Show itah U S geological survey the discovery ol 01 light oil of good grade in southern utah and the knowledge that there are some large anticlines in that region has attract ed oil operators to that part of the state oil has been obtained from wells in two districts in utah one on san juan river some miles west of the town of bluff in san juan coun coup ty the other near virgin city in washington county little oil has been produced commercially in either of these districts however partly be cause of the great difficulties of transportation but mainly because of rather unfavorable geologic con dillons the possibility of obtaining oil in southern utah in the region between and somewhat north of the ta beill oil fields just mentioned was incesti gated during the summer of 1921 bv the united states geological survey department of the interior A parti under the direction of R C moore made a reconnaissance examination of much of kane and garfield coun ties and completed a detailed survey of the large structural dome in east ern garfield county known as circle cliffs cliff S the essential objects of the survey acre ere to locate structural tea features tures that indicate favorable es for prospecting for or oil to trace ac curatelo cura tely the geologic formations that are exposed in the region to ao examine the rocks for indications of oil and to make a study of the ture of the circle cliffs the surface rocks in south central and southeastern utah consist chiefly of sandstone and shale shaie that range in geologic aee age from pennsylvanian Pennsyl to early tertiary As this region Is al most a desert the rocks in it are e ex x posed nearly everywhere so that the surface geology and the structure may be determined readily the chief geologic units are the brilliant ly colored tertiary formations that compose the highest plateaus and that may be seen in numerous ex postures as in the scenically scent cally famous bryce canyon southeast ot of pan guita the cretaceous beds bed 5 which form orm plateau and the prominent tablelands table lands near the henry mountains the remarkable thick massive cross bedded jurassic sand stones that have been called by greg ory the navajo and wingate forma dons the chocolate colored and varl vart colored and sandstones sandstone of the triassic and permian and the thick beds of pennsylvanian lime stone the total thickness thic knees of the rocks ex posed in this region Is more than 18 feet the younger rocks appear to 0 o lie mainly in the northwestern part of the region la in the higher lands the older rocks mainly in the southeastern part in the canyons of colorado and san juan rivers and their tributaries rocks saturated with oil or con noticeable indications of it were found in parts of the Moen kop formation triassic in the circle cliffs and showings and seepages of oil bere rere found in the overlying conglomerate also triassic in the circle cliffs and along colo rado river above the mouth of the Bs calante oil Oll saturated Moen kop kopl beds have also been found in the san rafael swell the oil bearing for matlon mation of the san juan field Is old r than any rocks that appear at the surface in kane and garfield counties counti eq and Is therefore not exposed here but it should he lie within drilling depth beneath circle cliffs the circle cliffs form one of the largest and best defined anticlines in tou southern thern utah the cliffs which are composed of jurassic sandstone the wingate formation of gregory form w a almost impassable wall that sur rounds a lower elliptical area about 10 or 12 miles wide and 30 miles long the longer axis of this cliff walled inclosure trends north north west the rocks in the cliffs belong to the triassic and permian systems and the lowest formations kaibab limestone and coconino sandstone are found in canyons in the central part of the area the circle cliff cliffo consists of an asymmetrical anticline whose crest except at its north end marks the main divide between these streams that flow gow southwestward in fit to escalante river and those thoad that POW eastward into hall halls a creek the anticline Is really an tin especially high part of the great water pocket told fold which can be traced from a point beyond colorado niver on the couth to thousand lake mountain on OD he north a distance of about 80 miles the beds on the southwest elde side of the circle cliffs anticline havo a rather uniform dip which for many miles amounts to about feet to the mils mile in the plateau 23 miles distant the beds W A it 4 WW and the kaibab limestone Is there probably not less than 5 5 00 feet lower than in the central part of the circle cliffs cliff s the beds on the east side of the anticline have a very steep dip which averages about 30 but which Is in places place sas I 1 as much as 60 by this downward down warp the kaibab lime stone which has an elevation of 6 feet in the highest part of the told is carried to a depth of 2 feet below sea level in a distance of 5 miles the dip of the beds along the axis to the northwest and south east is only about 70 feet to the mile being thus much more gentle than the dip on either of the fanks the closure in this anticline is at least 1 feet at its south end the crest of the told fold is rather sharp and narrow but toward the north it be comes broader and less sharply de fined the detailed survey shows no minor domes or large terraces on the flanks danks of the main dome near the town of escalante there Is a much smaller anticline with a steeply dipping west limb and a gent ly dipping east limb the sandstone that has been called navajo by gregory is the surface formation over the central part of this anticline there are aiso in the region other minor structural features that have not yet been examined in detail A test well started by the ohio oil co near the crest of the circle cliffs cliffs anticline in january 1921 reached a depth of 3 feet in november 1921 when it was abandoned the drill pene grated about 1 feet of coconino and strata permian and penn syl and in the lower part of the well encountered thick limestone and sandstone that are probably equivalent to the goodridge forma tion pennsylvanian which contains the oil in the ban sall tuan oil field gold the failure to discover commercial accumulations of oil in these beds la in this large anticline was a severe dis appointment other test wells in the circle cliffs even if drilled deep er would probably not show different results but this well by no means condemns other anticlines in this region such as the geologically SIMI lar san ratael rafael swell farther north the record of the circle cliffs well Is of high geologic value as an aid to the study of the carboniferous stra ta in other parts of the south southwest w st As the circle cliffs well wai was a start ed cd at a horizon below the oil bearing sands in the moenkopi Moen kopi kopl and formations the lower parts of which aich crop out at the surface in circle cliffs wells drilled to test the possibility of obtaining oil I 1 in n corn com mercial quantity from these sands must be located on favorable Is anti dines clines where the moenkopi Moen kopi and shin arums formations are not exposed at the surface and are within able drilling depth in the anticline just east of the town of Ena escalante Ea calante lante the these se sands Us lie about 1700 1 to 2000 teet tee t below the surface oil bearing rocks occur in southern utah and prospecting in areas the structure is dav favorable arable will be coo cop tinted tint ed |