Geology and geochemistry of a uranium-rich area in southwestern Newfoundland
A regional geochemical stream sediment survey in southwestern Newfoundland showed several anomalously high uranium areas. Follow-up soil and rock sampling and geological mapping programs were carried out in one of these anomalous areas - the Brinex Lake map-area. -- The area is underlain by granodio...
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| Format: | Thesis |
| Language: | English |
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Memorial University of Newfoundland
1970
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| Online Access: | https://research.library.mun.ca/6817/ https://research.library.mun.ca/6817/1/WilliamRTaylor.pdf https://research.library.mun.ca/6817/3/WilliamRTaylor.pdf |
| Summary: | A regional geochemical stream sediment survey in southwestern Newfoundland showed several anomalously high uranium areas. Follow-up soil and rock sampling and geological mapping programs were carried out in one of these anomalous areas - the Brinex Lake map-area. -- The area is underlain by granodiorite, which is possibly of metasomatic origin, schist and gneisses. Pegmatite dykes are numerous and some aplite and basic dykes were also found. Rocks of the Brinex Lake map-area are possibly of Pre-Cambrian age. -- No uranium mineralization was found in the rocks although some rocks contained anomalously high uranium values, ranging up to 85 ppm. Uranium in the rocks appears to be associated with biotite-rich lenses in schists and gneisses and in the contact zone between them and the granodiorite. Radioactive inclusions in biotite are believed to be the main source of uranium in these rocks. Red hematite alteration, which is characteristic of known uranium occurrences in other parts of the world, is commonly associated with the biotite lenses. Soil and stream sediment anomalies are closely associated with areas containing abundant biotite lenses. -- Comparisons with known uranium provinces suggests that favourable geological environments for the accumulation of uranium into deposits of economic value exist in southwestern Newfoundland. Radioactive occurrences have been reported in similar rocks along the north shore of the St. Lawrence River and in Nova Scotia and New Brunswick. |
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