Geochemistry and economic potential of tectonic terranes ... · Geochemistry and economic potential...

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Geochemistry and economic potential of tectonic terranes at the north flank

of the Flin Flon Belt.

by Paul Gilbert

Kisseynew Lake

KississingLake

Wekusko

La ke

FileLa ke

Wildn estLake

ElbowLake

Reed Reed Lake

T HO

AtlanticOcean

H udsonBay

NA IN

SUPERIOR

RAE

SLAV

E

HE ARNE

WYO

MIN

G

130 W50 N

50 N

60 W

KISSEYNEW DOMAIN'south flank'

F

20 km

PHANEROZOICCOVER

Amisk collage

FLIN FLON BELT

STUDY AREA

Northern FF Belt: Geochemical Assemblages

Simplified tectonic history of the Flin Flon Belt

Pre-accretion period (1.906 – 1.881 Ga) -‘Juvenile arc’1.9 – 1.88 Juvenile arc and BABB volcanism, and turbidite

sedimentation -Flin Flon arc assemblageElbow-Athapapuskow ocean-floor assemblage

Tectonic accretion - 1.88 to 1.87 Amisk collage

Post-accretion period (1.876 – 1.838 Ga) -‘Successor arc’

Juvenile calk-alkaline plutons

1.87 – 1.847 Marine to subaerial sedimentation1.84 – 1.81 Peak orogeny, continental collision

Northern FF Belt: Geochemical Assemblages

Wabishkok Lake

Lac Aimee

Naosap Lake

Alberts Lake

Embury Lake

road

Gabbro (Juvenile Arc)Granitoid rocks Missi Group(Successor Arc)

0 5 10 km

TartanDismalWabishkokAnimusLac Aimee

Sourdough BayMikanagan

Northern FF Belt: Fault Blocks

Wabishkok Lake

Lac Aimee

Naosap Lake

Alberts Lake

Embury Lake

road

Gabbro (Juvenile Arc)Granitoid rocks Missi Group(Successor Arc)

0 5 10 km

TartanDismalWabishkokAnimusLac Aimee

Sourdough BayMikanagan

Northern FF Belt: Geochemical Assemblages

Northern FF Belt: Fault Blocks

Selected Element Averages

2 %Fault Block Tectonic type SiO2 TiO % FeO total

% Th ppm

Wabishkok Lake,Lac Aimée,

Sourdough BayARC 56 0.5 10.6 0.7

Animus Lake E-MORB 50 1.6 12.6 0.5

Mikanagan Lake E-MORB 51 1.9 13.4 0.9

Animus Lake N-MORB 49 0.6 11.4 0.1

Lac Aimée TRANSArc/E-MORB

55 1.1 13.6 0.8

Dismal Lake TRANSN-MORB/Arc

50 0.9 11.2 0.1

ARC Wabishkok Lac Aimee Sourdough Bay

MORB-LIKE Animus Mikanagan

JUVENILE ARC

OCEAN-FLOOR

0 1 2 3 4 5 6 7 8 9 100.0

0.5

1.0

1.5

2.0

2.5

TiO2

MgO

Th NbLa CeNdSm ZrHf Eu Ti Dy Y YbLu .1

1

10

100

Roc

k / N

-MO

RB Flow Gabbro

Th NbLa CeNdSm Zr Hf Eu Ti Dy Y YbLu .1

1

10

100

Rock

/ N

-MO

RB

Animus Lake N-MORB

Th NbLa Ce NdSmZr Hf Eu Ti Dy Y Yb Lu .1

1

10

Roc

k / N

-MO

RB

100

Lac Aimee Transitional (Arc/MORB-like)

.1

1

10

100

ThNbLaCeNdSmZr Hf Eu Ti GdDy Y Er YbLu

Lac Aimee suite

Roc

k / N

-MO

RB

.1

1

10

100

Th NbLaCeNdSmZr HfEu TiGdDyY Er YbLu

Wabishkok Lake Arc

Rock

/ N

-MO

RB

.1

1

10

100

ThNbLaCeNdSmZrHfEu TiGdDy Y ErYbLu

Dismal Lake Transitional (MORB/arc- like)

