Show lei lot I 1 file IN IN IN if IN 11 is lei im IN lot 1 W lei lot W Is I 1 W 1401 IN im IN I 1 of lei IN I 1 III WIN IN IN 11 IN let lot im IN 1 1101 lei IN lei IN im I 1 GEOLOGY OF MT BALDY BELT i by J F gibbs i is I 1 of is I 1 lei I 1 le lei lei 1694 1 ell lei lei lot W I 1 is 1101 to I 1 lei is ael WI lei lei lei lei lei 1 I 1 I lei lei W lei WI 1101 lei lei marysvale Marys vale division barring complex conditions caused by unusual faulting along the foothills on the east and back into the mountains a distance of from three to four miles the geology of the marysvale Marys vale division is easily read it is clearly evident that at some depth the entire range is with a broken and faulted substructure of quartzite and that it may be credited to the devonian age at the close of the lower carboniferous a gentle upward movement occurred and the area under discussion rose abo above the surface of the ocean where it remained during the enormous lapse of time that intervened between the closing centuries of the lower carboniferous and well along towards the close of the Tertia ray age when an almost worldwide world wide change of level occurred along the east side of and parallel with a g corp h r M M V y 01 ip 1 ak 6 Y I 1 ap tel I 1 nt e s t 0 n e e CA V jmj ro A quartzite v k alk C 0 L tp cli kolej A f A pm ha h A WP VOL AN iv 0 me ak I 1 lill U W W ow or it t 1 U 00 vv q T I 1 W L I 1 it 3 4 gr 0 F q N R A ph VIE fit C W k t P jo lyall lyl ll topographical MAP ELT 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 the preponderance of evidence is that the area now represented by the mt baldy range and its northern prolongation the mountains between millard and sevier counties was under the ocean during the devonian age hundreds perhaps thousands of feet of sandstone was deposited the succeeding lower carboniferous period covered the sands sandstone tono with a thick bod bed of limestone what is now now known as the mt baldy range and its northern prolongation the range the earths crust was fissured from the surface down to the region of molten I 1 rock the fissuring was succeeded by faulting and an idea of the tremendous displacement may be formed from the statement that deer tra trail 11 peak the highest elevation of quartzite is fully feet higher than the valley while the eastern section of the quartzite is buried beneath hundreds of feet of basalt and other eruptive material the displacement extended northerly a distance of nearly miles in sevier valley the sandstone so 60 conspicuous along the vast east side of the Pa livant mountains is anthe on the east side of the valley buried under hun deeds perhaps thousands of feet oferell of arun rull tion material this stupendous displacement is known as the sevier fault in the vicinity of marysvale Marys vale a great fis fig sure on the east paralleled the sevier fault and is now marked by a fringe of ba basaltic S alti foothills and volcanic activity must have continued over a long period after coni comparative para quiet reigned along the mt baldy range the evidences of which are found in the mixture of volcanic inic bombs and debris in a belt of oolite bullion canyon represents a lateral fault extending westerly from the sevier fault 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 cottonwood the topographical and cross section maps to which the readers attention is invited will serve to illustrate the profound northerly and southerly faulting of the basic formation of the mt baldy range the teachings of geology prove that the S j if VON AWI aljy MAP VA 1 7 dynamical history of the region to the west and southwest of marysvale Marys vale is as follows A large area occupied 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 uj 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 partially healed wo wounds ands were opened and new fissures formed in the overlying arup tive mass and great dykes of highly mineralized erali zed porphyry now mark the location and direction of many of those ancient rents through the weight of the su superimposed super p er imposed mass of eruptive material the associated heat and presence of strong solutions timis the underlying sandstone was altered changed alto to the now familiar quartzite there are several localities where the sandstone escaped those agencies and retains its old time characteristics and insensibly merges into quartzite as it nears the igneous formations mat ions the brief period of comparative quiet which succeeded the previous disturbances was broken by another uplift of the rallies range band and along the central portion exten extending ding from gold mountain south a distance of some ten miles a great fissure was formed from the surface down to the region of liquid fire the mighty force which split the northern portion of the mt baldy range also formed lateral fissures extending easterly erly and westerly from the great central 1 1 rent those fissures became lines of easement 1 for the vast mass of mag I 1 ma seeking egress and from molten depths the hot gaseous mud flowed upward and formed great dykes of phonolite which to e J V X Y phonolite Phon olit e Y J limestone cross see U 91 ra e arteue tilte wis Loo kinjo N 0 t crotton can day cheerily clinks under the feet of an occasional lonal prospector while the eruption of the phonolite marks the last throes of nature ture in the mt baldy region subsequent local fissuring assuring of the