New till geochemical targets for potential porphyry Cu±Mo...
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BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres 61 - 84 (105) 85 - 92 (32) 93 - 126 (36) 127 - 152 (9) 153 - 170 (6) 171 - 452 (4) Cr (ppm) <63 µm INAA Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres 10 - 29 (98) 30 - 35 (38) 36 - 43 (38) 44 - 47 (8) 48 - 56 (6) 57 - 101 (4) Ni (ppm) <63 µm Aqua Regia, ICP-ES Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres 3.8 - 15.2 (96) 15.3 - 16.9 (41) 17.0 - 18.7 (37) 18.8 - 20.2 (8) 20.3 - 20.9 (6) 21.0 - 32.0 (4) As (ppm) <63 µm INAA Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres -2.0 - 5.0 (143) 5.1 - 9.0 (33) 9.1 - 11.0 (7) 11.1 - 18.2 (5) 18.3 - 31.0 (4) Au (ppb) <63 µm INAA Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres -1.0 - 1.0 (179) 1.1 - 2.0 (5) 2.1 - 5.9 (4) 6.0 - 29.0 (4) Mo (ppm) <63 µm Aqua Regia, ICP-ES Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres 9.00 - 41.0 (103) 41.1 - 46.0 (36) 46.1 - 59.7 (33) 59.8 - 70.9 (10) 71.0 - 117 (6) 118 - 522 (4) Cu (ppm) <63 µm Aqua Regia, ICP-ES Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres BL FORT OWL EEva EO lmJHSH EEva PJCS PTrCRgs uTrTv PTrCSvb PTrCTum PnTrCTus uTrTvb EMJSPd DTrT DTrT EEva LTrBgb EEva DPAgs uTrTva uTrJSs LTrBum lmJHvf PTrCRgs DTrTma EEvl MJSLM MJSPsy EGo LTrJTpT LTrgd LTrgd LTrJTpT EGo uTrTvl DPAls DPAsf EEvf uTrTv EEva EMJSPd EEvl EEva Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek Geology (Cui et al., 2015) Paleogene EE Nechako Plateau Group - Endako Formation va: andesitic volcanic rocks vl: coarse volcaniclastic and pyroclastic volcanic rocks vf: rhyolite, felsic volcanic rocks EO Nechako Plateau Group - Ootsa Lake Formation rhyolite, felsic volcanic rocks va: andesitic volcanic rocks EGo Goosly plutonic suite granodioritic intrusive rocks; granite, alkali feldspar granite intrusive rocks Jurassic lmJHvf Hazelton Group coarse volcaniclastic and pyroclastic volcanic rocks lmJHSH Hazelton Group - Saddle Hill Formation undivided volcanic rocks MJSPsy Spike Peak intrusive suite syenitic to monzonitic intrusive rocks MJSLM Endako Batholith - Stag Lake plutonic suite - McKnab phase quartz dioritic intrusive rocks EMJSPd Spike Peak intrusive suite dioritic intrusive rocks Triassic to Jurassic uTrJSs Sitlika assemblage - clastic unit undivided sedimentary rocks LTrJTpT Topley intrusive suite - Tochcha Lake stock dioritic intrusive rocks Triassic uTrT Takla Group v: undivided volcanic rocks va: andesitic volcanic rocks vb: basaltic volcanic rocks vl: coarse volcaniclastic and pyroclastic volcanic rocks LTrgd unnamed granodioritic intrusive rocks LTrB Permian to Jurassic PJCS Cache Creek complex - Sowchea succession mudstone, siltstone, shale fine clastic sedimentary rocks Permian to Triassic PnTrCTus Cache Creek complex - Trembleur ultramafite unit serpentinite ultramafic rocks PTrCTum Cache Creek complex - Trembleur ultramafite unit ultramafic rocks PTrCSvb Cache Creek complex - Sowchea succession basaltic volcanic rocks PTrCRgs Cache Creek complex - Rubyrock igneous complex greenstone, greenschist metamorphic rocks Carboniferous to Permian DPA Asitka Group gs: greenstone, greenschist metamorphic rocks ls: limestone, marble, calcareous rocks Devonian to Triassic DTrT Taltapin metamorphic complex lower amphibolite/kyanite grade metamorphic rocks ma: limestone, marble, calcareous sedimentary rocks MINFILE Showing Fault Road Butterfield Lake intrusive complex gb: gabbroic to dioritic intrusive rocks um: ultramafic rocks CG CG YA AX AX NAc ST WR WR AX AX AX NAp QN QN QN NAc m NAp CA SM SM SM SM SM SM YT YT CC CD CD BR BR MT MT MT MT PR PR CR CR CK CK BR BR BR BR CC NAb NAb CA OK YT Atlin Nelson Stewart Terrace Quesnel Kelowna Smithers Victoria Kamloops Vancouver Penticton Cranbrook Dease Lake Revelstoke Fort Nelson Port Alberni Dawson Creek Williams Lake Prince Rupert Prince George Fort St. John Atlin Nelson Stewart Terrace Quesnel Kelowna Smithers Victoria Kamloops Vancouver Penticton Cranbrook Dease Lake Revelstoke Fort Nelson Port Alberni Dawson Creek Williams Lake Prince Rupert Prince George Fort St. John 116°W 116°W 124°W 124°W 132°W 132°W 58°N 58°N 54°N 54°N 50°N 50°N 0 100 200 km Copyright © 2011 British Columbia Geological Survey B R I T I S H C O L U M B I A G E O L O G I C A L S U R V E Y Coast plutonic complex Pacific Ocean Alaska Yukon NWT BC Alberta USA eastern limit of Cordilleran deformation Chugach Cache Creek Wrangellia Alexander Yukon-Tanana Yakutat Stikinia Quesnellia Coast complex Pacic Rim North America - platform Methow Kootenay Cadwallader Chilliwack Crescent Bridge River Harrison Lake Slide Mountain AX WR CG YA YT OK Okanagan ST QN HA CD CK MT PR CR BR SM CC m NAb NAp North America - craton & cover NAc Cassiar CA Outboard Insular Intermontane Ancestral North America TERRANES Location of study area. Geology from Colpron and Nelson (2011) Study Area 1 2 1 2 3 1 2 1 2 1 2 1 2 1 2 1 2 1 2 BL FORT OWL 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres Ice-Flow Indicators Field Observations (Levson et al., 1999) Striation (direction known) Remote-sensing Crag-and-tail (direction known) Drumlin (direction known) Drrumlinoid or fluting (direction unknown) Striation (direction known) Striation or groove (direction unknown) 2 1 Striations with age relationship (direction known, 1 is oldest) Interpreted Ice-Flow Direction Early topographically controlled flows towards the southeast Flows due to the development of ice-centre west of study area during glacial maximum Southwest flows due to eastward shift of ice-centre during late glacial maximum Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek BCGS (182) GSC (10) Till Sample Locations 2-3 kg, subglacial till Abstract Regional till geochemical sampling in the Pendelton Bay area (NTS mapsheet 93K/12) has detected dispersal from known porphyry Cu±Mo±Au mineralization at the Fort showing (MINFILE 93K 093) and identified three new areas of geochemical interest. Situated 30 km southwest of the past producing porphyry Cu±Mo±Au Bell and Granisle mines, the Pendleton Bay area has potential to host new porphyry Cu±Mo±Au mineralization. However, access to the area is limited and glacial sediment cover is extensive. To better assess mineral potential here, 182 subglacial till samples were collected by the British Columbia Geological Survey in 1998 for geochemical analysis of the <63 µm size fraction by inductively coupled plasma emission spectroscopy (ICP-ES) and instrumental neutron activation analysis (INAA). Ice-flow features indicate that glacial dispersal was predominantly towards the east and southeast. The maximum Cu value (522 ppm Cu) is 700 m northeast of the main Fort showing, and th anomalous values greater than the 90 percentile (60 ppm Cu) continue for about 2 km down ice (southeast). The Mo footprint in till at the Fort showing is smaller, with the maximum (29 ppm Mo) occurring 300 m to the northeast, and concentrations fall to near detection limit 800 m to the east. Three additional areas have been identified with anomalous values of Cu (up to 167 ppm), Cr (up to 263 ppm), and Ni (up to 101 ppm). These anomalies provide a starting point for future exploration work in the area. Areas of geochemical interest Regional geochemical dispersal Summary Three new areas of geochemical interest have been identified in Pendleton Bay map area that warrant follow up work. Glacial dispersal in the area ranges from northeast to th southeast, and dispersal of >90 percentile Cu is observed to extend at least 2 km from the Fort showing. Geochemical data will be released in an upcoming Open File report. References Arnold, H., Ferbey, T., and Hickin, A., 2016. Ice-flow indicator compilation, British Columbia and Yukon. British Columbia Ministry of Energy and Mines, British Columbia Geological Survey Open File 2016-4, Geological Survey of Canada Open File 8083, 1:1,750,000 scale. Cui, Y., Miller, D., Nixon, G., and Nelson, J., 2015. British Columbia digital geology. British Columbia Ministry of Energy and Mines, British Columbia Geological Survey Open File 2015-2, digital files. Levson, V.M., 2002. Quaternary geology and till geochemistry of the Babine porphyry copper belt, British Columbia (NTS 93L/9, 16, M/1, 2, 7, 8). British Columbia Ministry of Energy and Mines, British Columbia Geological Survey Bulletin 110, 278 p. Levson, V.M., Mate, D., and Stuart, A.J., 1999. Quaternary geology and drift prospecting studies in the north central Nechako Plateau (93F and K). In: Geological Fieldwork 1998, BC Ministry of Energy, Mines, and Petroleum Resources, British Columbia Geological Survey Paper 1999-1, pp. 16-23. Plouffe, A., and Williams, S.P., 2001. Quaternary geology data: Manson River (93N), Fort Fraser (93K) and Nechako River (93F), central British Columbia. Geological Survey of Canada, Open File 2270, CD-ROM. Introduction Till sampling in Pendleton Bay area has identified dispersal from Fort porphyry Cu±Mo±Au showing and three new areas of geochemical interest. Extensive till cover, and lack of historical exploration, makes the area ideal for the application of drift exploration methods to help discover new metallic mineralization. Field work was carried out summer of 1998 (see Levson et al., 1999). The Pendleton Bay area has potential to host porphyry Cu±Mo±Au mineralization similar to that at past-producing Bell (MINFILE 093M001) and Grainisle (MINFILE 093L146) mines, 30 km to the northeast. The area is host to 3 documented MINFILE showings: Ice-flow history Studies northwest of the map area identified that dispersal was predominantly to the southeast (Levson, 2002). Ice-flow indicators in the study area suggest ice-flow was mainly to the east