Clarke, D. Barrie (2019) The Origins of Strongly Peraluminous Granitoid Rocks. The Canadian Mineralogist, 57 (4) 529-550 doi:10.3749/canmin.1800075
| Reference Type | Journal (article/letter/editorial) | ||
|---|---|---|---|
| Title | The Origins of Strongly Peraluminous Granitoid Rocks | ||
| Journal | The Canadian Mineralogist | ||
| Authors | Clarke, D. Barrie | Author | |
| Year | 2019 (July 15) | Volume | 57 |
| Issue | 4 | ||
| Publisher | Mineralogical Association of Canada | ||
| DOI | doi:10.3749/canmin.1800075Search in ResearchGate | ||
| Generate Citation Formats | |||
| Mindat Ref. ID | 65577 | Long-form Identifier | mindat:1:5:65577:0 |
| GUID | 0 | ||
| Full Reference | Clarke, D. Barrie (2019) The Origins of Strongly Peraluminous Granitoid Rocks. The Canadian Mineralogist, 57 (4) 529-550 doi:10.3749/canmin.1800075 | ||
| Plain Text | Clarke, D. Barrie (2019) The Origins of Strongly Peraluminous Granitoid Rocks. The Canadian Mineralogist, 57 (4) 529-550 doi:10.3749/canmin.1800075 | ||
| In | (2019, July) The Canadian Mineralogist Vol. 57 (4) Mineralogical Association of Canada | ||
| Abstract/Notes | Abstract Strongly peraluminous granites (SPAGs), with 1.20 < A/CNK < 1.30, are relatively rare rocks. They contain significant modal abundances of AFM minerals such as Bt-Ms-Crd-Grt-And-Toz-Tur-Spl-Crn of potentially magmatic, peritectic, restitic, and xenocrystic origin. Determining the origin of a SPAG depends to a large extent on establishing the correct origin of these AFM minerals. Strongly peraluminous granitic rocks can form in eight distinctly different ways: (1) as the melt fraction resulting from dehydration partial melting of peraluminous metasedimentary rocks; (2) as the bulk composition of diatexitic migmatite resulting from extensive partial melting of peraluminous metasedimentary rock; (3) as a diatexite modified by incomplete restite unmixing; (4) by bulk contamination of a less strongly peraluminous granite magma with highly peraluminous metasedimentary rocks; (5) by selective acquisition or concentration of AFM minerals by a less strongly peraluminous granite magma; (6) by fractional crystallization of quartz and feldspar from a less strongly peraluminous granite magma; (7) by removal of alkalies (Ca, Na, K) by release of a suprasolidus aqueous fluid from a less strongly peraluminous granite magma; and (8) by subsolidus hydrothermal alteration of a less strongly peraluminous granite rock. Contamination by pelitic material is the most effective process for creating SPAG plutons. A detailed case study of the South Mountain Batholith shows that its early SPAGs contain high modal abundances of Bt-Crd-Grt, largely of external origin, whereas its later SPAGs contain high modal abundances of Ms-And-Toz, largely the products of fluido-magmatic processes. | ||
See Also
These are possibly similar items as determined by title/reference text matching only.