phonolite occurred land and in connection with other fissures already 1 fo formed amed became channels for the upward and lateral flow of gold and silver bearing solutions v I 1 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 linued over a long period after the wide spread eruptive activity had ceased the readers attention is now directed inore lore 0 particularly to the topographical and cross section maps while we investigate the economical results of dynamical forces just described i 1 to avoid confusion the great porphyry dykes only have been mapped and the veins along the trend of those dykes ar are e prominently drawn the cross section shows the deer trail mine occupying a blanket contact which dips to the north at about eight or ten degrees and is hidden by overlying debris in that locality the owners have blocked about tons of ore having an average value of tenor ten or twelve dollars per ton about feet distant to the south many carloads of ore were shipped and which netted the owners several hundred dollars per ton in lead silver and gold it Is believed that the contact derived its filling by solutions from the north where eruption rock is in evidence and probably associated with a lateral f fault ault the high grade ore to the 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 i is situated the lucky boy t that h at years ago yielded a large quantity of high grade mercurial ore the origin of which is an 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 limestone the ore was almost pure silver and with no visible reason for its presence in a locality where conditions are seemingly so unfavorable the first great porphyry dyke that traverses almost the entire district occurs about three miles west f from rom the mouth of cottonwood canyons canyon and occupies the great northerly and southerly fault line along this dyke is situated the nelson a vein of gold bearing quartz that projects above the ground like a great wall the branch vein is strong and its permanency has been proven it yields s silver I 1 iver I 1 ana gold the standard is a monster ledge and yields lead silver and gold almost exclusively in sulphide conditions on the north end of the dyke Is situated the copper belt to the west of the crystal mine and trending northerly is a great dyke of porphyry that after traversing the marysvale Marys vale section bends northwesterly into the gold mountain district along this dyke is situated the bradburn group a producer of high grade ore and now has exposed a 15 foot vein that averages 20 per ton ane property is being worked by pittsburg peo pie ale and ought to develop into a bonanza down on the bullion creek side the dyke forms the hanging wall of the webster a monster vein with great chutes of gale galena na and crys crystallized tali zed lead carrying gold and silver space will not permit of any description of the horse heaven and other fine properties along the great webster dyke another monster dyke dike cuts the country from the east side of mt delano over into bullion canyon there is a large number of fine properties on the dyke and ous to it A study of the maps will convince anyone at all familiar with the relation between geological conditions and the occurrence of veins and values that the country to the west of marysvale Marys vale presents one of the most inviting fields for int intelligent elligant ell igent investment to be found in the united states the B W and H DI division it would not only be an injustice to the B W and H section of mt baldy but to readers of the mining review to omit a brief description of one of the richest and most recently opened mineral sections in the state from the northern extremity of the mt baldy range a vast belt of eruptive material reaches out to the east and merges into the northerly and southerly mountains to the east of marysvale Marys vale the entire belt is highly mineralized as everyone knows who has passed through sevier canyon in which the rio grande western railway is built that remarkable gorge was broken through the eruptive belt by a reopening of the sevier fault about five miles northwesterly and barely over the line in sevier county is a northeasterly and southwesterly dyke or belt of birdseye birds eye porphyry A mile and a half west of the river several parallel fissures were opened in the birdseye birds eye and were filled with continuous ore bodies that have thus far paid for every dollars worth of development in texture and general appearance pe arance the ore is identical with samples from the famous tonopah district the skeleton map given herewith will serve to illustrate the topography and the relation of the B W and H fissures to the sevier fault the veins are paralleled by a highly dyke or vein 50 to 76 75 feet wide and carrying average values of about 4 per ton in gold on the surface those fissures are hardly distinguishable from ordinary cracks in the rock A few feet in depth and those fissures fissure s open into ore streaks from two to ten inches thick at about feet in depth where one of the fissures has been opened by a foot tunnel the vein shows up from 18 to 36 inches of ore that yields per ton in gold and silver the permanency perm anancy and richness of the ore has passed the realm of doubt and there here t are aia many who from geological conditions belleve believe that the locality is destined to equal in productiveness any district in the state |