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Lithogeochemistry of Geological Units in the Lake Conviac Area

The tables below summarize the lithogeochemical characteristics of geological units in the Lake Conviac area. These units are described in the Geological Bulletin covering this territory and in the Stratigraphic Lexicon of Quebec. The 132 analyses used here were obtained from samples collected during the Ministère‘s mapping campaign in the summer of 2021.  They were selected based on certain criteria, including a sum of major oxides between 97% and 103% and a loss on ignition (LOI) <3%. These analyses were conducted by Actlabs in Ancaster, Ontario.

Analyses were subject to an internal and laboratory quality assurance and control process. Thus, to ensure the accuracy and precision of the values provided by the laboratory, the Direction de l’acquisition des connaissances géoscientifiques (DACG) regularly inserts blanks, standards and duplicates. Reference materials represent ~10% of analyses.

The majority of samples in the database were analyzed for major oxides, trace elements and metals. Analyses were performed using different techniques depending on elements, such as inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma optical emission spectrometry (ICP-AES) and neutron activation analysis (INAA). For more information on the analysis and dissolution techniques used, refer to the information available for each sample in SIGÉOM à la carte.

Supracrustal Rocks

Stratigraphic or Lithological Unit

Classification

Affinity

Tectonic Setting

Mg#

Rare Earths

Spider Diagram

Comments

Volcanic Rocks and Associated Lithologies

Natel Formation (nAnt1)
11 samples

Basalt, andesitic basalt and andesite

(Diagrams A and B)

Transitional to calc-alkaline

(Diagrams A and B)

 

Continental arc;

Source: E-MORB with slight crustal contamination

(Diagrams A and B)

 31.25 to 59.78

Profile with slight negative slope for light REEs; flat profile for heavy REEs;

1.83 < (La/Sm)N < 2.75

1.09 < (Gd/Yb)N < 1.90

0.76 < Eu/Eu* < 1.48

(Diagram)

Flat profile with slight positive anomalies in Th and Ta, and weak negative anomalies in Nb, P and Ti

(Diagram)

Selected samples do not show marked alteration.

(Diagrams A and B)

Natel Formation

(nAnt1a)
6 samples

Amphibolite derived from basalt and andesitic basalt

(Diagrams A and B)

Tholeiitic

(Diagrams A and B)

Island and continental arc;

Source: N-MORB with slight crustal contamination

(Diagrams A and B)

 44.20 to 72.96

Flat profile;

1.26 < (La/Yb)N < 2.25

0.99 < (La/Sm)N < 1.68

0.93 < (Gd/Yb)N < 1.90

0.88 < Eu/Eu* < 1.05

(Diagram)

Flat profile with negative anomalies in Nb, Ta and P

(Diagram)

Selected samples do not show marked alteration.

(Diagrams A and B)

Natel Formation (nAnt6)

5 samples

Dacite

(Diagrams A and B)

Calc-alkaline

(Diagrams A and B)

Alkaline arc

(Diagrams A and B)

 26.94 to 44.38

 

Profile with negative slope, lighter around heavy REEs;

15.73 < (La/Yb)N < 30.82

3.65 < (La/Sm)N < 5.34

2.50 < (Gd/Yb)N < 3.55

0.79 < Eu/Eu* < 1.08

(Diagram)

Profile with slight negative slope and negative anomalies in Nb, P, Sm and Ti

(Diagram)

 

Selected samples may show slight sodic alteration.

(Diagrams A and B)

Laguiche Complex
(nAlgi1)

8 samples

Basalt and andesitic basalt

(Diagrams A and B)

Tholeiitic

(Diagrams A and B)

Island arc;

Source: N-MORB with slight crustal contamination

(Diagrams A and B)

 38.99 to 76.88

Flat profile with slight anomalies in Eu;

0.62 < (La/Yb)N < 1.36

0.69 < (La/Sm)N < 1.51

0.64 < (Gd/Yb)N < 0.98

0.61 < Eu/Eu* < 1.38

(Diagram)

Flat profile with slight negative anomalies in Nb and P

(Diagram)

Selected samples do not show marked alteration.

