RMO-992
THE TEXAS COMPANY RESEARCH LABORATORIES
REPRODUCED FROM BEST AVAILABLE COpy
AERIAL RADIOMETRIC SURVEY LONG PARK AND CLUB MESA AREAS
MONTROSE COUNTY, COLORADO
By Evan Pancake.
Prepared for the U.S. Atomic Energy Commission Contract No. AT(30-1)-984
Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy. completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.
May 15, 1951 Bellaire, Texas
General Summary of Results Geology Mineralization Instrumentation Results
Club !1esa Area Long Park Area Conclusions
MAPS AND CROSS-SECTIONS Index ~~ap
lilap 1 - Club lilesa Area - Geology & Ore Occurrence Map 2 - Club Illes a Area - ARAS Survey - Work Map Map 3 - Club Mesa Area - ARAS Survey - Radiometric Map 4- - Long Park Area - Geology & Ore Occurrence Map 5 - Long Park Area - ARAS Survey - Work Map /ilap 6 - Long Park Area - ARAS Survey - Radiometric Section 1 - Club Mesa Area
Section 2 - Club Mesa Area Section 3 - Club /ilesa Area Section 4- - Club JlIesa Area Section 5 - Club Mesa Area Section 6 - Club Mesa Area
~r
cv(
!P-d-.
lilap Map 2 2 3 4 7 7 14-19 Page loa In Envelope In Envelope In Enve lope In Envelope In Envelope In Envelope In Envelope In Envelope In Envelope In Envelope In Envelope In EnvelopeRIBW
l
Q SALT!..AKJ:'..-CITY UTAH R 17 W Q GRANO JeT. O':NVER o COLORADOX !SEE DET-'/IL M/iP
o DURANGO R 16 W 2 \!l \51", '>l-~
I-""
...
I!'? ?ARK A~cA -1;. .... '"' .... ARAS 5URVC:YSMON7"ROSe .- Co., COi.O~AOO
th8 :::1i visi:Jl1. of Ra~·.r I,Iateria13 of the United States Atomic 1:Jnergy
Cf th~ four locations
Blandings> L-:Jng Pa.rk a.nd Club 1·~es,3.p represent carnotite producing districts of the Colorado Fla.tl~au 3.r9a~ !tTh::l,3 the fourth covers the
Ina.smuch as a cl:rilling and
o.d~l:~tional d.ata Ie::." -3v2.1uEttion purposes ie· c1lrrently in prGgress at
2·~andil1gp and field ma.pping and prospecting are continuing -s.t
1"'~ary3=-"",[,9.10] ,"'3. final evaluation 0f the survey Hork in these areas cannot. be
maj~ at this timso This report is therefore concerned chiefly with
the surveys in t!18 Club l'1esa and Long P~.rk areas ".".!here intensi \ffj completed..,
3UT-J:,':A2Y OF RE3ULT3 ~
The presence of e"v"en yery 1h"eakjl sub-corr.mercial carnotit.e
a.ppe3rs that. t-h:·:; intensity differentials attributable to va.riations iT, the
'.i·~holc:gy
of th'= reekse:~pOS2(~
'3.t surf3.ce ,'ire greater than J~h08G t~a~ xi.~ht
ews their origin to the carnotiteie903i~s
that hays)-
~
(.J,Y"'~
'.'.ll' -,g·!JI'o,,::r~-,.,.·,'.~.