and northeast. Topographically controlled flow towards the southeast is observed in parts of the study area, as are late southerly flows. Till sampling for geochemistry 182 samples of subglacial till (2-3 kg) were collected at average depth of 1 m below surface. The <63 µm fraction was analyzed by - INAA at Actlabs; and - ICP-ES at ACME This data set is supplemented by 10 subglacial till samples collected by the Geological Survey of Canada (Plouffe and Williams, 2001). th th th th Geochemical maps were produced using 50 , 70 , 90 , 95 , th and 98 percentile class breaks. 0 5 10 2.5 Kilometres BL FORT OWL EEva EO lmJHSH EEva PJCS PTrCRgs uTrTv PTrCSvb PTrCTum PnTrCTus uTrTvb EMJSPd DTrT DTrT EEva LTrBgb EEva DPAgs uTrTva uTrJSs lmJHvf PTrCRgs DTrTma EEvl MJSLM MJSPsy EGo LTrJTpT LTrgd LTrgd LTrJTpT EGo uTrTvl DPAls DPAsf uTrTv EEva EMJSPd EEvl EEva Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek 125°30'W 125°30'W 126°0'W 126°0'W 54°45'N 54°45'N 54°30'N 54°30'N 0 5 10 2.5 Kilometres BL FORT OWL EEva EO lmJHSH EEva PJCS PTrCRgs uTrTv PTrCSvb PTrCTum PnTrCTus uTrTvb EMJSPd DTrT EEva LTrBgb EEva DPAgs uTrTva uTrJSs LTrBum lmJHvf PTrCRgs DTrTma EEvl MJSLM MJSPsy EGo LTrJTpT LTrgd LTrgd LTrJTpT EGo uTrTvl DPAls DPAsf EEvf uTrTv EEva EMJSPd EEvl EEva Babine Lake Specularite Lake Butterfield Lake Pendleton Bay Fleming Creek 1 2 3 4 1 Fort Showing: Maximum Cu (522 ppm) and th Mo (29 ppm) for study. >98 percentile Zn, Cr, th th and Ni, and >90 percentile As. >90 percentile Cu continues 2 km southeast and 750 m northeast. 2 South Specularite Lake area: Maximum Cr (452 ppm) and Ni (101 ppm) for study. Also th th contains >95 percentile Cu and >90 percentile Au. 3 South Butterfield Lake area: 3 samples over th 2.5 km with up to >98 percentile Cu and th th Cr, >95 percentile Au, and >90 percentile Ni. 4 th Fleming Creek area: >98 percentile Ni and Au th in one sample, >98 percentile Cu in a second. Showing Deposit Type Commodities BL 093K054 NA Cu Fort 093K093 Cu, Ag, Mo, Pb, Zn, Au OWL 093K103 Cu, Ag, Au, Zn, Pb Porphyry Cu±Mo±Au (L04) Cu±Ag quartz veins (I06) Porphyry Cu±Mo±Au (L04) MINFILE No. New till geochemical targets for potential porphyry Cu±Mo±Au mineralization in the Pendleton Bay area 1 1 2 A.L. Bustard , T. Ferbey , and V.M. Levson 1 British Columbia Geological Survey, Victoria, BC, V8W 9N3 2 Quaternary Geosciences, Victoria, BC, V8P 2Z8 G Y E E O V L R O U G S I C A L C O L H U S M I T B I I R A B British Columbia Geological Survey GeoFile 2017-5 (Arnold et al., 2016) Observations [email protected]
Transcript of New till geochemical targets for potential porphyry Cu±Mo...
BL
FORT
OWL
125°30'W
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126°0'W
126°0'W
54°45'N 54°45'N
54°30'N 54°30'N
0 5 102.5Kilometres
61 - 84 (105)
85 - 92 (32)
93 - 126 (36)
127 - 152 (9)
153 - 170 (6)
171 - 452 (4)
Cr (ppm)<63 µm
INAA
Babine
LakeSpecularite
Lake
ButterfieldLake
PendletonBay
FlemingCreek
BL
FORT
OWL
125°30'W
125°30'W
126°0'W
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10 - 29 (98)
30 - 35 (38)
36 - 43 (38)
44 - 47 (8)
48 - 56 (6)
57 - 101 (4)
Ni (ppm)<63 µm
Aqua Regia, ICP-ES
Babine
Lake
SpeculariteLake
ButterfieldLake
PendletonBay
FlemingCreek
BL
FORT
OWL
125°30'W
125°30'W
126°0'W
126°0'W
