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2006 Field Report:Aputitooq Mountain, Northwest Kapisillit

Map Sheet (64V2 Syd) andItilleq Fjord, Itsaq Gneiss Complex Sampling

(Parts of UTM Zone 22NW)

Venessa Bennett and Joe Hiess1. 2.

1

2

. Department of Earth Sciences, MUN, St Johns, Newfoundland, Canada, A1B 3X5

. Research School of Earth Sciences, Australian National University

Canberra ACT 0200, Australia




Venessa Bennett and Joe Hiess1. 2.

1

2

. Department of Earth Sciences, MUN, St Johns, Newfoundland, Canada, A1B 3X5

. Research School of Earth Sciences, Australian National University





V and Joe Hiess1. 2.

enessa Bennett

1. Department of Earth Sciences, MUN, St Johns, Newfoundland, Canada, A1B 3X5

2. Research School of Earth Sciences, Australian National University


September 2006 - Kapisillit Field Report Bennett and Hiess

INTRODUCTION and OBJECTIVES

The following descriptive notes accompany 1:50 000 scale hard copy geologic maps

completed by the authors and given to GEUS following completion of the 2006 field season.

The report outlines the results of bedrock mapping completed in the northwestern region of

the Kapisillit Map sheet in the vicinity of Aputitooq mountain and Itilleq Fjord, representing

parts of UTM zone 22NW (Figs. 1 & 2). Individual traverse spacing was at a density of 1 to

3 km, appropriate for final map compilation at between 1: 50 000 and 1: 100 000 scale. 1: 40

000 scale black and white photographs were used to construct a working geologic map for

each respective area. Geologic datasets were then transferred onto 1:50 000 scale topographic

basemaps, which will ultimately be used for final 1: 100 000 scale compilation.

The two areas described in this report were mapped by Joe Hiess (Australian National

University; Ph. D candidate) and Venessa Bennett (Memorial University of Newfoundland;

Post doctoral fellow) during the interval from July 9 - 27th. Work was completed out of four

helicopter camps, three in map area 1, Aputitooq mountain and one in map area 2, Itilleq

Fjord (Fig. 2). The report is divided into two parts, the first describing the geology of map

area 1, Aputitooq mountain and the second, outlining the geology of map area 2, Itilleq

Fjord. Two appendices are also provided. Appendix 1 provides a photographic database

consisting of representative images of each major mappable unit. Appendix 2 provides

details on the application of digital mapping techniques during 2006 mapping season.

2

Kapisillit Map SheetKapisillit Map SheetKapisillit Map SheetKapisillit Map Sheet

22SW

22NW

22NE

22SE

A

Kapisillit Map SheetKapisillit Map SheetKapisillit Map Sheet

22SW

22NW 22NE

22SE

B

64 No

64 No

64 No

64.5 No

64.5 No

64.5 No

65 No

65 No

65 No

52 Wo

52 Wo

52 Wo

51 Wo

51 Wo

51 Wo 50 W

o50 W

o50 W

o

Figure 1: (A)(B)

Regional satellite image of southwest Greenland with Kapisillit map sheet location marked. Image extracted fromGoogle Earth. Part of geological map of southwest Greenland, Sheet 2, Frederikshab Isblank - S ndre Str mfjord. Inset

map shows location within Greenland. Location of the Kapisillit map sheet marked.ø øC


3

Map Area 1

Map Area 2

Allukersuaq

Camp 1Camp 1Camp 1

Camp 2Camp 2Camp 2

Camp 3Camp 3Camp 3

Camp 4Camp 4Camp 4

Figure 2: 1: 100 000 scalecompilation map of Kapisillitarea (modified after Friend 2005).Location of two designated mapareas and camp sites described inreport are marked.


4

PART IAputitooq Mountain

Northwest Kapisillit Map Sheet(Part of UTM Zone 22NW)

Venessa Bennett and Joe Hiess








1.0 OVERVIEW – Aputitooq mountain map area, northwest Kapisillit Map

Sheet

Bedrock mapping of the northwest Kapisillit map sheet between the latitude of -50o 21’W

and -50o 10’W and longitude of 64o 17’N and 64o 25’N took place out of three helicopter

camps from July 9 - 14th (1 - UTM 22NW 534511 7136266), 15-20th (2 - UTM 22NW

534275 7133108) and 24- 28th (3 - UTM 22NW 533123 7137809), respectively. Results of

previous mapping in the area are shown in Fig. 3A. Five main lithological units were

recognized, including the Nuuk and Amitsoq gneisses, amphibolite, metasediment and an

anorthosite package. Additionally, a regional synform-antiform pair are shown to deform

these lithologies. The synformal structure is centred on Aputitooq mountain, which reaches

an elevation of 1126 meters above sea level. The primary objectives for 2006 fieldwork were

to:

(1) Map the region in sufficient detail to generate a 1: 50 000 scale geologic map.

(2) To better understand the complexity of the regional fold structures as mapped on the

existing compilation (Fig. 3A)

(3) Attempt to understand the tectonostratigraphy of the Aputitooq Mountain synform

with particular focus on its’ relationship to known occurrences of the Itsaq Gneiss

Complex.

6


(An): Anorthosite -Leucogabbro

(Agn): Amitsoq Gneisses,tonalitic - granodioritic(~ 3700 Ma)

(A): Amphibolite;Undifferentiated

(Ngn): Nuuk Gneisses, Bt-Hbl bearing tonaliticto granodioritic orthogneisses (~ 2800 - 3050 Ma).

(Ms): Metasediments

NgnNgn

AA

AnAn

AgnAgn

NgnNgnAgnAgn

MsMs

AnAn

A Map Area 1

U-Pb Geochronology Sample Sites

492206

492234

492218,492219,492220

492202

492209

Camp Sites1 km1 km1 km

B

1 km1 km1 km

50 20’Wo

64 20’No

50 10’Wo

64 25’No

Map Area 1

C

C

Figure 3:(A)

(D)

Map area 1 location map with camp site and U-Pb geochronology localities marked (modified after FriendKapisillit compiliation map 2005); Existing geologicalcompilation for map area 1. Extracted from Sheet 2,geological map of SW Greenland, Frederikshab Isblank -S ndre Str mfjord. atellite image of Map area 1. Imageextracted from Google Earth.

(B)

(C) S2

N.b. JMH U-Pbgeochronology localities not marked

ø ø006 geological map of

Aputitooq Mtn synform (Heiss and Bennett).