l' -.-" -tht'- ,., .. ,.,\1'1')I
.bS'3!l dS781orr.:;d 'by tre reC~3nt diaP1o'..ld ... :.' . ~ '--. _~ _'~ = __
This ph'3Domena makes it difficult to uetermine whether or not radioactive anomal.i·3s C.re associated wit]:;
chest's Qurisd orebodieso
GEOLOGY:
~'·ThilG fOtlr p-::--incipal f0r~~~9.ti'Jns on the f~olorado Pla:tf~au are
s.ge)l tiE:' the Chi~le forn:ation
S8!'lt ;r[ork N5.3 ccnfinsd to the I·l~orr:'.scY.!. ror-n<2tion an,_~ the irr:media-:cl.y
'Jv~rlying D;;;.kGta sandstone of Up?e::.~ Cret,s.ceous a.ge"
On the basis of production to d3:te $ • the. 3alt \: .. 1a.sh member of
th::; =~.co~"'riso~1. forma.tion is the major host rock en the plateauo The ·':'3.1·t. ~-~"'8.sh,\l rarely exceeding a thickn,ss.3 of 100 :\?et $ lies at the
ba .. 56 of the I~1orrison, and consists of bro1i'm to red=brcl"'.vn s2.ndstones intGY'bedd.ed quite extensively 1--lith red to green=gray mudstones 0 ~'Jhile th,s ore-bearing sandstones show local continuitySl thsy de n.et rep::-~7.:"'"
gated red to green-gray mUdstones extensively interbedded with red to red-brown sandstone, minor amounts of limestone and occasional lenses of conglomeratic material.
The Upper Cretaceous Dakota sandstone, the Burro Canyon sand-stone of the U.S.G.S., is a gray-brown, resistant, cliff-forming member which caps many of the mesas.
From the above description, it is apparent there is no marked lithologic difference between the Salt Wash and the overlying Brushy Basin. The constituents are practically identical, the chief
difference being in the relative amounts of shale and sandstone present. This similarity is further heightened by a careful study of diamond drill hole core logs. Thus, there is no lithologie basis for an intensity differential between the Salt Wash and the overlying Brushy Basin member.
Map -I shows the distribution of the several rock types in the Club Mesa area, while Map
4
covers the rock distribution in the Long Park area.NINERALIZATION:
Although these deposits are normally referred to as carnotite deposits, the ore bearing minerals include, among others, carnotite,
tyuyamunite, corvusite, vanoxite and hewittite.
All of the uranium deposits contain five to ten times-as much vanadium as uranium. Small amounts of radium are also present. While the mills will accept ore containing as little as 001% U308' and some shipments assay several per cent, the bulk of the ore being mined falls in the 002% U30S to 0.4% U30S classo
-5-The ore occurs in tabular bodies which are frequently elon-gated, While these bodies lie generally parallel to the bedding, locally they are seen to cut across the bedding, For the purposes of the airborne radiometric work, they can be considered as always being parallel to the bedding,
For the most part, the orebodies are found in medium-grained, relatively clean, porous sandstones which appear to have been deposited in ancient stream channels, Careful mapping of these channelways
is of value in determining structural control, but little is known of the origin, or method of emplacement of the ores,
While the current, intensive diamond drilling programs being carried out by. the A,E,C, and the U,S,G,S, have found orebodies at depths of 300' to 400' below surface, the bulk of the present-day production comes from relatively shallow depOSits, with a depth of 100' representing, on the average, the limit,
Minor concentrations of uranium are known to exist in the Brushy Basin member, particularly in the vicinity of fossil plant and animal material, Some surface trenching has been done on at least one such concentration in the Club Mesa area, Further, in the vicinity of Uravan, Colorado, near the Club Mesa and Long Park areas, the United States Vanadium Company is currently mining an orebody which occurs in the Brushy Basin shale,
rlfap 1 shows the "mineralized areas" developed by the U ,S ,G ,S, diamond drilling program in the Club Mesa area, Also shown is the extent of most of the underground workings, Map
4
shows the "minera-lized areas" found by the U,S.G.S, diamond drilling program in the
i_""-
-:r-:;::::::::---Long Park area, Here again the extent of the underground workings is also shown, Also shown are the approximate outlines and loca-tions of several orebodies developed by the United states Vanadium Company in an extensive diamond drilling program.