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0 5 102.5Kilometres
3.8 - 15.2 (96)
15.3 - 16.9 (41)
17.0 - 18.7 (37)
18.8 - 20.2 (8)
20.3 - 20.9 (6)
21.0 - 32.0 (4)
As (ppm)<63 µm
INAA
Babine
Lake
SpeculariteLake
ButterfieldLake
PendletonBay
FlemingCreek
BL
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OWL
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0 5 102.5Kilometres
-2.0 - 5.0 (143)
5.1 - 9.0 (33)
9.1 - 11.0 (7)
11.1 - 18.2 (5)
18.3 - 31.0 (4)
Au (ppb)<63 µm
INAA
Babine
Lake
SpeculariteLake
ButterfieldLake
PendletonBay
FlemingCreek
BL
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126°0'W
126°0'W
54°45'N 54°45'N
54°30'N 54°30'N
0 5 102.5Kilometres
-1.0 - 1.0 (179)
1.1 - 2.0 (5)
2.1 - 5.9 (4)
6.0 - 29.0 (4)
Mo (ppm)<63 µm
Aqua Regia, ICP-ES
Babine
Lake
SpeculariteLake
ButterfieldLake
PendletonBay
FlemingCreek
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0 5 102.5Kilometres
9.00 - 41.0 (103)
41.1 - 46.0 (36)
46.1 - 59.7 (33)
59.8 - 70.9 (10)
71.0 - 117 (6)
118 - 522 (4)
Cu (ppm)<63 µm
Aqua Regia, ICP-ES
Babine
Lake
SpeculariteLake
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PendletonBay
FlemingCreek
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54°30'N 54°30'N
0 5 102.5Kilometres
BL
FORTOWL
EEva
EO
lmJHSH
EEva
PJCSPTrCRgs
uTrTv
PTrCSvb
PTrCTum
PnTrCTus
uTrTvb
EMJSPd
DTrT
DTrT
EEva
LTrBgb
EEva
DPAgs
uTrTva
uTrJSs
LTrBum
lmJHvf
PTrCRgs
DTrTma
EEvl
MJSLM
MJSPsy
EGo
LTrJTpT
LTrgd
LTrgd
LTrJTpT
EGo
uTrTvlDPAls
DPAsf
EEvf
uTrTv
EEva
EMJSPd
EEvl
EEva
Babine
LakeSpecularite
Lake
ButterfieldLake
PendletonBay
FlemingCreek
Geology (Cui et al., 2015)
Paleogene
EE
Nechako Plateau Group -Endako Formationva: andesitic volcanic rocksvl: coarse volcaniclastic andpyroclastic volcanic rocksvf: rhyolite, felsic volcanic rocks
EO
Nechako Plateau Group - OotsaLake Formationrhyolite, felsic volcanic rocksva: andesitic volcanic rocks
EGo
Goosly plutonic suitegranodioritic intrusive rocks;granite, alkali feldspar graniteintrusive rocks
Jurassic
lmJHvfHazelton Groupcoarse volcaniclastic andpyroclastic volcanic rocks
lmJHSHHazelton Group - Saddle HillFormationundivided volcanic rocks
MJSPsySpike Peak intrusive suitesyenitic to monzonitic intrusiverocks
MJSLMEndako Batholith - Stag Lakeplutonic suite - McKnab phasequartz dioritic intrusive rocks
EMJSPdSpike Peak intrusive suitedioritic intrusive rocks
Triassic to Jurassic
uTrJSsSitlika assemblage - clastic unitundivided sedimentary rocks
LTrJTpTTopley intrusive suite - TochchaLake stockdioritic intrusive rocks
Triassic
uTrT
Takla Groupv: undivided volcanic rocksva: andesitic volcanic rocksvb: basaltic volcanic rocksvl: coarse volcaniclastic andpyroclastic volcanic rocks
LTrgdunnamed granodioritic intrusiverocks
LTrB
Permian to Jurassic
PJCS
Cache Creek complex -Sowchea successionmudstone, siltstone, shale fineclastic sedimentary rocks
Permian to Triassic
PnTrCTusCache Creek complex -Trembleur ultramafite unitserpentinite ultramafic rocks
PTrCTumCache Creek complex -Trembleur ultramafite unitultramafic rocks
PTrCSvbCache Creek complex -Sowchea successionbasaltic volcanic rocks
PTrCRgs
Cache Creek complex -Rubyrock igneous complexgreenstone, greenschistmetamorphic rocks
Carboniferous to Permian
DPA