(Diagrams A and B)

Laguiche Complex
(nAlgi5)

6 samples

Amphibolite derived from mafic rocks

(Diagrams A and B)

Transitional to calc-alkaline

(Diagrams A and B)

 

Continental and alkaline arc;

Source: E-MORB with crustal contamination

(Diagrams A and B)

 39.12 to 75.77

Profile with negative slope;

5.33 < (La/Yb)N < 41.27

2.16 < (La/Sm)N < 3.80

1.62 < (Gd/Yb)N < 5.51

0.82 < Eu/Eu* < 1.09

(Diagram)

Relatively evolved profile, generally negative slope, with local negative anomalies in Nb, Ta, P, Hf and Ti

(Diagram)

Selected samples do not show marked alteration.

(Diagrams A and B)

Sedimentary Rocks

Laguiche Complex (nAlgi2a)

19 samples

Slightly migmatized paragneiss derived from graywacke

(Diagrams A and B)

 Does not apply

Active continental margin or island arc margin setting;

(Diagrams A and B)

 

Sedimentary rocks derived from felsic to intermediate sources, not recycled

(Diagrams C and D)

 

36.67 to 52.88

Profile with negative slope for light REEs and flat profile for heavy REEs;

10.49 < (La/Yb)N < 21.83

3.00 < (La/Sm)N < 4.86

1.67 < (Gd/Yb)N < 2.59

0.78 < Eu/Eu* < 1.23

(Diagram)

Profile with slight negative slope;

Negative anomalies in Nb, Ta, P and Ti

(Diagram)

Unaltered sedimentary rocks

(Diagram)

Prosper Formation (nAprp1)

28 samples

Slightly migmatized paragneiss derived from graywacke

(Diagrams A and B)

 Does not apply

Active continental margin or continental island arc setting

(Diagrams A and B)

 

Sedimentary rocks derived from predominantly felsic sources, not recycled

(Diagrams C and D)

 41.23 to 55.91

Profile with negative slope for light REEs and stable to slightly negative slope for heavy REEs, with slight anomalies in Eu;

3.93 < (La/Yb)N < 38.00

1.82 < (La/Sm)N < 6.73

1.38 < (Gd/Yb)N < 2.97

0.66 < Eu/Eu* < 1.41

(Diagram)

Profile with slight negative slope;

Negative anomalies in Nb, Ta, P and Ti

(Diagram)

Slightly altered sedimentary rocks

(Diagram)

Auclair Formation
(nAai1)

4 samples

Non-migmatized paragneiss derived from graywacke

(Diagrams A and B)

 Does not apply

Active continental margin setting

(Diagrams A and B)

 

Sedimentary rocks derived from felsic to intermediate igneous or sedimentary sources, not recycled

(Diagrams C and D)

 36.74 to 48.81

Profile with negative slope for light REEs and flat profile for heavy REEs

14.38 < (La/Yb)N < 23.68

4.25 < (La/Sm)N < 5.48

1.65 < (Gd/Yb)N < 2.14

0.84 < Eu/Eu* < 0.97

(Diagram)

Profile with slight negative slope;

Negative anomalies in Nb, Ta, P and Ti

(Diagram)

Slightly altered sedimentary rocks

(Diagram)

Intrusive Rocks

Stratigraphic or Lithological Unit

Classification

Affinity

Tectonic Setting

Mg#

Rare Earths

Spider Diagram

Comments

Felsic to Intermediate Intrusive Rocks

Village Batholith (nAvil1)

22 samples

Granodiorite and tonalite

(Diagram)

Calcic to calc-alkalic, peraluminous (type I), magnesian to ferroan

(Diagrams A, B, C and D)

Volcanic arc granite

(Diagrams A and B)

 20.39 to 65.72

 

Profile with negative slope and anomalies in Eu. Tonalites are more evolved.

5.93 < (La/Yb)N < 126.87

2.67 < (La/Sm)N < 6.97

0.98 < (Gd/Yb)N < 8.13

0.29 < Eu/Eu* < 1.60

(Diagram)

 

Profile with negative slope and negative anomalies in Nb-Ta-P-Ti; slight negative anomaly in Sm

(Diagram)

Selected samples do not show marked alteration.

(Diagram)

Bauerman Intrusion
(nAbau)

15 samples

Tonalite, monzodiorite, monzonite and granodiorite

(Diagram)

Calc-alkali to alkali-calcic, metaluminous to peraluminous (type I), magnesian

(Diagrams A, B, C and D)

Volcanic arc granite

(Diagrams A and B)

 44.24 to 61.64

 

Profile with negative slope;

7.44 < (La/Yb)N < 45.32

2.38 < (La/Sm)N < 5.54

1.61 < (Gd/Yb)N < 5.67

0.70 < Eu/Eu* < 1.13

(Diagram)

Profile with negative slope and negative anomalies in Nb-Ta-P-Ti, slight negative anomaly in Sm

(Diagram)

Selected samples do not show marked alteration.