It is advisable to consider the difference between a commer-cial orebody and a "mineralized area" as shown on Maps 1 and
4,
which were supplied by the A,E,C., inasmuch as the two terms are notsynonymous. In view of the strategic importance of uranium reserves, it is essential for the A.E,C. to have a record of all potential
reserves whether they are currently classed as ore or not. Thus, while the indicated "mineralized areas" normally contain material
that would show sufficient thickness and grade, disregarding depth, to be currently classed as ore, this does not mean that the entire outlined area is mineable, In every instance, i t includes drill holes lvhere megascopic carnotite was present in such minor amounts, as
determined by "eyeball assays", that it was not felt a chemical assay 'vTBS warranted. A comparable situation in the petroleum industry
would be the computing of reserves on "shows", While the "shows" .represent a definite amount of oil, they cannot be considered as
having any commercial value in the foreseeable future.
Another important point in connection with these mineralized areas is that the mineralization does not necessarily extend over the entire indicated area in the same plane, or in a continuous body. Thus, a given mineralized area may consist of a number of adjoining,
or overlapping, tabular mineralized zones, at varying depths below surface, or in different stratigraphic positions, whose overall out-line is indicated as a mineralized area.
-7-INSTRUMENTATION;
The airborne radiometric equipment, ARAS III, used for this work was d.esigned and built at the Company's Research Laboratory.
Detailed descriptions of the equipment may be found in earlier reports. For this survey the equipment was installed in a Bell heli-copter, l~odel 47-D-l, equipped with a 200 h,p. engine and skid-type landing gear.
RESULTS:
Club Mesa Area:
The Club Mesa area represents a wide range of conditions over which to carry out an experimental radiometric program, and of the three areas surveyed on the Plateau, it was un~oubtedly the best suited for this purpose. This portion of the survey covered an area of approximately 5.3 square miles with surface elevations ranging from 5300' to 6500', and required eighteen hours of flying time. Due to the radial flight line pattern necessitated by conditions at Club Mesa, this amount of flying did not cover as large an area as would have been possible if the flight lines had been paralleL Practically speaking, however, this was more ,than offset by the extremely long lines that were flown.
The Club Mine, seen near the right hand edge of Map 1, is one of the largest mines on the Plateau. In depth below surface, it varies from a rim outcrop at the east end, to over 100' at the western end. It is to be noted that all other mining operations lie around the periphyry of the mesa where they were found as rim out-crops.
The larger mineralized areas developed by the UoSoGoSo dia-mond drilling program can be seen to range in depth from 551 to 2661
0
As can be seen from the indicated positions of the many drill holes, the distribution of favorable environmental conditions has been
checked quite thoroughly 0
Map 2 shows the work map for the survey which is contoured with a 25 cis contour interval 0 While the work map has been submitted prior to this report, it was felt that its inclusion was warranted since it effectively represents. basic data, and should be re-examined 0
A brief examination of Map 2 makes it apparent that there is no standard, or uniform, intensity level over the area of the survey 0
From a standpoint of interpretation, such a condition would be idealo It would then merely be necessary to determine the magnitude of an anomaly that represented mineralization and the results would be fully interpreted 0
Lacking the uniform intensity level, it becomes necessary to examine the map on the basis of relative intensity differentials, bearing in mind that a 10% intensity change is significant from the instrumentation point of viewo This procedure was generally followed in the initial indication of anomalies when the map was first sub-mitted to the AoEoCo In the northern half of the map many small
intensity changes were not indicated as anomalies because it was felt that their small areal extent, and large number, was indicative
of something other than buried orebodies.
The eighteen areas originally listed as anomalous are shown on Map 2, and will be relisted in view of information that has become
-9-available since the survey was made.
CM-l Rim exposure and workings on the Jadl: Rabbit claimo
CP.fi-2 Rim exposure on the Chemist claim.
CItl-3, 4, 5 & 6 Apparently due to usi:ng dump rock from
mines for ballasting the main ore hauling read f;:oom the Long Park mines to the Uravanmillo
CM-i Rim exposure on the Telluride claim. GN-8 Ore stockpiles at the Uravan mill. CM-9 Club Mine.
