Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-27T09:43:23.133Z Has data issue: false hasContentIssue false
  • English
  • Français

Zonal dissolution in analcime and pseudomorphs of adularia after analcime from the Lizard, Cornwall

Published online by Cambridge University Press:  05 July 2018

A. F. Seager
A. F. Seager*
Affiliation:
Department of Geology, Birkbeck College, University of London
Get access Rights & Permissions [Opens in a new window]

Summary

Analcime of hydrothermal origin occurs in the gabbros and in the amphibolites and granulites. Crystals from the different rock suites display the same unusual characteristics upon dissolution: the interior is much more susceptible to attack than the outer growth zone; the former may be converted to a skeletal boxwork, and the latter may suffer extreme differential dissolution along successive narrow growth horizons. Pseudomorphs of adularia after analcime have been found in various stages of development, from partial to complete replacement. Some of the latter preserve the very delicate dissolution structures in detail. Up to fourteen growth horizons have been detected in the outer millimetre of the crystal. This demonstrates that both the growth and dissolution of analcime occurred prior to the formation of adularia, an event that has been dated.

Type
Research Article
Information
Mineralogical Magazine , Volume 42 , Issue 322 , June 1978 , pp. 245 - 249
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1978

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Flett, (J. S.), 1946. Geology of the Lizard and Meneage, 2nd edn. Mem. Geol. Surv. G.B.Google Scholar
Green, (D. H.), 1964. J. Geol., 72, 543-63. [M.A. 17-311].CrossRefGoogle Scholar
Halliday, (A. N.) and Mitchell, (J. G.), 1976. Earth Planet. Sci. Letters. 29, 227-37. [M.A. 77-1290].CrossRefGoogle Scholar
Holyer, (V. A. D.), 1972. The Lizard, 4, no. 4, 11-20.Google Scholar
Seager, (A. F.), 1967-8 [1971]. Trans. R. geol. Soc. Cornwall, 20, pt. 2, 97-113 [M.A. 72-3370].Google Scholar
Seager, (A. F.), Fitch, (F. J.), and Miller, (J. A.), 1975. Geol. Mag. 112, 519-22. [M.A. 76-1239].CrossRefGoogle Scholar