Active Gold Exploration in Minnesota's Greenstone · PDF filea d a M i n n e s o t a,U S A...
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2 3 1 Map A 4 Big Fork West Big Fork East Linden Grove Virginia Horn 31 36 36 31 31 6 1 6 1 6 31 36 31 31 36 See Enlarged Vermilion District Area Below at a 1:100,000 Print Scale. (Township 61-63, Range 13-15) See Enlarged Virgina Horn Area Left at a 1:100,000 Print Scale (Township 58-59, Range 15-17) 0 1 2 3 4 Miles 0 2 4 6 8 10 Miles 0 1 2 3 4 Miles Vermilion District T.145 T.146 T.147 T.148 T.149 T.150 T.151 T.152 T.153 T.154 T.155 T.156 T.157 T.158 T.159 T.160 T.161 T.162 T.163 R.36 R.35 R.34 R.33 R.32 R.31 R.30 R.29 R.28 R.27 R.26 R.25 R.27 R.26 R.25 R.24 R.23 R.22 R.21 R.20 R.19 R.18 R.17 R.16 R.15 R.14 R.13 R.12 R.11 R.10 R.9 R.8 R.7 R.6 R.5 R.4 T.69 T.68 T.67 T.66 T.65 T.64 T.63 T.62 T.61 T.60 T.59 T.58 T.57 R.6 R.5 R.4 Duluth Complex Cu+Ni+PGM+TiO2 Exploration T.62 R.26 R.25 R.24 R.23 R.22 R.21 R.20 R.19 T.63 T.61 T.60 T.59 T.58 T.57 R.18 R.17 R.16 R.15 R.14 R.13 T. 59 R. 15 R. 16 R. 17 5 R. 14 R. 13 R. 15 T. 62 T. 61 Quetico Subprovince Wawa Subprovince Wabigoon Subprovince Rainy River Kenora/Red Lake Mine Centre Hammond Reef Map A Map A Map B Map B 3 2 1 5 4 6 R.25 R.26 R.27 R.28 R.29 R.30 R.31 R.32 R.33 R.34 R.35 R.36 R.27 R.25 R.26 R.24 R.23 R.22 R.21 R.20 R.19 R.18 R.17 R.16 R.15 R.14 R.13 R.12 R.11 R.10 R.9 R.8 R.7 R.37 Upper Red Lake Lake of the Woods Lake Winnibigoshish Cass L. O n t a r i o , Ca n ad a M i n n e s o t a , U SA Minnesota, U.S.A. Ontario, Canada Wawa Wabigoon Winnipeg R. English River Quetico Wawa Abitibi Uchi Berens Sachigo P enok e a n B i wa b ik I r on F o r m ation Penokean Pokegama Quartzite (Yellow) Printed Map Scale: 1:182,500 Base Map: 1:500:000 After Jirsa et al. (2010), OGS (1993, 2010) 0 10 20 30 40 Miles Printed Map Scale: 1:750,000 Printed Map Scale: 1:100,000 Base Map: 1:500:000 After Jirsa et al. (2010), OGS (1993, 2010) Printed Map Scale: 1:100,000 Base Map: 1:500:000 After Jirsa et al. (2010), OGS (1993, 2010) Printed Map Scale: 1:12,000,000 Base Maps: 1:500,000 (MGS)/1:1,000,000 (OGS) After Jirsa and Southwick (2003), OGS (2010) Active Gold Exploration in Minnesota's Greenstone Belts High Gold Potential Land Available Known Gold Mineralization Bounding Features (Map A & B) Exploration areas (1-6) Public land survey sections Public land survey townships Active State metallic mineral lease Area under consideration for 2011 lease sale Areas ever offered as State mineral lease Plutonic Metasedimentary Volcanoplutonic Subprovince Types Producing Mine Past Producer Exploration Area in Minnesota Gold Visible gold grain in drill core from a Virginia Horn quartz- feldspar porphyry that has 77.9 gpt/2.3 feet. (photo courtesy of Vermillion Gold LLC) Drill core from the Bigfork West Exploration Area . Gold-bearing Iron Formation with 5.3gpt/5 ft. (photo courtesy of Vermillion Gold LLC) New semi-quantitative XRF spot gold concentrations (ppm) in drill core from a granite- greenstone terrane near International Falls . The XRF analyses were done in 2010 by MnDNR. This is an example of the drill core accessible to the public as part of the Drill Core Library's more than 3 million feet of archived materials. This specific section of core was submitted more than 20 years ago, unsplit by an exploration company that was focused on a different interval of bedrock. Known Gold Mineralization Granitic intrusion Syenitic, monzodioritic and dioritic plutons Massive granitic paragneiss and migmatite Schist of sedimentary origin Foliated to gneissic tonalite, diorite and granodiorite Amphibolite (Quetico) Granitic to granodioritic