OM-10 Rim exposure and workings on the Kaiser claimo
CM-ll U.S.V.Co. reports an orebody at a depth of 80', drilled from surface only, beneath this anomaly.
CM-12 Rim exposures and workings on the Rainy Day claim. CM-13, 14,
15
Rim exposures and workings in the Shamrockgroup of mines.
CM-16 Rim
.
exposure on the Mary claim.CM-17 Rim exposure and workings at the Raven mine. CM-18 Rim exposure and workings on the Buckshot claim. Referring back to anomaly CM-9, which was seen to be
aSSOCi-ated with the Club Mine, and comparing the shape of that portion of the anomaly showing a counting rate in excess of 1800 cis Id th the outline of the Club Mine, as shown on Map 1, it can be seen that there is some indication of correlation. Admittedly, the problem of con-tamination is a serious one, but it is not felt that concon-tamination is the only explanation of this anomaly. While there are dumps pre-sent, the major portion of the anomalous area does not have dump material on it. Unquestionably, some radioactive dust has settled in the area as a result of blasting operations, but the extent of this
contamination is difficult to determine.
In the area where the anomaly closely follows the orebody.1
"(hich ~o"tained relatively high-grade ore, the sl.,trfac€ I'ocks are comprised of the ore-zone type sandstone, and the orebody lies only twenty to !'orty feet below surface. Toward the west end of the ore-body, Where the anomaly ceases to follow the general location of the orebody,the surface rocks become shales with interbedded sandstone and the depth rapidly increases to about 100'. 'Thus, While it cam:.ct be proved, there is at least an indication that a portion of the
anomaly may be associated with the buried orebody itself rather than sole.ly 'with the dumps and other contamination resulting from the mining operations.
Information obtained from the (loS.G .. S. indicates that in the norc;narn half of the map, where the surface is also almost ",ntirely Br'ushy Basin, there are many smal.l mineralized areas, none of Which appear to warrant; further developmento Also in thls ar"ea, U .. S,,'J,Co,
has (kne some prospecting on mineralized occ ... .!rrences .in the Brushy
. Ba.sin"
Map 3, a radiometric map having a .l00 cis contour interval, was prepared to determine whether or not these small, sharp highs show2d any trends that might be significant. The selection of' a 100 ,,/s contour interval was made to smooth out the small, sharp, and possibly insignificant, changes but leave any broad trends that might be associated with themo
Away from the eighteen anomalies .listed ea1"1ier in the 1"&p·:;-:·C"
-11-of weak 'Carnotite mineralj~ation, or any conceivable broad pattern
of ancient chaYl-1lelways., It would therefore seem reasonable to assume
tha::· che sbarp intensity differentials noted are Q,ssociated only with haphazard variations in the lithology of the formations exposed
at surf'ace ~
Core logs on approximately 160 of the U,S"G.S, 's diamond drill holes were plotted in detail and sections made in an attempt
to recognize a usable correlation between the observed im:ensity variations and the presence of ore, depth of the ore-bearing type sandstone below surface., the thickness of the sandstone sectio!!, its overall favorabi1ity as a host rock, etc. As would be expected, the results of this work checked closely with the obseC'vations already made from a study of the radiometric map.
