Show W GEOLOGY OU A 1 T OF 0 F MT mf BALDY n DA GOLD BELT B BY J F GIBBS 1 i I 1 S marysvale Marys vale division ia t t darring barring complex conditions caused by A 4 unusual al faulting along the foothills on the y 15 S 1 i east and back into the mountains a dis fance danee of f from rom three to four miles the geo h logy of the marysvale Marys valo vale division is easily read I 1 0 y 1 it Is a clearly evident that at some depth itt the ho entire range is with a bjolsen v r and faulted substructure of quartzite and that it may be credited to tile the devonian a age e A small area to the north of the gold run canyon road presents some contradictory evidence the overlying limestone contains fossils credited to an earlier age than the devonian its presence is an enigma and cannot be discussed at this time y the preponderance pie of evidence is that the area now represented by the mt baldy r range and its northern prolongation the mountains between millard and sevier coun counties tiep was under tinder the ocean during the devonian age hundreds perhaps y thousands of feet of sandstone was depos cited the succeeding lower carboniferous y period covered the sandstone san astone with a thick T i bed of limestone TA k at the close of 0 the lower carboniferous X gentle upward movement occurred and exly eX lJ tile the area under discussion rose above the i y surface of the ocean where it remained dur ay ing PS the enormous lapse of time that inter between tile the closing centuries of the aci at lower oscr carboniferous and well along towards t i tile the close of the Tertia ray age when an all 1 most worldwide world wide change of level occurred IS 1 A long S the east cast side of and parallel with tf what is now known as the mt baldy range tu and its northern prolongation the fi J range the earths crust was fissured from IA X V tile the surface down to tile them region of molten y rock fia tile the fissuring was succeeded by faulting M and an idea of the tremendous displacement t V tt may be formed formea from the statement that 1 l deer trail peak tile the highest elevation of df sy quartzite is fully feet higher than the fv valley while tile the eastern section of tho the ma tzUe ta is buiten beneath hundreds of feet 11 of basalt and other eruptive material the i displacement extended northerly a distance of nearly early miles in sevier valley the V k sandstone so conspicuous along the east mif side of the Pa livant mountains is on the tat east cast side of the valley buried under hun t perhaps thousands of 1 feet of arup tion m material ater lal this stupendous dous displacement m nt is known as the sevier fault up in the vicinity of marysvale Marys vale a great fissure on the east paralleled the sevier fault and is now marked ly by a fringe of b basaltic salt ac foothills and volcanic c activity must have continued over a long period after comparative quiet reigned along the mt B baldy aldy range the evidences of which are found in the mixture of volcanic bombs and debris in a belt of oolite bullion canyon represents a lateral fault extending westerly from the sevier f fault ault the apex of the divide between two mile and bullion is quartzite and is fully 1500 feet higher than the quartzite to the north of bullion creek another area of stupendous displacement exists along the cottonwood fault where deer trail peak rises fully 1000 feet above the quartzite on the ridge to the south of Cotto cottonwood nood the topographical and cross section maps to which the readers attention is invited will serve to illustrate the profound nort northerly hely r and southerly faulting 11 1 1 of the basic formation of the mt baldy range the teachings of geology prove that the avi 04 J 11 corp h ry 4 0 1 l naia r YV Na iW W h I 1 ber h V 4 i I 1 0 V C R M ga a nest one 0 iyo is cad 91 y LL ct r d 4 y v ae y p A P 11 L tt C CY tr Y v tsal tto 1 ai T zit w i jbf a v I 1 JL PS ml na is i W V cl L 7 7 P 4 A s sv m ak it U 1 I R ell M K K J 11 A CY e kay I 1 fa N V kf V R 1 N U a k LII 1 1 I 1 s L s e 1 i al aw A j N Z 0 iw or 4 g ay vat S asa s n 5 faliti V 64 J A p rif rt xv q V J A r nt Rs vilgo I 1 al 1161 1 I 1 P WA 1 i lia Y topographical flap 11 A P rit baldy 1 ir RZ A L D ELT marus dynamic dynamical cal history story of the region to tile the west and southwest of marysvale Marys vale is as foll follows aws A large area mccu occupied p led by sandstone with a limestone capping because of the shrinkage of the earths molten interior or because of the accumulation of gases seeking lines of easement the crust was fissured and broken into enormous fragments or blocks some of the great masses maintained their position but the larger portion settled down into the yielding mass of underlying igneous matter from those yawning fissures enormous masses of and birdseye birds eye porphyry oozed up from the earths melted interior and formed mountain masses thousands of feet deep again the unstable crust quivered with intense seismic forces the old and but p partially arti ally healed wounds were opened and new fissures formed in the overlying eruptive mass and great reat dykes 0 of highly mineralized erali zed porphyry now mark the location and direction of many of those ancient rents through the wet weight lit odthe superimposed super imposed mass of eruptive