Asitka Groupgs: greenstone, greenschistmetamorphic rocksls: limestone, marble, calcareousrocks
Devonian to Triassic
DTrT
Taltapin metamorphic complexlower amphibolite/kyanite grademetamorphic rocksma: limestone, marble,calcareous sedimentary rocks
MINFILE Showing
Fault Road
Butterfield Lake intrusivecomplexgb: gabbroic to dioritic intrusive
rocksum: ultramafic rocks
CG
CG
YA
AX
AX
NAc
ST
WR
WR
AX
AX
AX
NAp
QN
QN
QN
NAc
m
NAp
CA
SMSM
SMSM
SMSM
YT
YT
CC
CDCD
BRBR
MTMT
MTMT
PRPR
CRCR
CKCK
BRBR
BRBR
CC
NAb
NAb
CA
OK
YT
Atlin
Nelson
Stewart
Terrace
Quesnel
Kelowna
Smithers
Victoria
Kamloops
Vancouver
PentictonCranbrook
Dease Lake
Revelstoke
Fort Nelson
Port Alberni
Dawson Creek
Williams Lake
Prince Rupert
Prince George
Fort St. John
Atlin
Nelson
Stewart
Terrace
Quesnel
Kelowna
Smithers
Victoria
Kamloops
Vancouver
PentictonCranbrook
Dease Lake
Revelstoke
Fort Nelson
Port Alberni
Dawson Creek
Williams Lake
Prince Rupert
Prince George
Fort St. John
116°W
116°W
124°W
124°W
132°W
132°W
58°N
58°N
54°N
54°N
50°N
50°N
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kmCopyright © 2011
British Columbia Geological Survey
BRIT
ISH COLUM
BIA
GEO
LOGICAL SURV
EY
Coast
plutonic
complex
PacificOcean
Ala
ska
Yukon NWT
BC
Alb
erta
USA
eastern
limit
of
Cordilleran
deformation
Chugach
Cache Creek
Wrangellia
Alexander
Yukon-Tanana
Yakutat
Stikinia
Quesnellia
Coast complex
Pacic Rim
North America - platform
Methow
Kootenay
Cadwallader
Chilliwack
Crescent
Bridge River
Harrison Lake
Slide Mountain
AX
WR
CG
YA
YT
OK Okanagan
ST
QN
HA
CD
CK
MT
PR
CR
BR
SM
CC
m
NAb
NAp
North America - craton & cover
NAc
CassiarCA
Outboard
Insular
Intermontane
Ancestral North America
TERRANES
Location of study area. Geology from Colpron and Nelson (2011)
StudyArea
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1 2
BL
FORTOWL
125°30'W
125°30'W
126°0'W
126°0'W
54°45'N 54°45'N
54°30'N 54°30'N
0 5 102.5Kilometres
Ice-Flow IndicatorsField Observations (Levson et al., 1999)
Striation(direction known)
Remote-sensing
Crag-and-tail(direction known)
Drumlin(direction known)
Drrumlinoid or fluting(direction unknown)
Striation(direction known)
Striation or groove(direction unknown)
2
1Striations with age relationship(direction known, 1 is oldest)
Interpreted Ice-Flow Direction
Early topographically controlled flows towards the southeast
Flows due to the development of ice-centre west of study area during glacial maximum
Southwest flows due to eastward shift of ice-centre during late glacial maximum
Babine
Lake SpeculariteLake
ButterfieldLake
PendletonBay
FlemingCreek
BCGS (182)
GSC (10)
Till Sample Locations2-3 kg, subglacial till
AbstractRegional till geochemical sampling in the Pendelton Bay area (NTS mapsheet 93K/12) has detected dispersal from known porphyry Cu±Mo±Au mineralization at the Fort showing (MINFILE 93K 093) and identified three new areas of geochemical interest. Situated 30 km southwest of the past producing porphyry Cu±Mo±Au Bell and Granisle mines, the Pendleton Bay area has potential to host new porphyry Cu±Mo±Au mineralization. However, access to the area is limited and glacial sediment cover is extensive. To better assess mineral potential here, 182 subglacial till samples were collected by the British Columbia Geological Survey in 1998 for geochemical analysis of the <63 µm size fraction by inductively coupled plasma emission spectroscopy (ICP-ES) and instrumental neutron activation analysis (INAA). Ice-flow features indicate that glacial dispersal was predominantly towards the east and southeast. The maximum Cu value (522 ppm Cu) is 700 m northeast of the main Fort showing, and
