Radioactivity at the Copper Creek Copper Lode Prospect, V Eagle

Radioactivity at the Copper Creek Copper Lode Prospect, V Eagle

I Radioactivity at the Copper Creek 1 Copper Lode Prospect, V Eagle District, East-Central Alaska Trace Elements ln'Vestigations Report 195 / UNITED STATES DEPARTMENT OF.THE INTERIOR 1 L\. GEOLOGICAL SURVEY ") \l\ 'I Fi ~ c~oo) T~'1 ~ OfFJCIAL USE ONLY ~.' lq5 Geology ·""'' Mineralogy Thl$ document .COA$;b;ts of 10 page$o Serie~ A UN-ITED SlATES DEPARTMENT ,O.FTHE INTERIOR / \A .S • GEOLOGICAL SURVEY ---·~ ~,.~ ..~ ~ RADJOACTJVITY AT THE COPPER CREEK ,COPPER LODE P,RQSPECT1 EAGLE DISTRICT 1 EAST~ENTRAL ALASKA* By Helmuth WedoJ~ l1..-;,.,d Gene · . Tolbert) ftj),$"- September 1952 Trace Elements Jnve~.tigc;~tions Repod 195 This preliminary _report is dls;tribut.ed without edltorial and technlca.l rev.lew {Qr ,conformity with official standard$ and nomenclature. lt is not fo~r pub­ llc inspection or qu9tatlon" *This report concerns wowk done on behalf of the Divi:sJon of Raw Materials .of the U. S. Atomic Energy CommtS5Jon OFF.I.CIAL USE ONLY OFF~ClAL USE ONLY 2 US'GS: ""' TEl Report 195 GEOLOGY ·~ MJN.ERALOGY .Db3tdbutlo.n ~Sede$ A) No. of eopies AmeJr.ican Cy_onamid Company 1 Waiedown , ., ., ~ " .• "" ., .., .., ·. ~ • ] Argonne National Labor.at.oey • .• · Q · " " .o ,., " ... "" ,. " o _., o <> .• . "' " .1 Atomic Energy Comml~ion, W~hington o o .., ,., .o • ..... o o _., ..._ ., 2 Carbide and Carbon Chemicals Company I v~;12 Area 0 o_ 0 " ·o 0 1 Colorado Raw Material$\ OJfice (F o ·H o MacPherson) o ...... ., " , 1 Oiv.i$ion of Raw Materials; Grand Junction .. · ~ ......0 • • • • 1 DivJ$ton .of Raw Mat~rJals ., Gr.ant$ -o .. .. • o o . ... • 1 Dtvh>Jon of Raw Mateda-lsJ Denver • ., . .. .•• .., .. • .. .. 1 D i vi% ion -ef .Raw Mated als1 Hot Springs Q • , o o • .• .. • 1 Divlsjon of .Raw Material$-, New York .~ ., ~- • " o 6 DivisJon of Row Matedal$, :Salt Lake City o •.• 1 Di.vbJQn of .Raw Materials, Rlchfleld A ... • • <> o. 1 Divbion of Raw Mate.riaJs,~ Butte o • ... .• . •.• .• •• - ~ •. ·!lc •• .. .. .. ... o 1 Dlvi~lon of Raw Material~ 1 . Washington o .• • • • .. 8 - Dow Chemical .Company, Pittsburg p • • , .o o. .. ... .. 1 Jechni.cal Information Service, Oak JUdge ., ..... .. o ... o .• 6 Battelle tv\emoJJ".ialln$titute1 Columbus' .. .. o • o o. 1 Tenne~e Valley Authority, WU$0n ()am , .. .. .. ... ... o ., ... ... •• • 1 U. S. Geologic;:(]l Su. wvey~ Mineral Depo~ihi Btaru:h,· Washington ... ., .......... ..... o o • 1 Geochemi~twy _and Petrology Btan.ch, Wclshington • "'· .. 4>. o "' 1 Geoph.ysiC$ B.r:an.cb, WO$hington . ~ . " ........ " o " " .. .... , ~ - 1 Al~kan Geology 1\raAc:h,~ Washington o , ...... "*·. .. • ... ... .. 10 Te:1r.r .. Dept.. Mines 1 Juneau (P. H ~ Hold$worth, Jr ..;) . .. 1 Ten o . Dept .. Mlne~, Ketchika~ -(A... E, Glover) o ... .. ., .. ... ,.. .. 1 Ten. DepL Mine$, AAehorage (P. 0. Sandvik) ... .... .... o .. 1 Terw ... Dept o _ .Mlnes, College (L... l .. Patton) o ... ,.. 1 Ten .. Dept ... Mines, Nome (D ... Jones) •. .•. -o .. ~· .. .. • .. o 1 G .. 0 .. G.ate%, San Froru:h~.co .. ..... " . .o .. "' .• .. .. •• 1 E.. A. Youngberg 1 Juneau .... .o . .... ., ..... ....... - ~ . ... ... •• • .. .• 1 _R.., M .• Chapman, FalrbQnks <0 .. ., " ..... " ... "" .. _, ~ - ~ . ... .. .... .