1 km1 km1 km

D

Bt-Hbl TTG GneissBt-Hbl TTG GneissBt-Hbl TTG GneissAmphibolite-

Pegmatiteunit

Amphibolite-Pegmatite

unit

Amphibolite-Pegmatite

unit

Bt-granodioriticorthogneiss



PolyphaseTTG

orthogneisscomplex

PolyphaseTTG

orthogneisscomplex

PolyphaseTTG

orthogneisscomplex

PinkGranitePink

GranitePink

Granite

Anorthosite-mafic

complex

Anorthosite-mafic

complex

Anorthosite-mafic

complex

Mafic-intermediate

gneiss

Mafic-intermediate

gneiss

Mafic-intermediate

gneiss

Heterogeneoussupracrustal

package


package


package

7


2.0 REGIONAL GEOLOGY

2.1 Synopsis

The Aputitooq mountain map area is consists of 8 map units that have been

intercalated and deformed into a first-order synform-antiform structure. The map units

include, biotite – hornblende TTG gneiss, a heterogeneous amphibolite – pegmatite unit,

biotite-bearing orthogneiss, a heterogeneous compositional zoned supracrustal package, a

polyphase heterogeneous TTG gneiss complex, weakly deformed granite, anorthosite

complex and an intermediate heterogeneous gneiss-amphibolite unit. Interplay between

elevation and structural topology of the tectonostratigraphic package controls the outcrop

pattern illustrated in Fig 3D. Four deformation events are interpreted for the area (Dn to

Dn+4) and are divided into to pre- and post-assembly phases based on continuity of specific

structural attributes between map units. The area has a complex polymetamorphic history and

all map units have experienced at least one episode of amphibolite facies metamorphism. The

synchoneity of this event is unconstrained. Additionally, several packages are characterized

by mineral assemblages indicative of upper-amphibolite to granulite facies conditions and

textures supporting a polymetamorphic history (e.g. the heterogeneous, compositionally

zoned supracrustal package), which contrast to other map units (e.g. Bt-Hbl banded TTG

orthogneiss, polyphase heterogeneous TTG orthogneiss, weakly deformed granite) that have

not attained these metamorphic grades. The heterogeneous supracrustal package contains

numerous gossans along its strike length, which are locally mineralized (Cp+Py?). Where

observed, mineralization is accompanied by low-grade Ep+Qtz+Chl alteration and a late, SW

trending shear zone. Lithological, structural and metamorphic differences that characterize

8


the tectonostratigraphic package suggest vertical stacking of different tectonic terranes was

an important accretion mechanism that controlled the formation of Aputitooq mountain map

area.

2.2 Lithologies

The reader is referred to Appendix 1, which provides a detailed photographic

database to accompany each of the following descriptions of representative map units

identified in the map area. Plutonic compositional names were determined using QAPF

classification scheme of Streckeisen (1978) and mineral abbreviations are after Kretz (1983).

Eight main lithological units were identified, including;

a) Biotite – Hornblende TTG gneiss.

b) Heterogeneous Amphibolite – Pegmatite unit

c) Biotite-Bearing Orthogneiss

d) Heterogeneous Supracrustal Package

e) Polyphase Heterogeneous TTG Gneiss Complex

f) Weakly Deformed Granite

g) Anorthosite - leucogabbro complex

h) Intermediate Composition Heterogeneous Gneiss-Amphibolite

With the exception of the anorthosite - leucogabbro complex and intermediate gneiss

– amphibolite units (g and h, respectively), the following lithological descriptions

proceed from structurally lowest to highest, as they occur in the Aputitooq mountain

synform (refer to Fig. 4 for tectonostratigraphy).

9

55 66

HomogeneousBanded OrthogneissHomogeneousBanded OrthogneissHomogeneousBanded Orthogneiss

Mafic Amphibolite -Pegmatite UnitMafic Amphibolite -Pegmatite UnitMafic Amphibolite -Pegmatite Unit

Bt GranodioriticOrthogneissBt GranodioriticOrthogneissBt GranodioriticOrthogneiss

Gossanous Supracrustal PackageGossanous Supracrustal PackageGossanous Supracrustal Package

Pink GranitePink GranitePink Granite

Leucogabbro-Tonalite-Anorthosite ComplexLeucogabbro-Tonalite-Anorthosite ComplexLeucogabbro-Tonalite-Anorthosite Complex

Polyphase Orthogneiss ComplexPolyphase Orthogneiss ComplexPolyphase Orthogneiss Complex

Synform HingeSynform HingeSynform Hinge

Antiform HingeAntiform HingeAntiform Hinge

E

1 km1 km1 km

50 20’Wo

64 20’No

50 10’Wo

64 25’No

Map Area 1

11

22

33

44

55

66

A

NgnNgn

AA

AnAn

AgnAgn

NgnNgnAgnAgn

MsMs

AnAn

B

33 44

Gossanous SupracrustalPackageGossanous SupracrustalPackageGossanous SupracrustalPackage



FOLD PLUNGEFOLD PLUNGEFOLD PLUNGE

D

11 22

HomogeneousBanded OrthogneissHomogeneousBanded OrthogneissHomogeneousBanded Orthogneiss




Polyphase Orthogneiss ComplexPolyphase Orthogneiss ComplexPolyphase Orthogneiss Complex

Pink GranitePink GranitePink Granite

C

Figure 4: (A) (B) (C)(D) (E)

Photo profiles across Aputitooq mountain illustrating tectonostratigraphy defining regional synformal structure. Satellite image with location of profiles marked. Existing geological compilation map. NW-SEprofile 1. NW-SE profile 2. NE-SW profile.


10


2.2a Biotite – Hornblende TTG gneiss.

A medium grained tonalitic to granodioritic banded orthogneiss, with subordinate, but

variable dioritic to gabbroic compositional banding comprises the lowermost structural levels

of the Aputitooq mountain synform and represents the most abundant unit in the map area

(Figs. 3, 4; Appendix 1A). Banding ranges from ca. 1 to 40 cm in thickness and consists of;

(a) leucosomal layering (Qtz-Pl-Kfs-Hbl; granodioritic composition) parallel to sub

parallel to pre-existing gneissosity, (Appendix 1A - A, D, E),

(b) medium-grained granitic injection banding (Appendix 1A – B, C) and

(c) compositional banding (Appendix 1A).