thanomalous values greater than the 90 percentile (60 ppm Cu) continue for about 2 km down ice (southeast). The Mo footprint in till at the Fort showing is smaller, with the maximum (29 ppm Mo) occurring 300 m to the northeast, and concentrations fall to near detection limit 800 m to the east. Three additional areas have been identified with anomalous values of Cu (up to 167 ppm), Cr (up to 263 ppm), and Ni (up to 101 ppm). These anomalies provide a starting point for future exploration work in the area.
Areas of geochemicalinterest
Regional geochemical dispersal
Summary Three new areas of geochemical interest have been
identified in Pendleton Bay map area that warrant follow up work.
Glacial dispersal in the area ranges from northeast to thsoutheast, and dispersal of >90 percentile Cu is
observed to extend at least 2 km from the Fort showing.
Geochemical data will be released in an upcoming Open File report.
ReferencesArnold, H., Ferbey, T., and Hickin, A., 2016. Ice-flow indicator compilation, British Columbia and Yukon. British Columbia Ministry of Energy and Mines, British Columbia Geological Survey Open File 2016-4, Geological Survey of Canada Open File 8083, 1:1,750,000 scale.
Cui, Y., Miller, D., Nixon, G., and Nelson, J., 2015. British Columbia digital geology. British Columbia Ministry of Energy and Mines, British Columbia Geological Survey Open File 2015-2, digital files.
Levson, V.M., 2002. Quaternary geology and till geochemistry of the Babine porphyry copper belt, British Columbia (NTS 93L/9, 16, M/1, 2, 7, 8). British Columbia Ministry of Energy and Mines, British Columbia Geological Survey Bulletin 110, 278 p.
Levson, V.M., Mate, D., and Stuart, A.J., 1999. Quaternary geology and drift prospecting studies in the north central Nechako Plateau (93F and K). In: Geological Fieldwork 1998, BC Ministry of Energy, Mines, and Petroleum Resources, British Columbia Geological Survey Paper 1999-1, pp. 16-23.
Plouffe, A., and Williams, S.P., 2001. Quaternary geology data: Manson River (93N), Fort Fraser (93K) and Nechako River (93F), central British Columbia. Geological Survey of Canada, Open File 2270, CD-ROM.
Introduction Till sampling in Pendleton Bay area has identified dispersal
from Fort porphyry Cu±Mo±Au showing and three new areas of geochemical interest.
Extensive till cover, and lack of historical exploration, makes the area ideal for the application of drift exploration methods to help discover new metallic mineralization.
Field work was carried out summer of 1998 (see Levson et al., 1999).
The Pendleton Bay area has potential to host porphyry Cu±Mo±Au mineralization similar to that at past-producing Bell (MINFILE 093M001) and Grainisle (MINFILE 093L146) mines, 30 km to the northeast.
The area is host to 3 documented MINFILE showings:
Ice-flow history Studies northwest of the map area identified that dispersal
was predominantly to the southeast (Levson, 2002).