orthogneiss Metagraywacke and slate Iron Formation Conglomerate and lithic sandstone Bedrock Geology (Map A & B) Archean Superior Province Exploration borehole Fault Dike Thrust fault Outcrop (extent not to scale) Mafic intrusion Ultramafic to mafic rocks Mafic metavolcanic & metasedimentary Calc-alkalic metavolcanics Metavolcanic and volcaniclastic rocks, calc-alkalic affinity T. 58 T. 63 References: Jirsa M and Southwick D (2003) Mineral Potential and Geology of Minnesota. Minnesota Geological Survey, University of Minnesota. Retrieved 2010- 12-08. Jirsa M, Boerboom T, Chandler V, Mossler J, and Runkel A (2010) Preliminary Bedrock Geologic Map of Minnesota. Minnesota Geological Survey Map Open-File Report OFR10_02. Scale 1:500,000. Ontario Geological Survey (1993) Bedrock geology, seamless coverage of the Province of Ontario; Ontario Geological Survey, Data Set 6. Scale 1:1,000,000. Ontario Geological Survey (2010) Mineral Deposit Inventory—2010. Lake Superior Rainy Lake Massive granodiorite to granite Intermediate to felsic intrusive Mafic intrusive Iron formation Metaconglomerate, sandstone Metasedimentary rocks & derived gneisses Mafic metavolcanic & metasedimentary Generalized Bedrock Geology Bedrock Geology Base Maps: 1:500,000 (MGS)/1:1,000,000 (OGS) After Jirsa et al. (2010), OGS (1993, 2010) 36 1 6 36 31 1 6 31 36 31 6 1 6 36 31 36 31 1 6 1 6 DDH ND-3 See photo below of gold mineralization 2564ppb Au over 10ft in DDH TC35-5 2480ppb Au over 4ft in DDH TC35-3 3560ppb Au over 0.7ft in DDH RR-1 2780ppb Au over 4.5ft in DDH SS-2A 2765ppb Au over 4.5ft in DDH SS-1 4020ppb Au over 4ft in DDH TC35-1 Map B 6 R. 22 R. 23 R. 24 T. 70 T. 71 T.69 Printed Map Scale: 1:100,000 Base Map: 1:500:000 After Jirsa et al. (2010), OGS (1993, 2010) 0 1 2 3 Miles International Falls High Gold Potential 8016ppb Au over 2.5ft in DDH SS-4 Producing or past producing gold mine Advanced exploration stage Rainy River gold project State Land Available for Exploration
Transcript of Active Gold Exploration in Minnesota's Greenstone · PDF filea d a M i n n e s o t a,U S A...
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Map A
44Big Fork West Big Fork East
Linden Grove
Virginia Horn
3136 3631 31
61616
31363131 36
See Enlarged Vermilion District Area Below at a 1:100,000 Print Scale.(Township 61-63, Range 13-15)
See Enlarged Virgina Horn Area Left at a 1:100,000 Print Scale(Township 58-59, Range 15-17)
0 1 2 3 4Miles
0 2 4 6 8 10Miles
0 1 2 3 4Miles
VermilionDistrict
T.145
T.146
T.147
T.148
T.149
T.150
T.151
T.152
T.153
T.154
T.155
T.156
T.157
T.158
T.159
T.160
T.161
T.162
T.163R.36 R.35
R.34 R.33R.32
R.31R.30 R.29
R.28R.27 R.26 R.25
R.27 R.26 R.25R.24
R.23 R.22 R.21 R.20R.19 R.18
R.17
R.16R.15 R.14
R.13
R.12 R.11
R.10R.9 R.8
R.7
R.6R.5 R.4
T.69
T.68
T.67
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T.63
T.62
T.61
T.60
T.59
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T.57 R.6
R.5R.4
D u l u t h C o m p l e x
Cu+Ni+PGM+TiO2Exploration
T.62
R.26R.25 R.24 R.23 R.22 R.21 R.20 R.19T.63
T.61
T.60
T.59
T.58
T.57
R.18 R.17 R.16 R.15 R.14 R.13
T. 59 R. 15 R. 16 R. 17
55R. 14 R. 13R. 15
T. 62
T. 61
Que t i co Subprov in ce
Wawa Subprov in ce
Wab igoon Subp rov ince
Rainy River
Kenora/Red Lake
Mine Centre
Hammond Reef
Map AMap A
Map BMap B
332211
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44
66
R.25R.26R.27R.28R.29R.30R.31R.32R.33R.34R.35R.36 R.27 R.25R.26 R.24 R.23 R.22 R.21 R.20 R.19 R.18 R.17 R.16 R.15 R.14 R.13 R.12 R.11 R.10 R.9 R.8 R.7R.37
Upper Red Lake
Lake of the Woods
LakeWinnibigoshishCassL.
O n t a r i o , C a n a d a
M i n n e s o t a , U S A
Minnesota, U.S.A.
Ontario, Canada
Wawa
WabigoonWinnipeg R.
