Lithogeochemistry of Geological Units in the Sirmiq Lake Area

The tables below summarize the lithogeochemical characteristics of geological units in the Sirmiq Lake area. These units are described in the Geological Bulletin covering this territory and in the Quebec Stratigraphic Lexicon. The 202 analyses used here come from samples collected during the Ministère‘s mapping campaign in the summer of 2019. They were selected based on certain criteria, including a sum of major oxides between 98.5% and 101.5% and a loss on ignition (LOI) <3%. These analyses were conducted by the Actlabs laboratory 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 Bureau de la connaissance géoscientifique du Québec (BCGQ) regularly inserts blanks, standards and duplicates. Reference materials represent ~10% of the 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 (INAA). For more information on the analysis and dissolution techniques used, refer to the information available for each sample in SIGÉOM à la carte.

Rare earth element profiles of several units and subunits are grouped together to form envelopes containing the 25th and 75th percentiles of the population. This procedure was chosen to simplify the visualization of a large number of profiles as well as when the profiles of the same unit are similar. The envelopes presented are therefore indicative. Rare earth elements are normalized according to the chondrite values of Palme and O’Neill (2004).

 

Intrusive Rocks of the Narsajuaq Lithotectonic Domain

Stratigraphic Unit

Classification

Affinity

Rare Earths

Felsic to Intermediate Intrusive Rocks

Sainte-Hélène Complex (Ashn1)

3 samples

Quartz diorite

(Diagram A and B)

Magnesian, calc-alkaline to calcic and metaluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Sainte-Hélène Complex (Ashn2 and Ashn2a)

10 samples

Tonalite

(Diagram A and B)

Magnesian, generally calcic and metaluminous to peraluminous (type I) granitoid

(Diagram A, B and C)

Profile with negative slope

(Diagram)

Sainte-Hélène Complex (Ashn4)

4 samples

Quartz monzonite and quartz monzodiorite

(Diagrams A and B)

Magnesian, calc-alkaline to alkaline-calcic and metaluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Estre Complex (ApPete1 and ApPete2)

22 samples

Tonalite and granodiorite

(Diagrams A and B)

Magnesian, calcic to calc-alkaline and metaluminous to peraluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Fargues Suite (ApPfag2)

2 samples

Quartz monzonite and quartz syenite

(Diagrams A and B)

Ferriferous, alkaline to alkaline-calcic and metaluminous to peraluminous (type I)

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Fargues Suite (ApPfag3)

3 samples

Monzonite

(Diagrams A and B)

Magnesian, alkaline-calcic to alkaline and metaluminous (type I)

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Navvaataaq Suite (nAnav1)

11 samples

Enderbite

(Diagrams A and B)

Generally magnesian, calcic and metaluminous to peraluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Navvaataaq Suite (nAnav1a)

5 samples

Granite and granodiorite

(Diagrams A and B)

Magnesian to ferriferous, calc-alkaline to calcic and metaluminous to peraluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Frichet Suite (pPfri1)

3 samples

Monzonite and monzodiorite

(Diagrams A and B)

Ferriferous to magnesian, alkaline-calcic and metaluminous (type I) granitoid

(Diagrams A, B and C)

Profile with slight negative slope

(Diagram)

Sanningajualuk Suite (pPsnn1)

6 samples

Granite

(Diagrams A and B)

Ferriferous, alkaline-calcic to calc-alkaline and peraluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Stratigraphic Unit

Classification

Rare Earths

Mafic and Ultramafic Intrusive Rocks

Pingasualuit Complex (nApgs1)

8 samples

Mostly gabbro, gabbronorite and gabbro-diorite

(Diagram)

Profile with slight negative slope

(Diagram)

Pingasualuit Complex (nApgs1a)

9 samples

Mostly gabbro

(Diagram)

Flat profile or with slight negative slope

(Diagram)

Pingasualuit Complex (nApgs1b)

6 samples

Gabbro and monzogabbro

(Diagram)

Flat profile or with slight negative slope

(Diagram)

Pingasualuit Complex (nApgs2)

8 samples

Mostly gabbro-diorite, diorite and quartz diorite

(Diagram)

Profile with negative slope

(Diagram)

Pingasualuit Complex (nApgs3)

12 samples

Gabbro, gabbronorite and ultramafic rocks

(Diagram)

Flat profile

(Diagram)

Pingasualuit Complex (nApgs4)

28 samples

Ultramafic rocks and gabbronorite

(Diagram)

Profile with slight negative slope

(Diagram)

Pingasualuit Complex (nApgs5)

16 samples

Mostly gabbro, gabbro-diorite and monzodiorite

(Diagram)

Profile with negative slope

(Diagram)

Sainte-Hélène Complex (mafic and intermediate layers)

9 samples

Monzogabbro, monzodiorite and gabbro

(Diagram)

Profile with negative slope

(Diagram)

Fargues Suite (ApPfag1)

5 samples

Alkali gabbro and ultramafic rocks

(Diagram)

Profile with negative slope

(Diagram)

Roches intrusives du Domaine lithotectonique de Kovik

Stratigraphic Unit

Classification

Affinity

Rare Earths

Felsic to Intermediate Intrusive Rocks

Gastrin Suite (ApPgan3)

8 samples

Mostly monzonite and monzogabbro

(Diagrams A and B)

Mostly magnesian, alkaline-calcic to calc-alkaline and metaluminous (type I) granitoid

(Diagrams A, B and C)

Profile with slight negative slope

(Diagram)

Gastrin Suite (ApPgan4)

7 samples

Mostly monzonite, monzogabbro and gabbro-diorite

(Diagrams A and B)

Magnesian, calc-alkaline to alkaline-calcic and metaluminous (type I) granitoid

(Diagrams A, B and C)

Profile with negative slope

(Diagram)

Nunataq Suite (pPnat1)

9 samples

Granite and granodiorite

(Diagrams A and B)

Magnesian to ferriferous, mostly calc-alkaline and peraluminous (type I) granitoid

(Diagrams A, B and C)

Profile with steep negative slope

(Diagram)

Stratigraphic Unit

Classification

Rare Earths

Mafic and Ultramafic Intrusive Rocks

Gastrin Suite (ApPgan1)

5 samples

Ultramafic rocks

(Diagrams A and B)

Flat profile or with slight negative slope

(Diagram)

Gastrin Suite (ApPgan2)

3 samples

Gabbro

(Diagrams A and B)

Flat profile or with slight negative slope

(Diagram)

References

Publications of the Government of Québec

VANIER, M. A., LAFRANCE, I. 2020. Géologie de la région du lac Sirmiq, Orogène de l’Ungava, Nunavik, Québec, Canada. MERN. BG 2020-02, 1 plan.

Other Publications

DEBON, F., LEFORT, P. 1983. A chemical-mineralogical classification of common plutonic rocks and associations. Transactions of the Royal Society of Edinburgh, Earth Sciences; volume 73, pages 135-149. doi.org/10.1017/S0263593300010117

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. 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. doi.org/10.1093/petrology/42.11.2033

MANIAR, P.D., PICCOLI, P.M. 1989 – Tectonic discrimination of granitoids. Geological Society of America Bulletin; volume 101, pages 635-643. doi.org/10.1130/0016-7606(1989)101<0635:TDOG>2.3.CO;2

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. doi.org/10.1016/B978-0-08-095975-7.00201-1

 

 

 

13 janvier 2021