Ice-flow indicators in the study area suggest ice-flow was mainly to the east and northeast. Topographically controlled flow towards the southeast is observed in parts of the study area, as are late southerly flows.
Till sampling for geochemistry 182 samples of subglacial till (2-3 kg) were collected at
average depth of 1 m below surface.
The <63 µm fraction was analyzed by - INAA at Actlabs; and - ICP-ES at ACME
This data set is supplemented by 10 subglacial till samples collected by the Geological Survey of Canada (Plouffe and Williams, 2001).
th th th th Geochemical maps were produced using 50 , 70 , 90 , 95 ,
thand 98 percentile class breaks.
0 5 102.5Kilometres
BL
FORT OWL
EEva
EO
lmJHSH
EEva
PJCSPTrCRgs
uTrTv
PTrCSvb
PTrCTum
PnTrCTus
uTrTvb
EMJSPd
DTrT
DTrT
EEva
LTrBgb
EEva
DPAgs
uTrTva
uTrJSs
lmJHvf
PTrCRgs
DTrTma
EEvl
MJSLM
MJSPsy
EGo
LTrJTpT
LTrgd
LTrgd
LTrJTpT
EGo
uTrTvlDPAls
DPAsf
EEvf
uTrTv
EEva
EMJSPd
EEvl
EEva
Babine
LakeSpecularite
Lake
ButterfieldLake
PendletonBay
FlemingCreek
125°30'W
125°30'W
126°0'W
126°0'W
54°45'N 54°45'N
54°30'N 54°30'N
0 5 102.5Kilometres
BL
FORT
OWL
EEva
EO
lmJHSH
EEva
PJCSPTrCRgs
uTrTv
PTrCSvb
PTrCTum
PnTrCTus
uTrTvb
EMJSPd
DTrT
DTrT
EEva
LTrBgb
EEva
DPAgs
uTrTva
uTrJSs
LTrBum
lmJHvf
PTrCRgs
DTrTma
EEvl
MJSLM
MJSPsy
EGo
LTrJTpT
LTrgd
LTrgd
LTrJTpT
EGo
uTrTvlDPAls
DPAsf
EEvf
uTrTv
EEva
EMJSPd
EEvl
EEva
Babine
Lake SpeculariteLake
ButterfieldLake
PendletonBay
FlemingCreek
1
2
3
4
1 Fort Showing: Maximum Cu (522 ppm) and thMo (29 ppm) for study. >98 percentile Zn, Cr,
th thand Ni, and >90 percentile As. >90 percentileCu continues 2 km southeast and 750 mnortheast.
2 South Specularite Lake area: Maximum Cr(452 ppm) and Ni (101 ppm) for study. Also
th thcontains >95 percentile Cu and >90 percentile Au.
3 South Butterfield Lake area: 3 samples over th2.5 km with up to >98 percentile Cu and
th thCr, >95 percentile Au, and >90 percentile Ni.
4thFleming Creek area: >98 percentile Ni and Au
thin one sample, >98 percentile Cu in a second.
Showing Deposit Type Commodities
BL 093K054 NA Cu
Fort 093K093 Cu, Ag, Mo, Pb, Zn, Au
OWL 093K103 Cu, Ag, Au, Zn, Pb
Porphyry Cu±Mo±Au (L04)
Cu±Ag quartz veins (I06)Porphyry Cu±Mo±Au (L04)
MINFILE No.
New till geochemical targets for potential porphyry Cu±Mo±Au mineralization in the Pendleton Bay area1 1 2A.L. Bustard , T. Ferbey , and V.M. Levson
1British Columbia Geological Survey, Victoria, BC, V8W 9N3 2Quaternary Geosciences, Victoria, BC, V8P 2Z8
G
YE EO VL RO UG SICAL
COLH US MIT BI IR A
B
British Columbia Geological SurveyGeoFile 2017-5
(Arnold et al., 2016) Observations