Locally, the orthogneiss contains decimeter-scale lenses of coarse-grained amphibolite (Hbl-

Bt-Plag +/- Grt) and paragneiss ranging from semi-pelitic to intermediate (psammitic?) in

composition (Grt-Bt-Plag-Qtz +/-Sil; Appendix 1A- H-K). The consistency of the banding of

this orthogneiss makes in distinct from a overlying orthogneiss bodies occurring at

structurally higher levels. Inferred metasedimentary units within the orthogneiss are fine- to

medium-grained migmatites and have undergone at least one phase of leucosome

development during metamorphism. Leucosomes are parallel – subparallel to a pre-exisiting

Bt schistosity and consist of the assemblage Grt+Qtz+Pl+Kfs (Grt


which constrains the unit to ca. 2925 Ma and thus suggests the unit forms part of the

Kapisillik terrane. An earlier compilation map of the area correlates the orthogneiss unit to

the Nuuk gneiss (Fig. 3A). Further U-Pb geochronology in the Aputitooq mountain synform

area will be undertaken to test these correlations.

2.2b Heterogeneous Amphibolite

A heterogeneous package of amphibolite, pegmatitic granite and locally, metapelite

structurally overlies the Bt-Hbl orthogneiss in the map area (Fig. 4; Appendix 1B – H, K).

The amphibolite phase is fine- to medium-grained varying in composition from basaltic to

dioritic. Compositional banding within the amphibolite component of the map unit varies

from 10 – 40cm in thickness (Appendix 1B - C, F, G, J). Locally garnet-bearing and variably

deformed leucosome (tonalitic – granodioritic in composition) stringers are also

characteristic of the amphibolite phase, consisting of Qtz -Pl +/- Kfs +/- Grt (Appendix 1A –

A, F, J). Amphibolite mineralogy ranges from Hbl-Bt-Pl+/-Qtz to Grt - Bt - Hbl - Plag. The

latter assemblage is typically restricted to distinct compositional layers and are associated

with Grt-bearing leucosome phases (Appendix 1B – F, J).

A light pink, coarse-grained and syn-tectonic granitic phase is spatially associated

with the amphibolite. The granite ranges from equigranular to megacrystic and in low strain

domains is recumbently folded but retains discordant fabric relationships with the

amphibolite host (Kfs-Qtz-Plag-Bt +/- Apatite; Appendix 1B – A-E; Fig. 6A-C).

Discontinuous lenses of medium-grained paragneiss varying from pelitic to semi-

pelitic in composition are also interleaved with the amphibolite and pegmatite units

(Appendix 1B – L-N). Lenses vary in apparent thickness from 1 to 15 m and predominant

mineral assemblages consist of Grt – Bt – Plag – Qtz and Grt – Bt – Plag – Qtz - Sil.

12


2.2c Biotite Granodioritic Orthogneiss

Structurally and topographically above the amphibolite map unit is a medium-

grained, equigranular Bt-orthogneiss that is granodioritic in composition, consists of the

assemblage of Bt-Qtz-Plag-Kfs (Fig. 4; Appendix 1B – H and Appendix 1C). No Hbl was

observed. The orthogneiss is variably migmatitic, which is most prevalent at higher levels of

the unit (i.e. topographic up through unit). Leucosome development is subparallel to the

dominant biotite segregation fabric (Appendix 1C – D-F). Locally, the unit preserves

evidence of polyphase deformation, including recumbent folding of migmatite layering and

mesoscopic intrafolia rootless folds. The orthogneiss unit noticeably lacks metasedimentary

enclaves, but rarely contains rounded amphibolite xenoliths (Appendix 1C – G). Syn-late and

post-tectonic pegmatitic granite suites intrude the Bt-bearing orthogneiss, similar to

underlying amphibolite package. Mesoscopic, sinistral dilatational shear zones are ubiquitous

throughout the Bt- granodioritic orthogneiss and are locally associated with syn-shear

granitic intrusions, suggesting at least one phase of magmatism accompanied shearing in the

unit (Appendix 1C – F).

2.2d Heterogeneous Pelitic Gneiss

A compositionally heterogeneous supracrustal package structurally overlies the

biotite granodioritic orthogneiss (Fig. 4; Appendix 1Di – iv). It varies in apparent thickness

from ca. 5 to 50m and is distinctive in the abundance of gossanous horizons, locally

mineralized, that are contained in the unit (discussed below; Fig. 9). At locality 2006vbe040,

the supracrustal package exhibits a gross compositional zonation from felsic-intermediate

compositions at the base, through to predominantly pelitic compositions in the core which

13


have a transitional boundary with mafic compositions at the highest levels (topographic up;

Fig. 5; Appendix 1Di-iv). Compositional banding varies from 0.5 to 2 m in thickness.

Principal mineralogy for each component includes:

a. Felsic: Qtz-Kfs-Pl-Bt+/- Hbl (fine-grained, equigranular; Appendix 1Di)

b. Intermediate: Grt-Hbl-Bt-Qtz-Kfs-Pl (medium- to coarse-grained,

porphyroblastic; Appendix 1Dii)

c. Pelitic: Grt-Bt-Qtz (Garnetite) through to Grt-Bt-Pl-Qtz; Grt-Bt-Pl-Qtz+/-Sil and

rarely, Grt-Crd-Bt-Pl-Qtz+/Kfs (fine- to locally coarse-grained, equigranular to

porphyroblastic; Appendix 1Diii)

d. Mafic: Bt-Hbl-Pl-Qtz+/- leucosome (Qtz-Pl-Kfs; 15%); Grt-Hbl-Bt-Pl+/-

leucosome (Grt- Qtz-Pl-Kfs; 15%). (fine- to medium-grained, migmatitic to

porphyroblastic; Appendix 1Div).

Adjacent to contacts with the overlying orthogneiss, the mafic phase of the supracrustal

package is characterized by a higher strain gradient (over ca. 2-5 m) compared to the

remainder of the package (Appendix 1Div – D) suggestive of a tectonized contact.

