A structural examination of the Telfer gold-copper deposit and surrounding region, northwest Western Australia: the role of polyphase orogenic deformation in ore-deposit development and implications for exploration

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(1)ResearchOnline@JCU. This file is part of the following reference:. Hewson, Simon Andrew John (1996) A structural examination of the Telfer gold-copper deposit and surrounding region, northwest Western Australia: the role of polyphase orogenic deformation in ore-deposit development and implications for exploration. PhD thesis, James Cook University.. Access to this file is available from:. http://eprints.jcu.edu.au/27718/ If you believe that this work constitutes a copyright infringement, please contact [email protected] and quote http://eprints.jcu.edu.au/27718/.

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(3) I. ~. ..---.. --.-;. '-ur--' _ _. .---.... .~.. "". ~. / \ I .\.I. \. •. -.".. .~.. \. •. \. \~. I. '-""-'1\. ~~~~:1'.~Geology Gravl," Ob.cured. 0/ ./.. \. \. /. \. \.. , ,. l'yW, '\. GEOLOGY MOSTLY COVERED. INTERPRETED FROM REGIONAl.. MAGNETIC DATA. '. \ GeoIO\lY unknown S~~~~!~t$/ Intrusives (Pon) d. \. '\ .--'-"'". .~. ....L---.---.. /. / /. I PyP. Pym. \ "__ UI\d;fht.ntlotn Country Roc. o...IJIII9 ~;... \ RoofP.._. "-. \. '\. \. \ I. /. I. I I. /. I. /. I. \. \. I \. \. \. I. \. p,p I I. \. \ I. I. \. I. J. I / I ! I. ~. I. "'-............... '-'-.. 1 II 1. LITHOLOGY. 'r;;;;. Psnnlan Pt_ Formation t..:::..J. (ftuv\ogI$CIaIs). CD ....lYequartz_1IfI. ,. PyP. GIl dolorita_. \. I~ I Syn- &{und~. " " , - granitoids Trlo",l. bOM. IPyI( IKollran. romlltlo.. \. \. \. I.,wl WIItd QuortzIto FormaIIon I pyP IP._gRla FormaIIon IPyT ITelfer formaIIon IPyM I"aIU Q!. \. ,. \. TN \. \. _formation. \. I!!!J _IFormaIIon. I. I. ,. ~ Si_1ndotont. 6i;il C1rbonaltlcalc-arenlle. J Eii!!. \. Leuc_ "gntIu1c" rock. ~ GameI,ebltt. o. Geological boUndaries. 2. 6. 4. SoGle 1'100 000. - - Known «>uIctopl - - - Interpreted (utIlItlng~. Folding 1D2 ..... -mIIfIIdl. I • AntIcUn. (mIJoi). Geophysical boUndariea _. • .l!l... MagnetIc !hIgIt{_Tl>Io_ on........,l aub cropphlgtgntOUlWn?). _ . ...L Gravl\y«.15mg11O;_on"""'*Y) --.,.JmL. Magntllc L"'-nt. t. S¥I1CRnI (mIJotI. l. AnIIformal (mlno~. f. SynformaI(.-q. ...... I~. ·f. 1(. AnIIfonn Varue-. faulting. Btddlng ~. sttflctIIIIp'mollllnd). -~::. Trend. -. 8. - - FlulUr.... =. Younging. ft.. Nonnll. MlSca\laneous. Cleavage. - - PublicfOld,unaoalldj - - Track. 82 (1IrIkt/dIjIl. •. S41_1pl. Tellfer lRegiollll - SoUd. ~I. Geology HlIllte1rpll'etll.tiollll. lMIAIP. ~. Fyi. MAPPED and COMPILED: Simon Hewson (JClJ). S5~. DRAWN: Jane Breale~. DATE: March, 1996. Undlff. Foliation (_PI. B'. A 1401'1... Allticll ... C I. --. "". •. t. ...--------------"-.". Math.... JAME'SCOOK UNIVERSITY UBRARY. •. ,. • t. I. t. ". Oom.', ~~ ~~~r-\l~~~~~;:'~-l~~~j;~~~~~~~~~~~~~~~~~~~;;~~ I t t t. itt i t. I. I. ,, ,. -$'" I. t. Y". H. •. .. -. !. I. t. +. -. •. -. 10. 20. o. •. •. PyT. t. I. -. *. +-. t. ---lI4t1 I / /'\../ ;.-. ---- .. !. > t. •. + !. ,. I. eyl. ... •• t. unknown BattmMf. I. t_. LongSeedon 30. •. -". 10. 30. C'.

