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Show COAL RESOURCES ON WASATCHPLATEAU In order to obtain information' for use in the proper apportionment' ot Goverment lands into leasing Units under the terms of the Leasing Act of 19 20 a party of the United States Geological Survey, under the direction direc-tion of E. M. Spieker, made a detailed detail-ed study last summer of the thickness and distribution of the coal beds and ithe quality of the coal in theWasatch r'mieau, Utah. The party included inclu-ded H. I. Smith and G. J. Salmon, mining engineers of the United States Bureau of Mines, who studied the engineering problems bearing on the mining of the coal; W. B. Upton, Jr.. G. F. Harley, and F. W. Downey, topographic engineers; and E. M. Spieker, W. W. Beyer, and R. H. Haseltine, geologists. . Most of this field is on the Wasatch Plateau, between be-tween 7,000 and 10,400 feet above sea leavel and between 4,000 and 5,000 feet above Castle Valley, to the east. The area most thoroughly studied and mapped lies in the eastern east-ern part of the plateau, between Wildcat Canyon, in T. 13S. H. 8E. and the mouth of Huntington Canyon inT. 17S., R. 7E. The Wasatch Plateau is for the most part a broad iipland, whose surface sur-face shows smooth, gentle slopes but whose eastern front is marked by steep sandstone cliffs, which' rise 1,000 to 2,000 feet above adjacent i Castle Valley. These clifs, are in places breached by the deep canyons of streams which extend back as far as 35 miles from the front of the cliffe. The coal-bearing strata, which belong to the Mesaverde crop out in a sinuous line along the. oold escarpment at elevations ranging rang-ing generally from 700 to 1,200 feet above the bordering lowland. The difficulty of bringingg the coal down from its outcrop in the steep headlands that mark the outer line of cliffs has generally discouraged dis-couraged development, and consequently conse-quently all the mines along the escarpment are in cahyons whoso gradient is not very steep At such places the mining camps of Castle-gate, Castle-gate, Mohrland, Hiawatha, Wattia, and the towns in Spring Canyon and Pleasant Valley have been established, estab-lished, but even at these places it has been necessary to construct long and expensive tramways to reach most of the mines on the east escarp-. ment of the plateau. There are few ' places on the escarpment at which the coal beds outcrop at tippleheight on a possible railroad grade, but. In. : some of the small canyons tributary,, to Huntington Canyon it will ho possible to reach the outcrop of the lowest coalby railroad. The development of the field has merely, begun. Even some of. tho older mins, such as those at Castle-gate Castle-gate and Clear Creek, which havo been operating for more than thirty yeara, have reserves before theui sufficient to exceed their past outputi and the possibilities of certain unde, . veloped areas, such as Huntington. Canyon, are barely suggested 6y the, present output of the field. The workable coal beds of the Wasatch Plateau occur in the Mesaverde formation, which U from 1,300 to 2,000 feet thick and which consists of sandstone, shale, coal. .The lower part af the Mesaverde contains no coal, and the examination examina-tion made last summer showed that It is marked by a massive, resistant resis-tant sandstone 50 to 100 feet thick, which forms a sheer cliff wherever , It is above drainage level. The middle member, 600 to 900' feet thick, contains the workable coal (Continued on last page.) COLE RESOURCES Oil WASATCCH PLATEAU (Continued from first page.) beds and consists largely of inl-stone inl-stone and shale in iroughly equal proportions. ' Its lower limit la normally no-rmally marked by a white sandstone, from 5 to 60 feet thick, an unusually clear and persitent "key" bod, which can be as easily traced as the baaal sandstone wherever It is exposed. The lowest coal bed either rest directly di-rectly upon this sandstone or lies a few feet above it. The overlying sandstone and shales contain a large number of coal beds, some of which maintain workable thickness o'er considerable areas and at least one of which is commercially vsJoW nearly everywhere in the field. Directly above the middle member lies the thick cliff-making sandstone that forms the Castle Gate in Price River Canyon, an object whose scenic attraction has loaz been appreciated by tourists. Throughout most of the field the beds lie very nearly horizontal or dip at low angles. ' In its northern part, between Castlegate and the North Fork of Gordon Creek, they dip to the northeast at low angles; to the west, in Pleasant Valley,, they dip to the north and northwest; In Bob Wright Canyon, IB miles due west of Price, they are nearly horizontal; hori-zontal; to the south, in the east escarpment, es-carpment, between Star Point, itt T. 15 S., R. 8 E., and the niounth of Huntington Canyon, in T. 16 8., R. 8 E., they dip southwestward at very low angles, and in Huntington Canyon Can-yon they dip southward at an angle somewhat less than the gradient of Huntington Creek. In short, the northern part of the Wasatch Plateau Pla-teau coal field is structurally a broad low half-dome, with its center in the northern part of Bob Wrlht Canyon. Can-yon. ,The rocks in certain parts of the field are much