2.2e Polyphase Heterogeneous TTG gneiss complex

A multi-phase, polydeformed orthogneiss complex overlies the heterogeneous

supracrustal package (Fig. 4; Appendix 1E). Contacts are sharp and no obvious timing

relationships between the two units are observed (Appendix 1E – 1B; Note J. Hiess on

underlying supracrustal package). The complex consists of a diverse suite of components

ranging from ultramafic to granitic in composition. The orthogneiss component of the

complex ranges from Hbl-Bt bearing leucocratic tonalite to granodiorite. It is migmatized

14


and has undergone a complex polyphase deformation history indicated by abundant refolded

and sheath-type folds (Appendix 1E – C, D and I). Centimeter to meter scale lenses, rafts,

enclaves and pods of medium- to coarse- grained hornblendite – clinopyroxenite occur within

the orthogneiss. Locally, these phases are discordant to orthogneiss foliations, but are also

overprinted by younger deformation events (Appendix 1E – C, D, F). Mafic intrusions

represent a subordinate component of the complex and range from dioritic to gabbroic in

composition and locally preserve discordant relationships to the surrounding orthogneiss

host. Mafic intrusions are typically elongate, and/or lensoid in geometry and range in

thickness from centimeter to meter scale (Appendix 1E – G, E). A tentative correlation is

made to the Itsaq Gneiss complex based on compositional diversity, polyphase magmatism

and deformation that occurs in this unit, which is not readily correlated to the other map units

in the Aputitooq mountain map area.

2.2f Weakly Deformed Granite

A fine to medium grained, equigranular to phenocrystic granite occurs at the highest

structural and topographic levels in the core of the Aputitooq Mtn synform (Fig. 4; Appendix

1F). It varies from granite to granodiorite in composition, consists of the mineral assemblage

Qtz-Kfs-Plag-Bt +/- Apatite and contains a weak biotite deformational fabric. Abundant

centimeter- to meter-scale enclaves of the underlying polyphase heterogeneous orthogneiss

complex are incorporated in the weakly deformed granite and are concentrated at of the

intrusion margins (Appendix 1F – C, D). The orthogneiss enclaves are aligned parallel to

subparallel to internal biotite deformational fabric.

15


2.2g Anorthosite - leucogabbro complex

A small WNW – ESE trending lens of medium- to coarse-grained heterogeneous

‘anorthosite’ approximately 30m wide (apparent width) that varies in composition from

‘true’ anorthosite (Grt-bearing), leucogabbro (Hbl - Bt - Pl) to Grt - Bt tonalite occurs in the

southeastern corner of the map area (Figs. 3D, 4; Appendix 1G). The lens appears continuous

across the large N-S trending valley delimiting the eastern boundary of the Aputitooq

mountain map area (Fig. 3; Appendix 1G – E, strike ridge of anorthosite complex, viewed

looking east). Banding in the unit is defined by both compositional variations (i.e. mafic to

felsic) and biotite segregations. At least one phase of post-tectonic pegmatite cross cuts the

anorthosite – leucogabbro complex.

2.2h Intermediate Composition Heterogeneous Amphibolite

Medium- to coarse-grained, mafic to intermediate Grt-Hbl gneiss (rare pelitic

horizons) occurs at the east-central margin of the Aputitooq mountain map area (Fig. 3D;

Appendix 1H). The unit is distinctive in the abundance of large garnet porphyroblasts

(estimated 30 – 40% modal abundance). A leucosome phase comprises approximately 10 –

20% of unit. Compositional banding ranges from centimeter- to meter-scale. Mineralogy of

the three main components of the unit consists of:

(a) Mafic: Grt - Hbl - Bt - Pl +/- leucosome (Grt-bearing).

(b) intermediate: Grt-Hbl-Bt-Plag-Qtz+/- leucosome (Grt-bearing).

(c) Strongly weathered, locally gossanous pelitic horizons (Grt - Bt- Qtz - Plag-Kfs

+/ Sil?).

16


2.2 STRUCTURAL GEOLOGY

The regional outcrop pattern that characterizes the Aputitooq mountain map area is

controlled by the first-order interplay between elevation and macroscopic SE plunging, open

folds (antiform-synform pair; Fig. 3A, D and 4E). The south-plunging structures overprint at

least three phases of earlier deformation. Polyphase heterogeneous orthogneiss and weakly

deformed granite outcrop in the Aputitooq mountain synform core and are not observed

elsewhere in the map area. For this preliminary interpretation, the deformation history of the

Aputitooq mountain map area is divided into two main phases, including;

(a) An unconstrained, early interval of protracted deformation (Dn), speculated to be

associated with the pre-assembly history of individual tectonostratigraphic units.

Specific structural attributes of several map units cannot be correlated across all

the map area and are thus, inferred to have formed during this early phase of

deformation.

(b) A younger polyphase deformation history (Dn+1 to Dn+4, respectively),

characterized by structural elements that are common to most of the identified

map units (i.e. post assembly of the tectonostratigraphic pile comprising Aputitooq

mountain map area).

Table 1 summarizes these preliminary structural observations. The following discussion

outlines sequentially, from oldest to youngest, the structures that are diagnostic of each

deformation phase.

17


DeformationEvent

DeformationEvent

DeformationEvent

Structural AttributeStructural AttributeMetamorphic

GradeMetamorphic

GradeMetamorphic

Grade

Dn

Dn+1

Dn+2(Regional)

Dn+3

?

Amphibolite facies

(locally granulite

facies)

Amphibolite

facies

Dilatational shear zones, syn-shear melt intrusion

(sinisitral shear sense; Fig. 6J-M)

Moderate SE plunging, regional open folding

(Aputitooq mountain synform-antiform pair; Figs. 4, 7)

Mesosopic, overturned to recumbent isoclinal folding;

Polyphase compositional banding and

gneissosity; Hornblendite enclave fabric-formation;

Early generation migmatite; mafic intrusions and

subsequent fabric-formation.

Table 1: Summary of deformation history for Aputitooq mountain map area.

Pre

-Assem

bly

Po

s-A

ssem

bly

Dn+4

PolyphaseOrthogneiss

Bt-Hbl BandedOrthogneiss

(Kapisillik affinity?)

Amphibolite -Pegmatite

Unit

Polyphase compositional banding and

gneissosity.

Pre-crenulation leucosome fabric

(Fig. 6A-C).

Breakthrust development (Fig. 6A-D)

Brittle-Ductile

Brittle-Ductile

Brittle-Ductile

Ductile

Brittle

Late NW trending, SE dipping fractures

(Amph+Chl+Qtz filled; Fig. 6N-P)

Lower Amphibolite

- Greenschist Facies

?

18


Dn – Polyphase Early Deformation – (pre-assembly?)