(4) TELfEROOME. ~-'----. 7S9S000mN $porotIC Outc:nPt OfCOG1W ........ .......,.nlt./Sytnn. (I.... RtII.f). -. P-01.04:I...... -- ------- ---;.,:--. ..... ....... --. SIron. Fl • .,.", "'DII.. ., Wlfll ......... , 10._0100. Of Ouetrtdt.. ...... - :: -. f-. -. -t -:.. -. ""----. ..... ---,-..j......./'"". ""':!I--- - -. ---- ----I'f~f2. ~. ..'. '-. -. '-. LITHOLOGY rp;;-l Permian Pat.aon Formation L..:..:.J (IIuvloglacials). [!] maaaIVe quartz veining. I!lI dolerite dlkea. TN. (.). ~ III. I eyW I Miki QuartzIte Formation. !!iII PlintaPunta Fonnallon lHIJ-I--- G!J Tal. Fiiiiiiatlon-. JI. tyM. I Malu Quart%ite Fonnatlon. ~ ltd.. Fonnalion. o. 0.,. I. '.8. Qeologlcil Boundaries -_.!Inown - - ·Inferred. -+- 't. • direction (dip u.-.-J). ---. • trend • younging direction !-w). {:;/. I~----=:::::::>. ---. -synformal. .... • minor folde (1ren!fIpIungo). 0-". - antIl)Jlna! vergence. ~. ~. antlfonnal. JAMES COOK UNIVERSITY. -102lnteraeclion lineation. LIBRARY. Faultin9 -S1 -82. ·S3 -S4. +. ·85. • undlff.lw_1. Veining (tIriktIdfp) _ _ - prominent extension veining. - - ·tractl__nt _ _1 • •• - "1gI1-angie reverse. Structural Geology of the 0' Callaghans Corridor. _!II- . tl'llMQlrrent 1_ _ l1IdIcaIIII) ~~. • local allearlng. MlscellaneoliS • tracks (unsealed). •. • minerai prospedldeposlt. fI!. • mine. line tlllckneeal. propoI1fonaI to _Ie 01101118 and f8IIlta. Solid nnt: poeItlon known Broken 8nt: position Inletred. ~I. -- ---. MAfF>. ~~. MAPPED and COMPilED: Simon Hewson (JCU) DATE: March, 1996. SCALE: _1:50,000.

(5) SUMMARY TABLE OF THE DEFORMATION HISTORY IN THE TELFER REGION· (For use with Sections A, C, D & E) S. Event. Upright open to tight and isoclinal. Teetollie R. NW -SE trending fold axes. NE-SW directed tectonic. Recumbent monoclinal folding; locally. S 1 : 15,30' -7 SW,W. South-west directed sub-. overturned NE (short) limbs; coarsely. F~. horizontal thrusting/. spaced axial plane cleavage (S I), which. (both strongly refolded by. vertical shortening;. exhibits a top-to SW shear sense.. D2). locally extensional. Upright open to tight NW-SE trending. S2 : 70,90' -7 SW, SSW. NE-SW directed bulk. regional folds, with a penetrative axial. F~. : 0,50' -7 NW,SE. inhomogeneous tectonic. plane cleavage (S2).. L~. : steep pitch on S2. shortening (230-050'). most. D2. Orientation. Ie. now recumbent.. : 2,15' -7 NW,N. Recumbent asymmetric monoclinal. 02. NE directed sub-horizomal. folding and discrete sub-horizontal. S)': 10,20' -7 315,340'. crenulations. Most examples are meso-. F~. ,F; :. thrusting/differential movement and vertical. NNE. shortening. Gravity-. scale; rare axial plane cleavage (S3)'. 0,5' -7 NNW,. induced collapse post-D2. Upright cross folding of D2 folds with a. S4 : 70,85'-7 255,. rare coarsely spaced axial plane crenulation cleavage (S4); generally. F~. meso-scale folding.. 265. inhomogeneolls tectonic. : 40,45' (variable) -7. shortening (255-075'). 320'. Upright kink folds, cross folds with associated weak coarsely spaced. (b) Mainly brittle stmctures including veining, dolerite dikes, fault and kink folds.. 04. S5: 70,85' -} 290,300'. WNW-ESE directed. (inc!. kink fold axial. inhomogeneous tectonic. plane). cleavage (cf. Chin et al, 1982).. ENCLOSURE 1. WSW-ENE directed. shortening (290-110'). S5: 75,85' -7 350, 355'. NNW-SSE / N-S directed. (inc!. kink axial plane). tectonic compression. (j]. = 345-165" to N-S..

(6) Yeneena Group. Broadhurst Fm.. o. Coolbro Fm. Basement Gneisses (undiff. Rudall Complex). 7540000mN. ~. o~. \5. ~. ~. o. %0-. ~.. ~/. Numerous closely spaced anticlinal and synclinal folds commonly overturned to the SW. o I. 7520000mN. Antiform. 10km I. Synform Fault Location. ENCLOSURE 2. Geology of the Rudall Metamorphic Complex and Lower Yeneena Group, Paterson Province, and field locations (For use with Section B).