faulted, and at som9 localities the faults affect Berlously the disposition and mining of the coal beds. All the larger faults were located and measured, and It is believed also that practically all the many determinable smaller fault3 are known. They are all of the normal type that is, they are breaks in the strata caused by .K,ki.1(r nnnfmf.H In thrusting or compression, and they involve the simple dropping of the beds on one side of the break with reference to those on the other. In the drainage basin of the North Fork of Gordon Creek the faults are somewhat complex. - One large fault, which is just east of Coal Canyon, in sees. 16 and 21. T. 13 S.. R. 8 E.. and which trends very nearly due north, brings the con! down from its high elevation in the rkle east of Coal Canyon to ,vi easily attainable attain-able height in the North Fork of Gordon Creek. Numerous smaller faults, which trend in diverse directions, direc-tions, cluster about the major fault, so that very detailed geologic study of the' central and western parts of T. 13 S.. R S IS., should bo mad-before.' mad-before.' actual mining is started. A few faults occur in the drainage-basin drainage-basin 'of the South Fork of Gordon Creek., and some have cau-.el displacements dis-placements of as much as 100 feet or more. In the long s:rip of territory between. be-tween. Pleasant Valley nnd the mouth' of. Huntington Canyon there are at least three faults that have a displacement of more than 1.000 feet, as well as a host of sniallei ones. ; Pleasant Valley lies alone the most notable north-ward-trend ins fault, by v. hiih the beds on t li - east have been dropped at leas'. 1,000 fee!, until the lowest coal bed is only a few feet above creek level on the east side of the valley, at the town of Clear. Creek, wheieas on the we"i side it is high in the hills. A faulted kene accompanies t,ie major fault throughout the strip mentioned, mention-ed, and the adjacent region parallel to it i3 broken by smaller faults tha' have the same general dire '.i'M. Near the mouth of Ilunti -i:toii Ca'i-yon Ca'i-yon is a zone, in which minor faults are numerous. These I'.ielts. a? well as all the major fault.; in the field, trend very nearly nor; hv. aril. .The faults affect mining opeation-considerably, opeation-considerably, for they break the con tinuity of tr.u-.lwl3. and thus they either make""' iVercssa ry expensive slopes or pliaUs to leach the coil bevond or they make it e; oiiomi'-all' impossible to continue the miir? b''- youd the fault. They are thus of particular consequence in undevelop-ei undevelop-ei areas, and they have threrefore ei.eivd special consideration by the geologists in the work of providing adequate data for the distribution I of the laud into leasing unites. The Coal I The coal of this region is of cx-' cx-' eellent quality and is highly esteem- ed by the users of western fuels. It I is hard, black, and lustrous, with-j with-j stands weathering and transportation transporta-tion well, and is otherwise physically well adapted to meet the needs of the trade. It has a high calorific value, a moderate percentile of ash. and a very low percentage of sulphur. sul-phur. The results of many analysis made by the United States Bureau of Alines show that it maintains its hitch quality throughout large areas. Most of it is a h'ghly satisfactory domestic fuel, largely because of its clearness and permanence in lump form, and small mines have for many years supplied i: to consumers throughout the field. Many of the large mines now in operation were besun at the sites of old "wagon" mines. The number of beds more than 5 feet thick ra; i;es from one to four in different parts of the field. Localities Lo-calities in which theie is not at least one bed 5 feat" or more thick are exceedingly rare. At many places tlie total number of beds is large; a complete sectio of the coal-barieng lumber in Corner Canyon, in see. 12, T. 15 3., R 7 E., shows twenty coal beds, but only fiv eof them are over 2 feet thick, and only three are f feet cr more thick. The maximum thickness attained : by any known bed iu this field is i 30 fee'. .This hugs bed lies at the j base of the coal measures in Pleasant ! Valley, in the immediate vicinity of I Sehofield, where it -is mined by the ; Uunion Pacific Coal Co. The lower i bed is 28 feet thick at places in the ; Mohrland mine of the United States Fuel Co., and thickness in excess of ' 20 feet are common in the vicinity ! of Hiawatha and Mohrland. Ordi-' Ordi-' narily, however, the workable beds range between 6 and 12 .feet in thickness. The investigations have yielded a ! lavi:,e amount ofinformation as to the number, extent, and thickness of j the workable beds of coal; thoir lo-I lo-I cation with reference to surface features; their accessibility for mining, min-ing, and the quantity and charactei of the available water, timber, and other supplies needed in the coalmining coal-mining industry. One of the most valuable resuits of the work is the topographic map, by which the region re-gion may be studied and mining operations may be planned with a degree of acuracy not otherwise possible. The publication of all this matrial and the map will, afford the public a lamer amount of needful need-ful information concerning the field than lias hitherto been available. |