Roc

k / N

-MO

RB

Lac Aimee Animus Lake

Wabishkok Lake Dismal Lake

Ani mus Lake E-type MORB

1 ARC BASALTS

·

·

·

enrichment of LREE + Th

Nb negative anomaly

negative profile due to HFSE (Ti, Zr and Hf)

2 E-MORB BASALTS - e.g. ANIMUS LAKE BASALT

·

·

·

REE contents similar to MORB, but moderately higher LREE

No REE depletion

No Nb spike

ZONE

LAKE

FAU

LTA

NIM

USAN

IMU

S

Mil ls Is.

NORTH AIMEE GABBRO

LAC AIMEE BLOCK

WABISHKOK LAKE BLOCK

54°48'40"101°25'00"

0

kil ometres

2

Naosap Lake

FAULT

101°25'00"54°53'00"54°53'00"

101°37'30"

101°37'30"54°48'40"

Lac Aimee

LAC

AIMEE

Lake

LAK

E

Animus

Alberts

Lake

SOURDOUGH BAY BLOCK

FaultAnticline(F ,F )1 2

Syncline(F ,F )1 2

N-type MORB

Mineralization (b ase metal)

Volcanic Rocks

E-type MORB (flow/intrusive)Arc

Transitional (Arc/MORB-like basalt)

Turbidite Sediment

Gabbroic

Granitoid

Intrusive Rocks

ANIMUS LAKE BLOCK

Wabishkok Lake

Th NbLa CeNdSm ZrHf Eu Ti Dy Y YbLu .1

1

10

100

Roc

k / N

-MO

RB Flow Gabbro

Th NbLa CeNdSm Zr Hf Eu Ti Dy Y YbLu .1

1

10

100

Rock

/ N

-MO

RB

Animus Lake N-MORB

Th NbLa Ce NdSmZr Hf Eu Ti Dy Y Yb Lu .1

1

10

Roc

k / N

-MO

RB

100

Lac Aimee Transitional (Arc/MORB-like)

.1

1

10

100

ThNbLaCeNdSmZr Hf Eu Ti GdDy Y Er YbLu

Lac Aimee suite

Roc

k / N

-MO

RB

.1

1

10

100

Th NbLaCeNdSmZr HfEu TiGdDyY Er YbLu

Wabishkok Lake Arc

Rock

/ N

-MO

RB

.1

1

10

100

ThNbLaCeNdSmZrHfEu TiGdDy Y ErYbLu

Dismal Lake Transitional (MORB/arc- like)

Roc

k / N

-MO

RB

Lac Aimee Animus Lake

Wabishkok Lake Dismal Lake

Ani mus Lake E-type MORB

Selected Element Averages

2 %Fault Block Tectonic type SiO2 TiO % FeO total

% Th ppm

Wabishkok Lake,Lac Aimée,

Sourdough BayARC 56 0.5 10.6 0.7

Animus Lake E-MORB 50 1.6 12.6 0.5

Mikanagan Lake E-MORB 51 1.9 13.4 0.9

Animus Lake N-MORB 49 0.6 11.4 0.1

Lac Aimée TRANSArc/E-MORB

55 1.1 13.6 0.8

Dismal Lake TRANSN-MORB/Arc

50 0.9 11.2 0.1

0 1 2 3 4 5 6 7 8 9 100.0

0.5

1.0

1.5

2.0

2.5

TiO2

MgO

Lac Aimee Transitional(arc / MORB-like)

Animus Lake N-MORB

JUVENILE ARC

OCEAN-FLOOR

N-MORB

E-MORB

Thol

CA

Arc

TRANSITIONALMORB/ARC-like

Th Nb/ 16

Hf/ 3

WabishkokLac AimeeSourdough Bay

Lac Aimee TRANSITIONALARC/MORB-like

E-MORB

N-MORB

Animus

Animus

Dismal

ARC

Arc-rift terranes

·

·

MORB-like basalts + ferrobasalts

Intra-arc extension-related turbidite basins

ZONE

LAKE

FAU

LTA

NIM

USAN

IMU

S

Mil ls Is.