(7) TELFER DOME. o. z. =>w 0:E 010. N. ;:0. 2kms. <Co::: o:::w I-LL. Open Cut 11000mE operatio~Midd Vale Reef. en-l. LL W. 01-. ZW. ~~. I- Z => -. ~en. o:::LL I-W. W -0:::. en. o. o. Ow. i:~ 0..-1. <C<C 0:::0::: (!)W. -z. 1--. <C:E 0::: I-. en. TELFER FORMATION. -. MALU QUARTZITE FORMATION ISO ELL FORMATION. -. Camp Sandstone Member (20-25m) Outer Siltstone Member (SOO-S40m) - E-Reefs Rim Sandstone Member (24-26m) Upper Vale Siltstone (14m) Median Sandstone Member (38-40m) Middle Vale Siltstone Member (S-9m) - MVR Footwall Sandstone Member (20-22m) Lower Vale Siltstone (2-5m). -. 500 - 700m - M-Reefs. >1000m - I-Reefs. ENCLOSURE~.

(8) Structural Geology of the Telfer Dome/Mine. Folds (02 unless annotated). t. Antiformal Synformal. f. -16000mN. Faults. .. ... •. Normal Reverse/thrust. •. Transcurrent Bedding (strike/dip). "<.. Cleavage (strike/dip) S1. <v. S2. \,. S3 Jointing (prominent). "". o. 11mn. I. I. LITHOLOGY. -10000mN. t\·/:·::-J Camj£andstone z. o. Ix:,1 OuterSiltstone. ~0:::. RirrSandstone. o LL... 0:::. l-:-:-:-:-:-j Medial£andstone. -I. B. UJ LL... UJ. BOOOmN /. 8(XX)mE. :NCLOSURE4. r-. 1CXIDnE. o. MiddleValeSiitstone FootwalBandstone.

(9) 7,590,OOOmN. o,. ,. 10km. 390,OOOmE. I. I1lJ Dolerite Dikes lI!1 Granitoids. -~-. __-I-______. Antiform (trend/plunge). (-:-:-:-:1 Kaliranu Formation. _...-----.,I----~. Synform (trend/plunge). Q.. e D D. ::::s. C). C'CS. Wilki Quartzite Formation. C. G) G). Telfer Formation. cG). >-. Malu Quartzite Formation t·:::·:·;·;:·) Isdell Formation. ENCLOSURES. Fault. Punta·Punta Formation. -. -. Magnetic Lineament (Dolerite Dike). Sl1. • Prospect/Deposit. Seismic section lines (unpub. data) •. Regional granitoid.

(10) Average trend of 52 cleavage ~ ~. CA. CA. Average trend 52 cleavage. A..:::f. 1. Max. ellipse (SO) dip. 1. DH. H S2. SW. CA. CA. Orientation of unoriented drill core utilising cleavage-bedding relationships (i) south-west limb, bedding does not bisect 81 & 82 cleavages, same vergence, inclined bedding dips towards the 8W (ii) central limb, bedding is subhorizontal, 82 direction can be identified by viewing core so that 81 verges right (NE), looking NW at core. (iii) north-east limb, bedding bisects 81 & 82 cleavages, inclined bedding dips towards the NE (iv) overturned bedding on north-east limb, bedding is steep in core, 82 cleavage inclined towards the 8W. Average trend of S2 cleavage. CA. CA. Average trend Of 52 cleavage. A...5. S0" Max. ellipse ~ (50) dip. S1 DH. DH. CA. S2. ~ CA. NE. (iii).

(11) fP{~~~O~~~l. fP{ ®©©)[1iI fill lID ~ ~ ~ ~}[1iI ©®. ~J{[Pl(OfP{~ 1~(0)~. (0) rr @\9J ® fill ~ ~{ [p) ~ @ rr lID U @ rlil. FOLDS. SHEARS. Left-stepping faults, and consequent jogs, bends and steps. SHEARS. Pressure shadows around granites. Gaping of internal strata. Identify orientations using D4 instantaneous strain ellipse. Left-stepping faults. Auriferous shears along the margins of dolerite dikes in s complexes. Veining. D3; preferential gaping of NE limb. D4; preferential reactivation of NW & SE corners. STOCKWORKS. LOCALISED GAPING. Restricted to alteration halos. Vein geometries identified from D4 instantaneous strain elli. D3; gaping on vertically inclined strata structures. Identify subsurface granites. D4; gaping at contacts between granite and foliated country-rock.

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