The earliest recognized phase of deformation (Dn) likely represents an extended

interval involving multiple events. Deformational features specific to this time are not readily

correlated across the tectonostratigraphy in the Aputitooq mountain area. Due to their

isolation within a single lithological unit and coupled with the absence of absolute age

constraints, we have broadly grouped these structural elements into Dn until further work

revises timing relationships. In order to build on this preliminary interpretation, a detailed

and integrated structural - geochronological study of each tectonostratigraphic unit is

required to understand this event. Three map units, Bt-Hbl TTG gneiss, amphibolite-

pegmatite unit and the heterogeneous polyphase gneiss all contain structural elements

inferred to have formed during Dn (Table 1) including;

a) compositional banding and gneissosity within the Bt-Hbl TTG gneiss (Appendix

1A)

b) an earlier phase of leucosome development subsequently deformed into a

crenulation fabric during Dn+1 (Fig. 6C)

c) compositional banding, gneissose fabric development in TTG orthogneiss, early

migmatite generation, mafic intrusion, subsequent fabric development in these

mafic bodies and at least one phase of tight to isoclinal folding effecting entire

heterogeneous package (Appendix 1E).

Dn+1: Post-Assembly

The Dn+1 event is inferred to have proceeded after structural interleaving of the main

tectonostratigraphic package in the Aputitooq mountain map area. Structural evidence for the

19


Early Recumbent Mesoscale Foldingin regional Aputitooq Mtn SynformHinge Zone



E

NWNW SESE

Mafic AmphiboliteMafic Amphibolite

Banded OrthogneissBanded OrthogneissBanded Orthogneiss

Antiformal Hinge ZoneAntiformal Hinge ZoneAntiformal Hinge Zone

F

Recumbent Foldingin Mafic Amphibolite(Antiform Hinge Zone)



G

Complex Recumbent Foldingof Mafic Amphibolite -PegmatiteUnit (U-Pb site - Pegmatite)



H

Top to eastbreak-thrustdevelopment



D

Mafic AmphiboliteMafic Amphibolite

Pegmatitic GranitePegmatitic GranitePegmatitic Granite

A

Recumbent Folding-Mafic AmphiboliteRecumbent Folding-Mafic AmphiboliteRecumbent Folding-Mafic Amphibolite

B

Crenulated EarlierLeucosomal Fabric,Mafic Amphibolite



C

South-plunging open small-scaleparasitic fold, geometrically relatedto regional Aputitooq Mtn synform



I

Figure 6: (A), (B) (C)(D) (E -H) (I)

Important structural attributes associated with the Aputitooq Mountain synform. Early generation overturned recumbent isoclinal folding and related thrusting. Crenulated fabric in fold hinge of recumbentfold. Fabric predates recumbent folding. Thrust development in orthogneiss package. Recumbent fold structures preserved in core of regional synform and antiform structures in Aputitooq Mountain map area. OpenSE-plunging minor fold parasitic to regional Aputitooq mountain synform. Locally refolds isoclinal recumbent structures.

20


event includes mesoscale, overturned to recumbent isoclinal folds and associated breakthrust

development and is best-preserved in the hinge zones of regional Dn+2 folds (Fig. 6A-H).

These foldsets are typically discontinuous, have amplitudes of 1 to 15m, subhorizontal to

shallowly inclined axial planes and locally are bounded on their margins by syn-tectonic

higher strain deformational and/or compositions banding. Syn- and post-tectonic pegmatite

intrusions provide relative age constraints on this phase of deformation in the amphibolite-

pegmatite map unit. Figure 6A-C illustrates that at least one phase of pegmatite intrusion

predates the Dn+1 folding episode and a sample has been collected to constrain the

maximum age of Dn+1. Importantly, these Dn+1 structures can be traced across the

tectonostratigraphy in the map area (Fig. 6D, E; Appendix 1E).

Dn+2 – Brittle-ductile reworking

Dn+2 is attributed to a regional phase of NE-SW compression that produced

macroscale, open and shallowly SE plunging foldsets and associated parasitic folds (Figs.

3D, 4, 6I and 7). This open folding event affected all map units, but was not associated with a

high-grade thermal event. Geometrically related mineral lineations were not observed and

high-grade metamorphic fabrics predate Dn+2 structures.

Dn+3 – Brittle-ductile reworking

Dn+3 resulted in ubiquitous mesoscopic dilatational mini - shears which were

observed to crosscut the main deformational fabrics in the map area (Fig. 6J-M). Small-

volume granitic intrusions are associated with the shearing event. The regional significance

of this event is unclear and geochronology of the dilatational melt will help constrain the age

21


N PO

P

Late BrittleAmph-Bt filledfracture sets



SWSW NENE

Amph-Chl+/-Qtz filledbrittle fracturesAmph-Chl+/-Qtz filledbrittle fracturesAmph-Chl+/-Qtz filledbrittle fractures

J L MK

L

Brittle-DuctileDilatational

Shears and syn-shearmelt injection





GraniticmeltGraniticmeltGraniticmelt


Sinistral shear senseSinistral shear senseSinistral shear sense


Bt-granodioriticorthogneissBt-granodioriticorthogneissBt-granodioriticorthogneiss

Bt-Hbl TTG orthogneissBt-Hbl TTG orthogneissBt-Hbl TTG orthogneissBt-Hbl TTG orthogneissBt-Hbl TTG orthogneissBt-Hbl TTG orthogneiss

Figure 6(continued):

(J-M)

(N-P)

Important structuralattributes associatedwith the AputitooqMountain synform.

Brittle-ductilesinistral shear zonesassociated with syn-shear granite intrusion.

Late brittle NW-striking, SE dippingfracture planes infilledwith Amph+Chl+/-Qtz.

Brittle - Ductile Reworking

Brittle Reworking

22

FA: 24 /165o o Lower hemisphere - synform data

N=85 K=100.00 Sigma=1.000 Peak=7.76

1.2 %

2.4 %

3.5 %

4.7 %

5.9 %

7.1 %

8.2 %

9.4 %

Figure 7: Stereonet plot of foliation data around the Aputitooq mountain synform. Equal area net projections.


23


of this event. It must be noted that no timing relationships have been observed between the

regional open SE plunging open folds and these shear zones and, hence, it is possible that

these shears predate the regional folds.

Dn+4 – Brittle reworking

Dn+4 resulted in a late phase of NW striking brittle fracture systems (Fig. 6N-P). The

fractures are typically filled with unfoliated, coarse-grained, Amph+Chl+/-Qtz aggregates.