English RiverQueticoWawa
Abitibi
UchiBerens
Sachigo
Penokean B iwabik Iron Format ion
Penokean Pokegama Quartzite (Yellow)
Printed Map Scale: 1:182,500Base Map: 1:500:000After Jirsa et al. (2010), OGS (1993, 2010)
0 10 20 30 40Miles
Printed Map Scale: 1:750,000
Printed Map Scale: 1:100,000Base Map: 1:500:000After Jirsa et al. (2010), OGS (1993, 2010)
Printed Map Scale: 1:100,000Base Map: 1:500:000After Jirsa et al. (2010), OGS (1993, 2010)
Printed Map Scale: 1:12,000,000Base Maps: 1:500,000 (MGS)/1:1,000,000 (OGS)After Jirsa and Southwick (2003), OGS (2010) Active Gold Exploration in Minnesota's Greenstone BeltsHigh Gold PotentialLand Available Known Gold Mineralization
Bounding Features (Map A & B)Exploration areas (1-6)
Public land survey sectionsPublic land survey townships
Active State metallic mineral leaseArea under consideration for 2011 lease sale
Areas ever offered as State mineral lease
PlutonicMetasedimentaryVolcanoplutonic
Subprovince TypesProducing MinePast ProducerExploration Areain Minnesota
Gold
Visible goldgrain in drillcore from aVirginiaHorn quartz-feldsparporphyry thathas 77.9 gpt/2.3feet.(photo courtesyof VermillionGold LLC)
Drill core from the Bigfork West Exploration Area. Gold-bearing Iron Formation with 5.3gpt/5 ft.(photo courtesy of Vermillion Gold LLC)
New semi-quantitativeXRF spot goldconcentrations (ppm) indrill core from a granite-greenstone terrane nearInternational Falls. TheXRF analyses were donein 2010 by MnDNR.This is an example of thedrill core accessible tothe public as part of theDrill Core Library's morethan 3 million feet ofarchived materials. Thisspecific section of corewas submitted morethan 20 years ago,unsplit by an explorationcompany that wasfocused on a differentinterval of bedrock.
K n o w n G o l d M i n e r a l i z a t i o n
Granitic intrusionSyenitic, monzodioritic and dioritic plutonsMassive granitic paragneiss and migmatite
Schist of sedimentary origin
Foliated to gneissic tonalite, diorite and granodioriteAmphibolite (Quetico)
Granitic to granodioritic orthogneiss
Metagraywacke and slateIron FormationConglomerate and lithic sandstone
Bedrock Geology (Map A & B)Archean Superior Province
Exploration borehole
Fault
DikeThrust fault
Outcrop (extent not to scale)
Mafic intrusionUltramafic to mafic rocksMafic metavolcanic & metasedimentaryCalc-alkalic metavolcanicsMetavolcanic and volcaniclastic rocks, calc-alkalic affinity
T. 58
T. 63
References:Jirsa M and Southwick D (2003) Mineral Potentialand Geology of Minnesota. Minnesota GeologicalSurvey, University of Minnesota. Retrieved 2010-12-08.Jirsa M, Boerboom T, Chandler V, Mossler J, andRunkel A (2010) Preliminary Bedrock GeologicMap of Minnesota. Minnesota Geological SurveyMap Open-File Report OFR10_02. Scale1:500,000.Ontario Geological Survey (1993) Bedrockgeology, seamless coverage of the Province ofOntario; Ontario Geological Survey, Data Set 6.Scale 1:1,000,000.Ontario Geological Survey (2010) Mineral DepositInventory—2010.
LakeSuperior
RainyLake
Massive granodiorite to graniteIntermediate to felsic intrusive
Mafic intrusive
Iron formationMetaconglomerate, sandstone
Metasedimentary rocks& derived gneisses
Mafic metavolcanic & metasedimentary
Generalized Bedrock Geology
Bedrock Geology Base Maps: 1:500,000 (MGS)/1:1,000,000 (OGS)After Jirsa et al. (2010), OGS (1993, 2010)
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36 31
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36 31 36 31
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DD H N D -3S e e p h o to b e l o w o fgo l d m i n e r a li z at i o n
2564ppb Auover 10 f tin DDH TC35-5
2480ppb Auover 4 f tin DDH TC35-33560ppb Au
over 0 .7 f tin DDH RR-1
2780ppb Auover 4 .5 f tin DDH SS -2A
2765ppb Auover 4 .5 f tin DDH SS -1
4020ppb Auover 4 f tin DDH TC35-1
Map B
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R. 22R. 23R. 24
T. 70
T. 71
T.69Printed Map Scale: 1:100,000Base Map: 1:500:000After Jirsa et al. (2010), OGS (1993, 2010)
0 1 2 3MilesInternational Falls
High Gold Potential
8016ppb Au over 2 .5 f tin DDH SS -4
Producing or past producing gold mineAdvanced explorationstage Rainy Rivergold project
State Land Availablefor Exploration