material the associated head prez prenco enco of strong colw ons thet the f ab sac i underlying sandstone was altered changed to the now far familiar dillar quartzite there are arc several sev eral localities loc a gitles where the sandstone escaped those agencies and retains its old time characteristics and insensibly merges into quartzite quart q uart zito zite as it nears the igneous formations mat ions the brief period of comparative quiet which succeeded tho the previous disturbances was broken by another uplift of the range and along the central portion poi tion extending from gold mountain south a distance of some ten miles a great fissure was formed from the surface down to tile the region of liquid fire the mighty force which split the northern portion of the mt baldy range also formed lateral fissures extending easterly and westerly from the great central rent those fissures became lines of casement for tile the vast mass of magma seeking egress and from froin molten depths the hot gaseous mud flowed upward and formed great dykes of phonolite lRe which today cheerily clinks under tinder the feet of an occasional prospector while the eruption of the phonolite pho nolito marks the last throes of nature e I 1 in the mt alt baldy reo region gion subsequent local ns fissuring suring of the phonolite occurred and in connection with other fissures already formed became channels for the upward and lateral flow of gold and salv silver er bearing solutions extinct craters fields of dark colored tra chite ridges of volcanic breccia dykes and chimneys of obsidian in the phonolite prove that local volcanic forces were continued over a long period after the widespread eruptive activity had ceased the readers attention is now directed more particularly to the topographical and cross section maps while we investigate the economical results of dynamical forces just described to avoid confusion the great porphyry dykes only h have ave been mapped and the veins along the trend of those dykes are prominently drawn the cross section shows the deer trail occupying a blanket contact which di tl th e aarah at about abac it eighnor eight or ten dei grees and uti d is hidden hid de n LY uy delares delar ls iff that locality the owners have bl blocked 0 C red about tons of ore having an average value of ten or twelve dollars per ton about feet distant to the south many carl carloads of ore were shipped and which netted the owners several hundred dollars per ton in lead fe silver and gold it is believed that 1 thas e intact derived its filling by solutions from ern alnor ear ghere ere eruption rock is in evidence and a l aty ass d with a lateral fault the high grade or ore e to 0 ija qt south doubtless owed its origin to a secondary movement of solutions which passed through the large body of ore leached beached it and transferred the concentrates to the higher portion of the contact higher up on the deer trail escarpment is situ situated abed the lucky boy that years ago yielded a largo quantity of lit high 3 h grade mercurial ore the origin of which C h isan unsolved problem still higher on the mountain side is situated the once famous pluto like the lucky boy it proved to be a surface deposit in ill limestone the ore was almost pure sll sil iier and with no visible reason for its presence in a locality where conditions ara arc seemingly so unfavorable the first great porphyry dyke that traverses almost the entire district occurs about three miles west from the mouth of cottonwood canyon and occupies the great northerly and southerly fault line alo along ng this dyke is situated the nelson a vein of gold ol bearing quartz that projects above the ground like a great 3 wall the branch vein is strong and its per man manoney cilcy has been proven ii it yields silver ana gold the standard is a monster ledge arid yields lead silver and goli gold almost ecla in sulphide conditions on the north end and of the dyke is situated the copper belt to the west of tile crystal mine and trending northerly is a great dyl dyke e of adi if phyra that after traversing the Marys val section bonds northwesterly into tile the gob mountain district alon this dyke Is sl U 2111 QUI oi A ev yi A high grade ore and now has exposed a 15 toot foot vein that averages 20 per ton the w property is being worked by pittsburg people and ought to develop into a bonanza down dawn on the bullion creek side the dyke forms the hanging wall of the webster a monster vein with great chutes of galena and crystallized lead carrying gold and i N t za wt 4 0 ka 1 balmyr cro w hafi y y Z M c 1111 I 1 h 1 i ys finest one H R clydl et e clait rt z yf L t e q A fr 0 efrat nt cou 0 C w 04 CJ 11 of LZ silver space will not permit of any description of the corso heaven and other fine properties along the great webster dyke another monster dyke cuts the country from the east side of mt alt delano over into aullion canyon there is a large number of fine properties on the dyke and contiguous to it A study of the maps will convince anyone at all familiar with the relation between geological conditions and tile the occurrence of veins and values that the country to the west wast of marysvale Marys vale presents oneff the most inviting fields for intelligent investment to be found in the united states GOLD MOUNTAIN