· ~ 1 V. E. Me.Kelvey 1 _ WO$.hington . , ... ..... .. - ~ _., .._ . .. .... ._ •• .o- 1 _L .. R.. Page, Denver."; o .. ... ., .. , ... ""' -o .. o .• · ·4 ..... ............. .. 1 .It, P~ Fi$cher , _Gran -d Junction .• , .. o .. • • ...... .o ........ .. .. 1 A .. E ~ WeiMeAborn, Spokan.e •. ., .... ......... - ~ ..... .. o . .. ·" .. .. .... o 1 TEPCO -' · Wa~hi.ngton • • .. ., ~ .. ........ "0 .... ., .... • • • .. .. ... .. .. .. 5 {inel.uding master) OF.FJC!AL USE ONLY OFFlClAL USE ONLY 3 CONTENTS •- • · ••o ~ ._ ,. .. ... .. .,_ .•.. 4 lntroduetion 4 .... .,. ~ Geology ••. ••, .. .. .. ..• Cl' · • - ~ • · - .,... 7 Radioactivity $tud.ies 7 A,_ ·.. .. • .. • • Con . clu~Jons "' . ,. .. ... ... ., ·~ ._ 10 .Refe.ren .Ce$-.. cjted • .• .. ·'!· .. • • .. • • • . .. ... '"· .... ... " .• • • • .• .. ... .. 4 10 TABLE Table .1 .. Data on selected $0Mples from the Copper Creek copper lode ,pros.pect, Eagle dl$trict, eCI$t-eentral AICJlka. • .. 9· I.LLUST.RATJ.ON flg~re .1.. Skete~ map of the Eagle di-strict, Alaska • •. .. ..... .. ·.• ~ 5 OFFlC.IAL USE ONlY OJFIC1AL USE ONLY 4 RAO.!OACTlVlT'l AT THE COPPER CREEK COPPER LODE PROSPECT, EAGLE DtSTRLCT;~ _ EASI:-CENTRAL ALAS.KA By Helmuth VVedo,w, Jt .. and Gene E ... Tolbert ABSTRACT lnvestlgcatloq of radioactivity ,QRomalles .a:t the Coppe.r Creek .copper lode pr.O$pect 1 Eagl~ dl$trlct, eCJ$t,..,·eentr.aJ Aluska 1 _ eluting 1949 dbcJo~d that the radioactivity i$ .asso.clated wllh coppeJ m.ineralizadon in highly metamorph~d SedimentaJny -rocks. The~e 1ocks .are a. roof pendant in the Meso:zoie ••Charley -Rjve:J• batholi.th. The fQdloactivity ~.s probably all due to urani.um qsociated wlth bornite an.d mctlachite e JNJRODUCTlON The Copper .Creek coppE~r lode prospect b located iA t.he sout-hwe$_tern pcu:t of the Eagl~ di'striet, eCQto-centroJ Alaska.1_ Qbout 60 mile5 west .of the t.own neG¥ of Eagle 1 which lSc the in lternotlonaJ boundary (fig~ l) . .The protpect i.s on the right bank of Copper Creelk ,about 6 miles above the creek•$ confluence with the. Charley R1-ver.," The Copper Creek prospect ha' n.ever been reported in G.eologi.eaJ Sur:vey literature although know.l.eclge of Jt ts widespread. among pros.pectors. in interior AICJSka.. It was .staked and p_artiaJJy developed by the Hudson. btothe.rs in the ecn:ly 19001.5, but since then has cha1rtged hands several times. The owner .of the cJcd m in 1'949, Howard Sparb of F . airbanks:~ restsked the prospect ln 1946, pdmat:ily on _the <)fFIClAL USE ONL. Y UNITED STATES TRACE ELEMENTS INVESTIGATIONS DEPARTMENT OF THE INTERIOR REPORT 195 GEOLOGICAL SURVEY FIGURE I 22"f2 1 ~ \ \ ~ «"') ~ ~ \ '' "' I / / ~ c I I Q:' {-I J w /~ .... ~ .... U) \ /\ / \ ~ / ... _ ~ c1 I a. / - Q\S 'TR\ I 0 \__\ 0 ( // fQRi'<t-'ILE. 0 \ (!) ) ( ( / \ EXPLANATION I ~- 3725-L Sample from lode prospect ( -\ \ ( 0- 3688 Stream concentrate '\__ /'-- ' --- - '\._,...-\ .... ) "-1 -- 10 0 10 20 30 Miles 1 I 1410 EAGLE DISTRICT, ALASKA OFF~CIAL USE ONLY po$£lbU ity that the gold, l$1lve ~ r 1 lead., and tung$ten content in addition to the copper might wall;rant furthew exploration Q The workings at the Coppe.r Creek pr.