2.3 METAMORPHISM

Differences in metamorphic grade have been recognized through the tectonostratigraphic

profile in the Aputitooq mountain map area. Key mineral assemblages for each unit are

illustrated in Figure 8 and summarized in Table 2. Important metamorphic breaks occur

between the

(a) low- to mid-amphibolite facies heterogeneous polyphase TTG complex and

the underlying heterogeneous supracrustal package (upper amphibolite facies

to locally granulite facies relicts; Fig. 8J-L).

(b) low-mid amphibolite facies Bt-Hbl TTG orthogneiss (Kapisillik affinity?) and

overlying amphibolite – pegmatite unit (upper amphibolite-facies; grt+melt

bearing amphibolites and supracrustal lenses grt-bt-sill-leucosome).

Metamorphic assemblages in the heterogeneous supracrustal package suggest it has

experienced both the highest grade of metamorphism in the structural pile and also, a

polyphase history (Table 2; Fig. 8). Decompression textures including cordierite rims on

garnet in metapelitic rocks and plagioclase rims of garnet in mafic compositions suggest

24


Minor supracrustalpackage structurallybelow heterogeneouspolyphase Orthogneissunit



Grt-Bt Intermediate GneissGrt-Bt Intermediate GneissGrt-Bt Intermediate GneissE




Plag moats?Plag moats?Plag moats?

Grt-Hbl-Plag Mafic GneissGrt-Hbl-Plag Mafic GneissGrt-Hbl-Plag Mafic GneissF

Grt-Bt-Crd(?) GneissGrt-Bt-Crd(?) GneissGrt-Bt-Crd(?) Gneiss

GrtGrt

Crd?Crd?

Retrogressed Crd ?Retrogressed Crd ?Retrogressed Crd ?




D

Grt-Bt-Sil GneissGrt-Bt-Sil GneissGrt-Bt-Sil Gneiss

Metasedimentary Unitwithin Mafic Amphibolite- Pegmatite.



A

Grt-Bt-Fspar-QtzGneissGrt-Bt-Fspar-QtzGneissGrt-Bt-Fspar-QtzGneiss




B

Grt-Hbl LeucosomeGrt-Hbl LeucosomeGrt-Hbl Leucosome

Hbl-Bt-PlagMafic GneissHbl-Bt-PlagMafic GneissHbl-Bt-PlagMafic Gneiss

Mafic Amphibolite- Pegmatite UnitMafic Amphibolite- Pegmatite UnitMafic Amphibolite- Pegmatite Unit

C

Figure 8: (A, B) (C)(D)

(E, F)

Mid- to upperamphibolite facies Grt-Bt-Sil mineral assemblage in metapelitic rocks within mafic amphibolite-pegmatite unit .Mid amphibolite facies Grt-Hbl-Plag +/- Bt assemblage typical of mafic amphibolite unit. Grt-Bt-Pl+/- Crd metapelite structurally underlyingheterogeneous, polyphase orthogneiss. Intermediate and mafic gneiss that form a thin discontinuous package structurally below the contact with theheterogeneous, polyphase orthogneiss.

25

Grt-Bt-Plag-Qtz+/- SilMetapelitic GneissGrt-Bt-Plag-Qtz+/- SilMetapelitic GneissGrt-Bt-Plag-Qtz+/- SilMetapelitic Gneiss


H

Retrogressed Crd ?Retrogressed Crd ?Retrogressed Crd ?

Crd?Crd?

GrtGrt

Grt-Bt Intermediate Gneiss(+/- Crd rims on Grt)Grt-Bt Intermediate Gneiss(+/- Crd rims on Grt)Grt-Bt Intermediate Gneiss(+/- Crd rims on Grt)

Crd?Crd?

GrtGrt

K

Crd?Crd?

GrtGrt


L


Retrogradereplacement ofGrt by Bt



Intermediate Gneiss(Grt-Hbl-Bt-Plag-Qtz)Intermediate Gneiss(Grt-Hbl-Bt-Plag-Qtz)Intermediate Gneiss(Grt-Hbl-Bt-Plag-Qtz)

I

Younger Grt leucosomenetwork overprinting olderHbl-Bt-Plag Gneiss ?



Gossanous Supracrustal PackageGossanous Supracrustal PackageGossanous Supracrustal PackageG



J

K

Figure 8: (G)(H) (I)

(J-L)

Hbl+Pl mafic gneiss and crosscutting Grt leucosomes. Representative of mafic component of heterogeneous compositional zonedsupracrustal package. Grt+Bt+Sil+Pl+Qtz metapelite associated with heterogeneous compositional zoned supracrustal package. Grt-Hbl-Btintermediate gneiss. Photo illustrates retrograde replacement of Grt. Grt-Bt +/- Crd intermediate gneiss associated with heterogeneous compositionalzoned supracrustal package.


26

Map UnitMap UnitMap Unit AssemblageAssemblage Interpreted FaciesInterpreted FaciesInterpreted Facies

Table 2: Summary of metamorphic characteristics for each map unit in the Aputitooq mountain map area.

Biotite-Hornblende

HeterogeneousAmphibolite-

Pegmatite

Biotite-Bearing

HeterogeneousSupracrustal Package

Polyphase HeterogeneousTTG Gneiss Complex

Weakly Deformed Granite

Anorthosite Complex

Intermediate CompositionHeterogeneous Gneiss-

Amphibolite

Grt-Pl-Bt +/- Hbl +/- Qtz

Bt-Qtz-Pl-Kfs - n.b. Represents magmatic assemblage;

Intrusion potentially postdates thermal peak

Mafic components: Hbl-Bt-Pl+/- Qtz No Grt observed

Felsic: Qtz-Kfs-Pl-Bt+/- Hbl

Intermediate: Grt-Hbl-Bt-Qtz-Kfs-Pl

Pelitic: Grt-Bt-Qtz (Garnetite) to Grt-Bt-Pl-Qtz;

Grt-Bt-Pl-Qtz+/-Sil

Grt-Crd-Bt-Pl-Qtz+/Kfs

Mafic: Bt-Hbl-Pl-Qtz +/- leucosome (15%);

Grt-Hbl-Bt-Pl+/- Grt-bearing leucosome (15%).