DIVI DIVISION SION J alighting from the train at Sevier station 4 on ther the R G W R R the observant traveler to ao gold mountain will notice that the rugged rind and broken toot foothills hills are composed of basaltic material As one proceeds westward and enters clear creek canyon he will note Z 4 rz aid az Z Z r IL A 14 fe a T T 54 q 4 V 41 ilu na F r ral T rib ott Z L 13 c J 4 a 0 Y AAL C f ph 4 1 t el 1 V eel CA ka k R V b t Z 1 I GOL D IDI VIStON T A L D Y N 1 N CE R A L B E L T 1 the fact that the sow gorge has ha been ploughed sloughed hed deep in a bed of basalt which as robinsons ranch Is approached becomes more columnar in its structure the bed extends westerly fro from m sevier sta station tiona a distance of some esome 7 fourteen miles where rhyolite becomes becom esthe the ean i int ry rock lop kand and forms the apex of the i mac ng e the earlier of the mt baldy mineral belt are described in the division of the subject and to ha reader rapo ore d the basalt extends some three to four miles north of the canyon and is alsoto und ed ad by rhyolite and other eruptive rocks the upward climb from robinsons to gold mountain is among basaltic buttes weathered to fantastic shapes and highly colored or discolored through tile the action of strong solutions tho the basalt extends to within a mile orso or so of gold mountain and to the stran stranger er is a subject of curiosity interest and study 1 in n some localizes loca lites the basalt caps the rhyolite but in a general way jt it merges so gradually into Int athe the rhyolite that no line oade of mar kation is visible contemporary with avith the great sevier fault and extending westerly thor efrom 7 we the earths crust was profoundly broken or 01 fissured along a line now r represented ep resented by clear creek canyon and intersected and crossed by the great greab fracture which once extended from southwest of marysvale Marys vale along tile present apex of the range range through 61 gold old mountain arid onward to the north into the range those principal fissures including innumerable parallel fissures were openings for the upward flow of rhy rhyolite blite and kindred eruptive material prior to the complete solidifying of the rhyolite the clear creek fracture reopened and basaltic material was forced up through the partially congealed thy rhyolite olite and which explains the blending of bf the line of contact beginning a short d distance is fance north of the if a annie achie laurie lauric see topographical madva belt of I birdseye porphyry 1 I extends southerly a distance of a mile or two and ds disappears ap under the mode more recent rocks to the east cast of the annie laurie an enormous belt comes in from mt belknap and forms the divide between kirn him berly basin and the head of deer creek and abid is also so far as exposure is conce rend rond the east local boundary of the birdseye this Is peculiar porphyry with its dark 11 1 al fp aart pot ocl r uth ith alm ost efte t specks and spots extends westerly over the tiptop divide and lowa towards F fisli ish creek the dip of the magnificent annio annie laurio laurie vein or veins is towards the west and on that side at a distance of perhaps or feet from tile the droppings crop pings is a dyke of porphyry entirely distinct from tho the country variety the locality where the dyke is most prominently exposed Js ie on bowtho the hillside to the southwest of the blua bauo bird tunnel she tiptop divide is tile the apex of a jarge dyko dyke of porphyry which occupies a northerly and southerly fissure or line of faulting tho rho great sevier lodge ledge with its marvelous mai wealth traverses this dyke on a southerly strike and upon which the tiptop i and other bonanza claims are situated S southwesterly from the tiptop the formation changes the birdseye bird porphyry on the surface at least gives way to rhyolite and tra chite tc faulting is more conspicuous and explosive volcanic Tol canic activity more in evidence within this area and well in towards grand old baldy is situated the fine property of the trappers pride the geology of the loch locality lity is given by a gentleman intimately associated with the mines and is as follows the country rode is altered which has undergone a series ol of faill ting and thereby tending to make it per pen to tile the action of mineralizing mineral izing sold eions the faults so far as developments lia have ve determined are parallel with the veins thus far no lateral faulting has lias been encountered to the east and southeast of the trappers pers pride und and directly north of mt belknap Is s a great held field of phonolite nearly all of bilich is highly stained with iron oxide the locality yields beautiful specimens mene of neph nephritic litle phonolite several undeveloped but most promising veins are opened with short tunnels the decomposed filling pans gold in milling quantities in a general way the gold mountain 1 faults dykes and veins trend towards that stupendous uplift represented by baldy and belknap Dol knap and incidentally proves that the majority of bf the lodes are tr true fissures ns gash veins occupying as they do shrinkage cracks in the cooled eruptive rock lack the regularity of strike so conspicuous in the vein system of the major portion of the mt alt baldy region |