Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-23T16:26:23.402Z Has data issue: false hasContentIssue false

II.—The Principle of Saturation in Petrography: A Reply

Published online by Cambridge University Press:  01 May 2009

S. J. Shand
Affiliation:
Victoria College, Stellenbosch, South Africa.

Extract

In exercising a debater's right to reply to criticism, I shall be extremely brief. My contentions, in two essays on the above subject,1 were as follows:—

1. That the classification of rocks by silica percentage is unsatis-factory, and that a more natural basis for classification is available in the degree of saturation of the constituent minerals.

My critic, Mr. Scott, has not expressed any opinion on this pointof comparison.

2. That the field evidence is overwhelmingly favourable to the separation of the rock minerals into two groups, those of one group being stable in the presence of free silica under magmatic conditions, those of the other group unstable; and that such experimental work as has been done supports that separation.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1915

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

page 339 note 1 Geol. Mag., 11, 1913, p. 508, and 11, 1914, p. 485Google Scholar.

page 339 note 2 Amer. Journ. Sci., 04, 1915.Google Scholar

page 340 note 1 Journ. Amer. Chem. Soc., 1906Google Scholar.