quartzite, the lower bed of which is conglomerate, the siliceous 

 matrix containing pebbles of bright-red jasper. The qnartzites have a 

 specific gravity of 2.6 and are mostly of white color, although in some 

 places they are pink and again dark brown, becoming highly ferruginous-.. 

 Above thequartzites are heavy bed's of dark-blue magnesian limestones of 

 Silurian age, above which are Carboniferous limestones. I was shown a 

 specimen of graphite from near North Ogden, a village six miles abov^S' 

 Ogden. At the upper end of Ogden Caiion galena is found associated 