Six sections utilizing very simplified logs of 45 hol,es are included .in tne rep ore to show eypi::al results., The thickness· and overall favorabil.ity of the ore-bearing type sandstone were tak;;n from ehe U,S,G,S, logs, as was the assay data, The .i.ocatlons ot a.ll
assays ex,:eeding 0,1% U are plotted on the left si.de of th~, ho Ie, with the th.ickness and grade being shown below the sana.s'Cone s8c"G10,:'1o 'The extent of ore areas, or "mineralized areas", i.s shown along tne base of the sections. The locations of the several sections are shm'm on Map lo The intensities shown on the a:Lrborne radiometric profiles were taken from :Map 2,
Section 1 is an east-west section across an orebody dev21op~d
on tll,= Buckshot claim, While the nearby rim outcrop is mineraliz",c", the drill.ing 'indic:ates that the rim mineralizatiort doeS net extend
into the main orebody, At the left edge of the section is a pronounced
h.igh intensity area with the intensity rising as the mineral.iz'.sd r-im
outcrop is approached~ P~oceeding to the rignt across the
mineral-1zed area there appears to be an intensit-y rise 01' about 50
cis
over the ore which lies at a depth of about 75' 0 Further to the righ1; is'l 11811 defined anomaly whose peak is abou\; 125 cis above the intensity
rioted over ehe ore, This anomaly is reported GO lie O'Ter the slJrface e;,posure of a low-grade uranium concentration in the- Brushy Basin sna.l.'" on the Ace-in-the-Hole claim where the U oS, VoCo, has done some 1:T'€C!ching and pitting, A1;tention should be given to the ex-cent, of the ore a:rea, taken from Map 1, and the distribution of' the or'e as 3een in core assays, TYro holes included in the ore area~ 89 and 259, ilre lii3t"d as having only semi-favorable sand conditions and no mater-Ial from these holes was believed 01' Bufficien~ grade to warrant
8s::a"" A third hole, 91, shows material of a suitable grade, 0,,34% U,
but BO thin, Oal l ; that mining would not be feasibld~
Beetlon 2 1s a north-soutn section across ~he same ore body
,E'cn on Sc;ction L While this section crosses the first one through its bes';, ore section, it can be seen that neithe:7 the grades nor
the th.1clcTIf::8ses compare with t.hose seen on the f"i.rs'c 3ection 0 No
indication of a positive anomaly can be seen across the mineralized <lysa, rather the inte!lsi1;y is lower over the minerali.zed area, Thus, while one section across this mineralized area showed a small
inten-stty' rise over' the ml.neralizatioTIj a s~co:nd s2ction at r":1.ght B.T:.g.L~::
to "Cht,:: f'irs1; one showed a slight int.=rlsity drop over t.h.e mlner8..~ i.2J~',-.
-13-practlc.al use of the many small Im;ensity fluctuatIons noted,
Section 3 was included to show the intensity variations noted
over a barren sandstone section that is at or very near surfaceQ It
"'fas not felt that the 003" of 0013% U material seen at a depth of
84'
in hole 97 would have any appreciable effect on the airborne intensity profile, While an intensity differen1;ial exceeding 20% is seen, it does not coyorelate with the favorability or thickness of the sand sect:l.on, tne presence of shaly material covering the sandstone, or the mineralization in hole 97, It wou.ld appear that these inten-sity fluctuations are related solely to lithologic variations in the rocks exposed at surface, or possibly surface exposures of minor uranium concentrations in the Brushy Basin shale,Section 4 lies over a deep, and essentially barren, sandstone zone tJilith only one hole, 247, cutting a small mineralized zone, No dis1:ing'Qishable anomaly can be Been associa'ted·with the mineraliza-tr'Ol'l., although the intensity fluctuations along this section represent a differential of' 50%"
Section 5 was included to illustrate two poin-cso The first can be seen at hole 31 near the le:rt hand edge of the sec1;io!l, Here a shallow sands'Cone section outcrops as it crossea a ra'Tine and it can be seen that no significant anomaly is assooiated wi;:;h the sand-stone outorops as distinguished from the overlying and unde!'lying shaly materiaL Continuing to the right, two very pronounced high intensity peaks show the effects of contamination, These peaks lie in anomaly CM-4 and are associated with the main ore hauling road that has been ballasted with dump material from the mineso The
smaller of the two peaks represents where the section is adjacent to the road, while the larger one is where the section line crosses this road.