~pect con~h;t of an adlt in a eLiff'-$t.Jrface showing of copper ore.. The portal i$ 10 to 15 .feet above the level o.f Coppe.r Creek and the working~ extend 114 feet underground~ The ore showing$ cx::cur only in <Jbout the first 40 feet of the adi,t. Lack of understanding of a complex strueture apparently c.au$ed the earlie.r pro$pectors to wander off the t)rend of the ore.,..,bearing zone with the res:ult that the hut 60 feet of the adlt isenHrely in e~ntially barren rock.._ The radiometric examination of the Copper Creek prospect was made 0$ a ~ide trip in con.nection with othe.r radioactivity studie$ in the adi<:~cent part of the Fotty.- mile dis.twict (Wedow and Tolbert, in preparation)~ Traruspo~rtation to the pro~pect' w.as by a Sikorsky Model H5G helicopter furnished by Detachment B, Tenth Re~cue Squ~dron, U .• S. Air Jorce, based at Ladd Field, Fairbanks. The examination was made on August 17, 1949~ The author.$ were accompanied by Geor.g_e 0 ~ Gates of the Geological Suwvey and Howard Sparks, owner of the pll'O$.pect. The statement below on the geologie setting .of the prospect ha! been t.aken mainly from field notes by Gate'$. Thi~ -work was done on behalf of the Division of Raw Materials of the U. $., Atomi(: Ener:gy Commiss-ion. OFFlCaAL USE ONLY I OFFICIAL USE 'ONLY 7 GEOLOGY The bedrock at the Copper Creek Olode prospe~t, pre~lou~ ly mapped in reconnal5Sance as Meso~oic(?) g J ~anite (Prindle, 1913, pl. 2; Jv\ertie, 1937, pL. 1), consi·sts of highly metamorphosed sedimentary rocks,. These _. rocks are apparently 11 part of a small (sever.al ~' mi~ TOC)f pendant in the 11 Charley River batholith and ae,ted as .a host .for the depos-ition of the metallic minerals found in the p!l"ospect. Ten~ative !dentlficaticins . :show lime:-•silicate rock and amphibolite as the' two main lithologi~ types at the prospect: . ' The bufk of th.e metallic. minerals is in the Urne:~i licate r.ock, mainly along a conta.et wlth the amphibolite, although minor amounts,of the metal'lic minerals are dls.seminated through both rock types but in· dlmminis~ing amounts away from 'the contact. ChalcopyrHe, malachlte and azurite are the chief metallic minerals at the prospect.. Minor amounts of ga.lena ' ' are present and tr.aces of gold, s.il-ver and tungsten have been .reported in assay~. RADIOACTIVITY STUDIES The radioactivity of the rocks at the Copper Creek prospect was meas~red wi.th Q commercial model of a portable SL.Jrvey meter modified to accept both the standard 6-in. beta""'9amrna probe and a probe consi.sting of six 1..- by 14-i.n. copper-walled gamma tubes connected in paroll~el • The variation .ln radioactivity ln the adit, as measured with the large gomma probe, is .summarized as .follows: OFFICIAL. USE ONLY OFFICIAL USE ONLY 8 Distance (ft) into adlt Radioactivity from portal (dlv b lon~ on 2,.0 scale) Rock type 0-2 12 Li.me :~il icate ~rock end amphibolite ... 2 .-18 10 Do. 1.8-32 8 Amphibolite 32-.40 10 Lime-'""'$ ilicat:e Jr:ock.Q 4 o ~ - 44 16-18 Lime~i Iicote ro.ck with iron ~tained fracture zone$., 44- 48 12 Lime~i Iicate Jr.ock o . 48 ... 54 10 Doo 54~ - 114 8 Do. Te~ting with the 6-in. beta-gamma probe lndicated th.at the radioactivity ai. the 11 portal" anomaly ts JocaUz.ed around eertain mineral groupin.gs in the ore zone •. At the ''4044" anomaly the mdloactivity _appears to be confined to iron~~tai .

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    11 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us