Hbl - Bt - Pl +/- Ep (Grt-absent assemblages)

Grt - Hbl - Bt - Pl+/- Melt

Grt - Hbl - Bt Pl Qtz +/- Melt (intermediate compositions)

Bt-Pl-Qtz-Kfs-Melt [+/-Grt adjacent to contact with supracrustals]

Amphibolite: Hbl - Bt - Pl +/- Ep (Grt-absent assemblages)

Grt - Hbl - Bt - Pl+/- Melt

Grt - Hbl - Bt Pl Qtz +/- Melt (intermediate

compositions)

Pelite: Grt - Bt - Sil - Pl Qtz

Grt Bt Pl Qtz (Sil-absent assemblages)

Mafic: Bt-Hbl-Pl+/Qtz [+/-Chl]

Metapelite: Grt-Bt-Pl-Qtz- [+/- Ms]

(Melt: Grt+Pl+Qtz+Kfs+Bt; Appendix 1A H-K)

Orthogneiss is predominantly Grt-absent; No Sil observed inmetapelite

Mid-upperAmphibolite

Facies


Facies

LowerAmphibolite

Facies

UpperAmphibolite to

Granulite Facies

�

�

�

�

Evidence for polymetamorphismRetrogression from Granulite faciesConditions.Decompression textures (Fig. 8G-L)Crosscutting Grt-bearing leucosomes


Facies

Opx retrogression to Hbl NOTobserved


Facies

Low- to Mid-Amphibolite

Facies

Evidence for polymetamorphism(Fig. 6C)

Key FeatureKey FeatureKey Feature


27


decompression from the thermal peak (Fig. 8). Equivalent decompression textures have not

been observed in other tectonostratigraphic units. Additionally, mafic gneiss horizons within

the supracrustal package unit locally preserves evidence for a grt-bearing leucosome that

post-dates the main metamorphic fabric, further indicating a complex polymetamorphic

history (Fig. 8). A thorough petrographic examination is required to confirm these

observations, however on the basis of mineral assemblages identified in the field, it is

proposed that the different tectonostratigraphic units have contrasting metamorphic histories.

3.0 ECONOMIC GEOLOGY

With regard to economic geology of the the Aputitooq mountain area, the

heterogeneous supracrustal package has the most prospectivity. The unit is variably

gossanous and locally mineralized along its strike length, particularly along contacts between

mafic and pelitic horizons (Fig. 9). Mineralization was observed at one locality

(2006vbe022), within the unit and accompanied by low-grade Ep+Qtz+Chl alteration

adjacent to the mineralized zone. A late, brittle SW trending shear zone is associated with the

showing, in addition to a set of epidote-filled fracture sets. The locality warrants further

examination to further assess the mineral showing (Fig. 9)

4.0 SPECULATIONS AND OUTSTANDING PROBLEM AREAS

Lithological, structural and metamorphic differences that characterize the

tectonostratigraphic package of Aputitooq mountain map area suggest vertical stacking of

different tectonic terranes. The lowermost Bt-Hbl TTG orthogneiss is tentatively correlated

with the Kapisillik terrane based on continuity of the map unit to dated outcrops in the NE of

28

A

Large Gossan - Supracrustal PackageSouth limb, Aputitooq SynformLarge Gossan - Supracrustal PackageSouth limb, Aputitooq SynformLarge Gossan - Supracrustal PackageSouth limb, Aputitooq Synform

Location - 2006vbe024Location - 2006vbe024Location - 2006vbe024

B DC

GFE

Mineral showing,South limb, Aputitooq

Mtn synform(2006vbe22)





EpidoteEpidote

Chl+QtzChl+Qtz

Alteration mineralassemblage associatedwith showing



Epidote + QtzveiningEpidote + QtzveiningEpidote + Qtzveining

Chl+QtzChl+Qtz




Epidote + QtzveiningEpidote + QtzveiningEpidote + Qtzveining

Showing locality,focussed along shearplane and associated withQtz+Epidote veining



Ep+QtzEp+Qtz

ChlChl

Cp+Py(?)Cp+Py(?)

Ep+Qtz+ChlEp+Qtz+ChlEp+Qtz+Chl

Local sulphide mineralizationLocal sulphide mineralizationLocal sulphide mineralization

Figure 9: (A)(B) (C, D)

(E - G)

Rusty alteration of heterogeneous supracrustal package, south limb of Aputitooq Mtn synform.Orange stained gossan associated with mineral showing, south limb of Aputitooq Mtn synform.

Chl-Ep-Qtz alteration associated with mineral showing, south limb of Aputitooq Mtn synform.Mineral showing, south limb of Aputitooq Mtn synform.


29


the map area. The high-level heterogeneous polyphase orthogneiss complex bears a strong

resemblance to the Itsaq gneiss complex, visited during the course of mapping and may

represent continuation of the Færingehavn terrane. The remaining lithologies were not

correlated to known terranes in the region and all map units require U-Pb geochronology to

determine terrane affinity.

Outstanding problems include:

(a) The continuation of the E-W trending supracrustal package, north of the

anorthosite lense, in the SE corner of the map area (Fig. 3D) remains to be traced

out. Currently the unit cannot be extrapolated to either limb of the regional

synform.

(b) Continuity of the 2006 Map area with previous coastline (Itilleq and Kapisillit

Fjords) mapping remains to be established.

(c) Continuity of the Aputitooq mountain map area with 2006 map areas to the east

(Kuiper and Rink) and south (Hiess and Schmidt).

(d) Further investigation of gossans within the heterogeneous supracrustal package.

5.0 SAMPLING AND PLANNED ANALYTICAL WORK

A detailed U-Pb sampling program accompanied mapping and all major map units,

with the exception of the anorthosite complex and intermediate Grt-Hbl intermediate gneiss –

amphibolite were sampled (Fig. 3B). Samples were collected across important metamorphic

boundaries, in particular where relict high grade assemblages were observed, to assist in

locating metamorphic breaks. The elevated relief in the Aputitooq mountain area has exposed

30


an important vertical section through lithological units with contrasting tectono-metamorphic

histories. U-Pb data will be collected by SHRIMP and LAM-ICPMS to examine age

variations within each sample. Complementary IDTIMS data will follow if high-precision

data is required. Collectively, the field, structural, metamorphic and U-Pb data sets will be

used to assess the role of vertical stacking during terrane accretion. The planned analytical

program will be carried out at MUN, St Johns, Canada and ANU, Australia and resultant data

will be supplied to GEUS, initially in open report format and subsequently (and ideally) as

research papers in a suitable peer-reviewed journal.