NORTH AIMEE GABBRO

LAC AIMEE BLOCK

WABISHKOK LAKE BLOCK

54°48'40"101°25'00"

0

kil ometres

2

Naosap Lake

FAULT

101°25'00"54°53'00"54°53'00"

101°37'30"

101°37'30"54°48'40"

Lac Aimee

LAC

AIMEE

Lake

LAK

E

Animus

Alberts

Lake

SOURDOUGH BAY BLOCK

FaultAnticline(F ,F )1 2

Syncline(F ,F )1 2

N-type MORB

Mineralization (b ase metal)

Volcanic Rocks

E-type MORB (flow/intrusive)Arc

Transitional (Arc/MORB-like basalt)

Turbidite Sediment

Gabbroic

Granitoid

Intrusive Rocks

ANIMUS LAKE BLOCK

Wabishkok Lake

• Turbidite in Lac Aimée Block with scour structure and graded bedding

• Rhyolite flow in Lac Aimée Blockwith flow banding

• Fragmental rhyolite flow east of Wabishkok Lake

Pistol

Dismal

Lake

La ke

KotykLa ke

Wab ishkok LakeBlueberry

Lake

KOTYK LAKEINTRUSIONPISTOL

LAKEGRANODIO RITE

0 1 2 3kilometres

Geological contact (approxima te)

Wabishk ok Lake antiform Minerali zation (pyrite+pyrrhotite) Diamond-dri ll hole Electromagnetic conducto r Gravel road, track Not e: Unit numbers correspond to those on Preliminary Map 2001F-3

SYMBOLS

(4a) Granodiorite, granite (4b) Quartz diorite, tonalite, diorite, granodiorite ( / / / with enclaves of unit 1) (3a) Gabbro, hornblendite (3b) Pyroxenite (2a) Rhyolite, massive to fragmental (2b) Feldspar-quartz porphyry (1a-h) Basalt, gabbro, amphibolite, mafic gneiss; minor volcanic breccia

LEGEND

101 40’00”0

101 40’00”0

101 25’ 00”0

101 25’00”0

54 53’00”0 54 53’00”0

54 56’00”054 56’00”0

10

100

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Roc

k/Ch

ondr

ite

Rhyolite enclave within Kotyk gabbroRhyolite unit in southwest part ofWabishkok Lake

10

100

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Roc

k/Ch

ondr

ite

Wabishkok rhyolite

Flin Flon Mine rhyolite

0 10 20 30 40 50.1

1

Th/N

b

Yb/ .22

Flin Flon extension-related rhyolites

Flin Flon Mine rhyolite

Flin Flon arc assemblage

rhyolites

Wabishkok rhyolite

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.70

100

200

300

400

Zr

TiO2

Flin Flon arc assemblage

rhyolites

Flin Flon Mine rhyolite(main phase)

Zr/T

iO =

0.2

82

Zr/T

iO =

0.13

2

Zr/TiO

= 0.065

2

Zr/TiO = 0.04

2

Zr/TiO = 0.0162

Flin Flon extension-related rhyolites

Wabishkok rhyolite

10

Type F111a Archeanrhyolite (Lesher et al.,1986)

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Roc

k/Ch

ondr

ite

Wabishkok rhyolite

100

Zr/ 10 Y

Ti/ 100

F1

F11

F111b

Wabishkok rhyolite

F111a

Fault Blocks Tectonic AffinityBlock Arc E-MORB N-MORB Transitional Felsic volc Turbidites Rifting

Wabishkok + +

Lac A imée + + + + +

Sourdough + +

Animus + +

Mikanagan + + +

Dismal + ? ?

+

+

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