Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-26T21:17:07.508Z Has data issue: false hasContentIssue false

III.—On a Case in which various massive Crystalline Rocks including Soda-Granite, Quartz-Diorite, Norite, Hornblendite, Pyroxenite, and different Chrysolitic Rocks, were made through Metamorphic Agencies in one Metamorphic Process

Published online by Cambridge University Press:  01 May 2009

James D. Dana
Affiliation:
Memb. Geol. Soc. Lond., Yale College, New Hawen, Ct., U.S.A.

Extract

The above brief description of the Cortland rocks prepares the way for a consideration of their relation to the other rocks of the county. The following questions arise: Are they one with the latter in system ? are they rocks of an earlier system ? or are they eruptive rocks, and not metamorphic, and hence, of no bearing on the general question as to the age of the Westchester limestones and the associated schists ?

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1881

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 113 note 1 In the writer's Manual of Geology (1880), veins of this kind are called veins of plastic injection, an abbreviation of the full statement that they were made by the injection of material rendered plastic or fused during a process of metamorphism. They are better called dyke-like veins.

page 114 note 1 The term supercrust is used for that part of the earth's crust which has heen made by sedimentation, the true crust being restricted to the part beneath which is a result simply of cooling.