31

PART II

Itilleq Fjord, Itsaq Gneiss ComplexSampling, Northwest Kapisillit Map Sheet

(Part of UTM Zone 22NW)

Joe Hiess and Venessa Bennett

PART II

Itilleq Fjord, Itsaq Gneiss ComplexSampling, Northwest Kapisillit Map Sheet



PART II

Itilleq Fjord, Itsaq Gneiss ComplexSampling,



Northwest Kapisillit Map Sheet

September 2006 - Kapisillit Field Report Hiess and Bennett

6.0 Introduction

Bedrock mapping and U-Pb geochronological sampling of the Itsaq Gneiss Complex,

took place out of a helicopter camp located on the western shore of Itilleq fjord from 21st

to 23rd (3 - UTM 22NW 524175 7130672). The main objective for the camp was to

sample and examine in detail the well-exposed localities of the Itsaq Gneiss Complex

along Itilleq fjord, which form part of a Ph.D research project currently being undertaken

by Joe Hiess. A WNW-ESE trending creek transect and an NE-SW trending coastal

transect were carried out (Fig. 10). Appendix I illustrates the compositional diversity of

the Itsaq Gneiss Complex occurring at the U-Pb sample localities.

7.0 Geology

Polyphase Heterogeneous TTG gneiss complex

Polyphase, heterogeneous multiply-deformed, hbl-bt tonalitic to granodioritic

orthogneiss with local migmitization and complexly banded gneissose fabric (Fig. 11;

Appendix 1I). The suite of accessory components includes compositions varying from

ultramafic to granitic (Fig. 11A-G). The dominant TTG component contains cm to m

scale ultramafic rafts of coarse-grained clinopyroxenite mantled by hornblendite rims

(Fig. 11F). Planar, tabular and lensoid mafic intrusions cm to m in thickness represent an

additional subordinate component of the complex with compositions and range from

diorite to gabbro. Discordant relationships with the mafic intrusives and the surrounding

TTG host are occasionally observed. Various generations of pegmatites and aplites

33


50 30’Wo

64 15’No

1 km1 km1 km

B

492229

492230

1 km1 km1 kmCamp Site

U-Pb Geochronology Sample Sites

Map Area 2A

Figure 10: (A)(B)

Itilleq Fjord location map with camp site locality and Itsaq gneiss complex U-Pb geochronology sites marked (modified after Friend Kapisillit compilationmap 2005); Satellite image of Akullersuaq map area. Image extracted from Google Earth. Note JMH U-Pb sites geochronology samples no.s are not shown.C C

34


A

E F G

B DC

Figure 11: (A-G) Compositional and textural variability of polyphase orthogneisses of Itsaq Gneiss complex, Itilleq Fjord.

35


pervasively invade the TTG gneisses (Fig. 11A-C). Pegmatites are, locally, very coarse-

grained (Fig. 12A, C, E).

7.3 Structure

Structural features follow the dominant southerly plunging late Erssa Antiform.

The unit can be broken down to identify two structural gradients coinciding with traverse

lines. Along the river transect to the west-north-west, lineation fabrics show varying

intensity against an otherwise dominant planar fabric (Fig. 13A, B). Variations in

lineation development intensity and the attitude of L-dominated fabric may indicate

passage over regional hinge zone. Ductile, high strain domains S within the domain which is interpreted as a regional hinge

36


A

E F

B

DC

Magneticmetallic bluemineral



Pegmatite dykecrosscuttingItsaq GneissComplex



Large radiating Btgrains in pegmatiteLarge radiating Btgrains in pegmatiteLarge radiating Btgrains in pegmatite

GrtGrt

BtBt

Grt+QtzGrt+Qtz

BtBt

Figure 12: (A-F) Coarse grained pegmatite dykes crosscutting Itsaq Gneiss complex, Itilleq Fjord.

37


A

E

B

DC

Figure 13 (A-E): Penetrative lineation dominated fabric that characterizes structural domain 1.

Sth plungingopen folds (SD1)Sth plungingopen folds (SD1)Sth plungingopen folds (SD1)

Refolded isoclinalfold into south-

plungingopen fold


plungingopen fold


plungingopen fold

Strong linear fabric, SD1Strong linear fabric, SD1Strong linear fabric, SD1

Strong linear fabric, SD1Strong linear fabric, SD1Strong linear fabric, SD1

38


domain associated with the Erssa Antiform. The axial trace of this structure is interpreted

to pass through this domain.

Structural Domain 2 (SD2)

Structural domain 2 is characterized by a transitional boundary with SD1 and

identified by a decrease in the penetrative overprinting of SD1 structural elements, thus

structural features occurring in this domain (that are not associated with SD1) are

interpreted to predate SD1. L


A

B

C

Figure 14 (A-C): Recumbent folding characteristic ofStructural domain 3.

40


7.4 Metamorphism

The complex has experienced at least one phase of mid-amphibolite facies

metamorphism. A prograde metamorphic isograd sequence (Hbl-Bt-Plag; Melt in;

Grt+Melt in; Fig. 15) is preserved across the WNW-ESE trending the river transect

(prograde towards the west). Hornblendite rims mantel coarse grained clinopyroxenite

rafts within the TTG component are interpreted as retrogression features. Migmatisation

has well-developed restite and leucosome with several phases of neosome development.

8.0 Economic mineralization

Several generations of pegmatites crosscutting TTG gneisses often contain

magnetic sulphides (magnetite, bornite?; Fig. 12D) in association with garnet and

epidote, smoky quartz. Other important features associated with these occurrences

include epidotized and heavily oxidized late brittle fractures. Localities include

2006jmh064 and 2006jmh066.

9.0 Planned Laboratory Work

U-Pb dating of tonalitic phases for verification as part of IGC. Dating of

superimposed metamorphic events with in situ dating of orientated samples (Appendix 1I

– D- K, U-Pb sites).

41


A B

DC

Figure 15 (A-D):(C,D)

Metamorphic characteristics of the Itsaq Gneiss complex, Itilleq Fjord. The complex has undergone at least onephase of mid-amphibolite facies metamorphism. Locally, two leucosome generations are preserved suggesting the unit underwentpolymetamorphism.

Hbl+Bt+Plgabbroicphase



Grt-Hbl-Bt-Plgabbroic gneiss



Mafic GneissMafic GneissMafic Gneiss

TonaliticGneissTonaliticGneissTonaliticGneiss

Leucosome 1Leucosome 1Leucosome 1



42

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