Section 6 shows a sandstone zone whose depth below surface decreases more or less gradually from over two hundred feet until it outcrops, One hole,
35,
encountered minor amounts of mineralization at a depth of 245' 9 bu'c ,no intensity differential is seen thatcorre-lates with it. While there is an overall intensity '["ise to the rig.ht on the section as the sandstone decreases in depth" it 1s not felt that this is truly correlative with the sandstone depth, :From the left hand edge of the section to about its mid-poin'c, bole
37,
the intensity remains very uniform while the depth decreases from 220'to 120', Just to the right of hole 37 the intensity rides sharply and, with 75
cis
to 100cis
fluctuations" continues at this higher level to the right hand edge of the sectio'n as the depth of the sand-stone decreases from 120 f to 0', Thu.s, while a first glance at thesection '..,ould indicate a correlat.ion" a more carefu.l examinat:Lon shows that there is no baSis for such a conclusiOn..
Long Park Area:
The Long Park area, which lies several miles south of the Club Mesa area, is not toe well suited for an experimental program such as was being carried O'Ilt, For the' most part.. the areas where the mineralization either outcrops or occurs at shallow depths are badly contaminated by large dumps, Away from these areas the
topography rises while the Salt Wash dips relatively steeply down the east limb of the Paradox anticline, Thus, over most of the area
-15-flown, the main productive horizon lies at depths greater than 200', and in portlonR of the area the depth exceeds 400', The Long Park survey covered an area of approximately 3,4 square miles with surface ele'lations ranging from 6200' to 6700', and required 19~ hours of flying time, The slower rate of coverage, as compared to Club Mesa, resulted from the necessity of flying relatively short survey lines and drastically limiting the helicopter's gasoline supply to enable safe takeoffs under existing operating conditions,
Map 4, supplied by the A,E,C" shows the rock type distribu-tion, most of the mined areas in and immediately adjacent to the survey area, U,S,G,S, diamond drill holes and the mineralized areas developed by this drilling,
Since the data upon • .,hieh the .size, shape and grade of the indicated mineralized areas was assemb1ed, the U,S,G,S, has completed additional holes at Long Park, Lacking the final are reserve figures,
the ILS ,Q ,S, stated that while the additional data might extend the mineralized areas somewnat, and also slightly affect their grade and thickness, it would not affect the order of magnitude or general relationships indicated on Map
4,
and that the information shown on l'iJap 4- should be sat;isfactory for the purposes of this report 0While this diamond drilling shows the presence of mineraliza-tion in the deep-lying are horizons, it is of no value in determining
thi:? nature of the Bru.shy Basin section inasmuch as coring was ncr.;
started until the hole was either in or very near the Salt 1,~asho
Abo;ve this point a solid, non-coring bit was lolsed, and the cCltting:" were blown from the hole with compressed air, Al though gammc ray _.'lgS
were run on each hole with the U.S.G.S's BARNABY equipment, the Brushy Basin section was not logged. Therefore, no information is
available concerning the lithology or possible uranium concen-crations in the Brushy Basin shale in these diamond drill holes.