(Diagram)

Féron Suite (nAfer2)

3 samples

Diorite, tonalite and monzodiorite

(Diagram)

Calc-alkalic rich in K, metaluminous (type I), magnesian

(Diagrams A, B, C and D)

Volcanic arc granite

(Diagrams A and B)

 46.93 to 57.60

Profile with negative slope;

13.78 < (La/Yb)N < 37.15

3.29 < (La/Sm)N < 6.77

2.11 < (Gd/Yb)N < 3.70

0.83 < Eu/Eu* < 1.07

(Diagram)

Profile with negative slope and negative anomalies in Nb-Ta-P-Ti

(Diagram)

Selected samples do not show marked alteration.

(Diagram)

Kauakiekamatsh Intrusive Suite (nAkkm1)
1 sample
and (nAkkm2)
4 samples

Pegmatitic granite

(Diagram)

Calc-alkalic, peraluminous (type S), ferroan

(Diagrams A, B, C and D)

Volcanic arc to syncollision granite

(Diagrams A and B)

 8.18 to 17.41

Irregular profile, relatively flat, with a significant negative anomaly in Eu;

0.75 < (La/Yb)N < 4.07

1.86 < (La/Sm)N < 3.40

0.30 < (Gd/Yb)N < 0.93

0.09 < Eu/Eu* < 0.21

(Diagram)

Irregular profile, relatively flat;

Marked negative anomaly in Ti, negative anomaly in Nb and positive in Ta. Unit nApcf1 differs from unit nApcf 2 in Ta, La, Ce and P.

(Diagram)

Selected samples do not show marked alteration.

(Diagram)
 
 

References

 

BHATIA, M.R., CROOK, A.A.W., 1986. Trace element characteristics of graywakes and tectonic setting discrimination of sedimentary basins. Contributions to Mineralogy and Petrology; volume 92, pages 181-193. https://doi.org/10.1007/BF00375292

CHAPPELL, B.W., WHITE, A.J.R., 1974. Two contrasting granite types. Pacific Geology; volume 8, pages 173-174.

DE LA ROCHE, H., LETERRIER, J., GRANDCLAUDE, P., MARCHAL, M., 1980. A classification of volcanic and plutonic rocks using R1-R2 diagrams and major element analyses – its relationships with current nomenclature. Chemical Geology; volume 29, pages 183,210. https://doi.org/10.1016/0009-2541(80)90020-0

FROST, B.R., BARNES, C.G., COLLINS, W.J., ARCULUS, R.J., ELLIS, D.J., Frost, C.D., 2001. A geochemical classification for granitic rocks. Journal of Petrology; volume 12, number 11, pages 2033-2048. https://doi.org/10.1093/petrology/42.11.2033

FROST, B.R., FROST, C.D., 2008. On charnockites. Gondwana Research; volume 13, pages 30-44. https://doi.org/10.1016/j.gr.2007.07.006

HARRIS, N.B.W., PEARCE, J.A., TINDLE, A.G., 1986. Geochemical characteristics of collision-zone magmatism. In: Collision tectonics (Coward, M.P., and Reis, A.C., editors). Geological Society, London; Special Publications, volume 19, pages 67,81. https://doi.org/10.1144/GSL.SP.1986.019.01.04

HERRON, M.M., 1988. Geochemical classification of terrigenous sands and shales from core or log data. Journal of Sedimentary Petrology; volume 58, pages 820-829. https://doi.org/10.1306/212F8E77-2B24-11D7-8648000102C1865D

HOLLOCHER, K., ROBINSON, P., WALSH, E., ROBERTS, D., 2012. Geochemistry of amphibolite-facies volcanics and gabbros of the Støren Nappe in extensions west and southwest of Trondheim, western gneiss region, Norway: a key to correlations and paleotectonic settings. American Journal of Science; volume, 312, pages 357-416. https://doi.org/10.2475/04.2012.01

JENSEN, L.S., PYKE, D.R., 1982. Komatiites in the Ontario portion of the Abitibi belt. In: Komatiites (Arndt, N.T. and Nesbitt, E.G., editors). Allen and Unwin, London; pages 147-157.

