Correspondence: Department of Earth Sciences, Carleton University, Ottawa, Ontario, K15 5B6, Canada.
Analcime in lake and lake-margin sediments of the Carboniferous Rocky Brook Formation, Western Newfoundland, Canada
Article first published online: 14 JUN 2006
Volume 36, Issue 5, pages 875–887, October 1989
How to Cite
GALL, Q. and HYDE, R. (1989), Analcime in lake and lake-margin sediments of the Carboniferous Rocky Brook Formation, Western Newfoundland, Canada. Sedimentology, 36: 875–887. doi: 10.1111/j.1365-3091.1989.tb01751.x
- Issue published online: 14 JUN 2006
- Article first published online: 14 JUN 2006
- Manuscript received 11 October 1988; revision received 19 December 1988
In the Deer Lake Basin of western Newfoundland, Canada, analcime has been found within fine-grained, siliciclastic and carbonate, lake and lake-margin sediments of the Carboniferous Rocky Brook Formation. Analcime is the only zeolite observed in these unmetamorphosed and non-volcanogenic rocks. Microscopic analcime occurs as vug-filling, limpid, isotropic to anisotropic crystals. Microprobe analyses show this type of analcime to be lower in silica than most analcime in sedimentary rocks. A second textural type of finer-grained submicroscopic analcime can be detected from X-ray diffraction spectra of Rocky Brook Formation mudstones, where it is associated with phyllosilicates (illite, interstratified chlorite/smectite, smectite, chlorite), other silicates (quartz, feldspar) and carbonates (dolomite, calcite). Results of this study suggest that the analcime in the Rocky Brook Formation formed either by direct lakewater/porewater precipitation or by reaction of these waters with one or more clay mineral types or plagioclase.