The larger of these mineralized areas can be seen to vary in depth from 250' to 385', so that the minimum depth here approximates - the maximum depth, 266', at Club Mesa. Particular attention should
be given to not only the depths, but also the thickness and grade of this materiaL For example, -the shallowest of the larger mineralized areas is seen at about the center of the map. The data adjacent to this area shows that in the ten foot interval from 250' to 260', there are bands of mineralization averaging 0.31 thick with an
average grade of 0.01% U308 . It will be recalled that the lowest grade material currently accepted by the mills is 0.1% U308" I t
should be pointed out that this country, Sweden and Russia have literally millions of tons of bituminous shales that will assay at
least 0.01% U30S' I f it be felt that an isolated case has been chosen, a quick examination of the other intervals, thicknesses and grades
shown on Map
4
will convince even the most skeptical person as to the general quality of the reserves shown.Also shown on Map
4
are several orebodies developed by the U,S.V,Co. 's diamond drilling program. While no work other than drilling had been done at the time of the survey, mining operations have since been initiated. Although tonnage, thickness and grade figures are not available on these orebodies, i t must be realized that they are such that U.S.V.Co. expects them to be profitable-17-operations or they would not have undertaken actual minl.ng operati{.ms 0
Map 5 is thE: 'Work map for the Long Park su:r-vey and is C8D.'-'
toured '"ith a 25 cis contour intervaL Here again, as at Clu.b ,iisa;). .• it can be seen that there .is no uniform intensity lev.'ll over the area of the surve~y. At the same time .• it is apparent t.hat southeast of anomalies LP-2 and LP-], and the general area between anomalies LP-l2 and LP-15, the intens.ity gradients are not as steep as those
:in the remainder of the area, and those seen at Club iVlesa. This is probably largely due to the fact that these two areas are covered principally <rith alluvial material Which, due to the weathering and :oectepos1tlon associated with its origin, usually shows fairly cons is-tent intensities. Tn theSe areas an attempt was made to indicate
thOSe intensity changes that were felT.: to be of signH'lcant magni-tude from the instrumentation point of view 0 In o-che:r portions of the area, the sharp intensity differentials resemble those seen on po.rtions of Club Mesa 0
It would be well at this time to re-exam1.neche 25 anomalous areas shown on Map
5
at the time of its completion.LP-l Surface exposures and workings on the Dan Patch claim. LP-2, 3 Mine dump.
Lp·-4 Limited drilling on the west half of the anomaly shows ·some mineralization.
LP-5 Lies 200' west of orebody 120' deep developed by U.S.V. diamond drilling.
LP-6 No correlation wi-cn available information, LP-7 Surface ·"rork on the Sunny Jim claim.
LP-9 Mine dump and road ballasted with dump material, LP-IO, 11, 12 Mine dump,
No correlation with available information, LP-17 Lies over a portion of major mineralized area shown
by U,S,G,S, drilling. LP-18, 19, 20, 21, 22
tiOD.
No correlation with available
informa-LP-23 Surface exposures on Dan Patch claim.
No correlation with available information.
An examination of these anomalies, other than those associated with dumps and known exposures, show that they generally fall into two types. The more numerous type, such as LP-4, show an intensity differential of sufficient magnitude to be valid, but the change is of a gradual nature. The other type is seen in LP-19, 20 and 22, with LP-22 representing a large number of them. Here the intensity change
~~
is generally very sharp and of a greater magnitude than in the other
//~
type.
In connection with this second type, it is interesting to note that they occur only in areas where the surface rocks are the Brushy Basin shale, and that their strike is essentially parallel to the hillside on which the Brushy Basin outcrops, This leads to the hypothesis that they may correlate with small, lenticular- areas of weak uranium mineralization, as have been noted on Club Mesa. This is further substantiated by the f.act that the U.S,G.S. reports just such occurrences in the Long Park area. Time was not available to allow this to be checked by detailed surface radiometric work with the RASP portable unit.
-19-Anoms.ly LP-17 warrants further consideration in vie'i'l of' the
fact tha.t j in addition to covering an a.ppreciably large area and
shcitli:;:lg a.n intensity differential of more than 60;'0, it is not
asso-c:i,::tted v.rith any kno~'m sllrface exposur-eso While in all probability
it i'epreSe:1ts a concentration in the Brushy Basin at or very near
surfaCE Sl it· does lie over a recently drilled extension of the major
mineralized area developed in Long Park by the IT.S.G.S. drilling prog:-'am, A .detailed surface radiometric survey of this area with a
,suit..:ibly sensitive instrument, such as the Company!s RASP unit,
shoul.u provide very interesting data.
'·~2.p 6 is a radiof.1stric map having a 100 cis contour interval.
similar t·o r"J:ap 3 of the Club i'.T6sa area" ~\To additional signii"ica.nt
t:'sr:.ds can be seen by the use of this method of presenting the data.