LARGE, R.R., GEMMELL, J.B., PAULICK, H., HUSTON D.L., 2001. The alteration box plot: a simple approach to understanding the relationship between alteration mineralogy and lithogeochemistry associated with volcanic-hosted massive sulfide deposits. Economic Geology; volume 96, pages 957-971. https://doi.org/10.2113/gsecongeo.96.5.957

MANIAR, P.D., PICCOLI, P.M., 1989. Tectonic discrimination of granitoids. Geological Society of America Bulletin; volume 101, pages 635-643. https://doi.org/10.1130/0016-7606(1989)101%3C0635:TDOG%3E2.3.CO;2

MCDONOUGH, W.F., SUN, S.S., 1995. The composition of the Earth. Chemical Geology; volume 120, pages 223-253. https://doi.org/10.1016/0009-2541(94)00140-4

McLENNAN, S.M., HEMMING, S.R., McDANIEL, D.K., HANSON G.N., 1993. Geochemical approaches to sedimentation, provenance, and tectonics. Geological Society of America; Special Paper 284, pages 21-40. https://doi.org/10.1130/SPE284-p21

NESBITT, H.W., 2003. Petrogenesis of siliciclastic sediments and sedimentary rocks. In: Geochemistry of Sediments and Sedimentary Rocks: Evolutionary Consideration to Mineral Deposit-Forming Environnements (Lentz, D.R., editor). Geological Association of Canada; volume 4, pages 39-51.

OHTA, T., ARAI, H., 2007. Statistical empirical index of chemical weathering in igneous rocks: A new tool for evaluating the degree of weathering. Chemical Geology; volume 240, pages 280-297. https://doi.org/10.1016/j.chemgeo.2007.02.017

PALME, H., O’NEILL, H.S.C., 2004. Cosmochemical estimates of mantle composition. In: Treatise on Geochemistry. (Holland, H.D. and Turrekian, K.K. editors), Elsevier, Amsterdam, The Netherlands; volume 2, pages 1-38. https://doi.org/10.1016/B978-0-08-095975-7.00201-1

PEARCE, J.A., 2008. Geochemical fingerprinting of oceanic basalts with applications to ophiolite classification and the search for Archean oceanic crust. Lithos; volume 100, pages 14-48. https://doi.org/10.1016/j.lithos.2007.06.016

PEARCE, J.A., HARRIS, B.W., TINDLE, A.G., 1984. Trace element discrimination diagram for tectonic interpretation of granitic rocks. Journal of Petrology; volume 25, pages 956-983. dhttps://doi.org/10.1093/petrology/25.4.956

PECCERILLO, A., TAYLOR, S.R., 1976. Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, Northern Turkey. Contributions to Mineralogy and Petrology; volume 58, pages 63-81.https://doi.org/10.1007/BF00384745

PETTIJOHN, F.J, POTTER, P.E., SIEVER, R., 1972. Sand and Sandstones. Springer-Verlag; 618 pages. https://doi.org/10.1007/978-1-4615-9974-6_11

ROSER, B.P., KORSCH, R.J., 1986. Determination of Tectonic Setting of Sandstone-Mudstone Suites Using SiO2 Content and K2O/Na2O Ratio. The Journal of Geology; volume 94, pages 635-650. https://doi.org/10.1086/629071

ROSER, B.P., KORSCH, R.J., 1988. Provenance signatures of sandstone-mudstone suites determined using discriminant function analysis of major-element data. Chemical Geology; volume 67, pages 119-139. https://doi.org/10.1016/0009-2541(88)90010-1

ROSS, P.-S., BÉDARD, J.H., 2009. Magmatic affinity of modern and ancient subalkaline volcanic rocks determined from trace-element discriminant diagrams. Canadian Journal of Earth Science; volume 46, pages 823-839. https://doi.org/10.1139/E09-054

TRÉPANIER, S., 2011. Guide pratique d’utilisation de différentes méthodes de traitement de l’altération et du métasomatisme. Projet CONSOREM 2008-07, 209 pages. Source

WINCHESTER, J.A., FLOYD, P.A., 1977. Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chemical Geology; volume 20, pages 325-343. https://doi.org/10.1016/0009-2541(77)90057-2

 

 

 

18 février 2026
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