In vie~'l of the extreme depth of t.he ore horizon and the lack
of information covering the upper portion of the holes. no detailed cross sections .'3.re included t·o cover the work in the Long Park area,
From a study of the results of the surveys in the Club ],lesa a.nd Long Park areas, it is quite apparent that rim outcrops of even weakly mineralized zones are readily detectable in routine ARAS
survey operations" Such a fact should make the use of airborne radio-metric surveys extremely valuable in the detailed prospecting of the thousands of miles of rims in the Colorado Plateau area.
Weak concentrations of uranium. associated in large part with fossil plant and animal material. in the Brushy Basin shale
section also appear to be detectable. While by and· large, these
thE:.t "Gl:.is type of occu:;:-"rence must not be oVerlooked 8":3 a possible
s()urc.e of uranium¢ The. a.rea3 of Brushy Basin outcrcp t..:,hat could be
pr0sp~cted in t,his manner a.re quite extensivev
There is at least an indication that recognizable anomalies are seeD over orebodies lying at shallow depths. In the areas sur-vey-sd suitable conditions for the :;?recise determination of the. extent. c.:f this probable cOY'relation were not available", In any event, it 2.3 r·~o.3()na.ble -:0 expect that such a cor-relatio!1S1 if actually preSent.~
w~u:d be quite dependent upon such factors as depth of the
ore-bod}T beloltl surf2ce p the type of r-ock covering the orebod.y 9 as well 3.3 ..:...1._ .,
!..J.i.!.'::;;
'The pr'3sent ~.1o:,k has .3hot·~·n that large int.ensity variations
(.~~~:..s"':, OV;~y· both Brushy Basin and Salt ~"!ash outc;rops in areas ~Hher8
dia.rr.cnd drilling has fai18c.. to indic,3t.::; the: pr8sence of ur-3.nium
r.r:iner,s.lization in those horizons "t;1n.eY'G i t tvould !!or::nal':y be e:;cpectedo
-r,·~h:.::.'~
:.t.
is impossible from the available d.8.ta to d!:=ter-:nine ;,-..rhether3ition of the rocks exposed at surface, and/or minor conc2nt~2tions
of u:~;;;.niu:n haphazardly distributed in theSe rocksj the most important
-21-Gei v.3.ble t·hat by capillary Betic!:. gC'Jund t~Taters. ~'\rould carry ,soluble
ur'G.:"2ium salts fro:!"1 a buried orebody to surface '\.vhere they would be
d0~~Eited by aith~r eva?oratic~ or precipitationo Su6h a deposit
CC1.l1d then serve as a 3urface 30urce of radiation !",I=lated to the
bu!':'ed 0rebody which could be expected to ShOTfi up in a radiometric
SUl""itey ~ either surface or airborne !I a.s a positi VB anomaly 0 itIhile
at bsst ,3u~h 3. sur'face depo3it would be very 10\1[ grade.9 and thus
:--es.ul-c in a small intensity different.ia.l~ it 'would obvious:'y be
re-lat&d to the amount of ground \vater present, the depth of the deposit
b-2lo"'tl sur-fac8:v and the amount of soluble uranium salts presents)
turn, ,,[ould be related to the tonnage and grade of the
Inasmuch as the intensity differentials noted over barren
B:-'ushy Basin and Salt \'lash outcrops are apparently much larger than
i:.hose associated with the upv,ard migration of soluble urani.um salts from buried orebodies in this area, it is doubtful if it; would be
po.ssible to util::'ze surface or airso.rne l adiomatric. surveys in the
3e21'"h for buried deposits in these formations,
Further experimental \V'ork ~'iould be necessa.ry osfcre thiE
c:mclusion could be extended to the buried deposits in 'Che JVloenkope,
3hin.3.rump and Chinle formations 0
2P~bj
Bellaire, 7exas
5=15-51
