Hostname: page-component-77c89778f8-cnmwb Total loading time: 0 Render date: 2024-07-18T17:21:40.878Z Has data issue: false hasContentIssue false
  • English
  • Français

IV.—“How Long Ago” in Geology

Published online by Cambridge University Press:  01 May 2009

Edward A. Martin
Get access Rights & Permissions [Opens in a new window]

Extract

One is frequently asked the question, how long ago is it since certain geological phenomena took place in which the questioner is interested for the time being. How long ago were the great coal-beds deposited, or how long ago is it since the chalk was formed at the bottom of the sea?

Type
Original Articles
Information
Geological Magazine , Volume 4 , Issue 8 , August 1907 , pp. 349 - 351
Copyright
Copyright © Cambridge University Press 1907

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

1 The principal unconformities have been considered and estimated for by the late Mr. J. G. Goodchild in his “Evidence regarding the Age of the Earth” (See Review in Geol. Mag., 1897, pp. 415—417), Edinburgh, McFarlane & Erskine, 1897, and Proc. Roy. Phys. Soc. Edinburgh, vol. xiii, pp. 260–303.

2 Mr. Goodchild liberally allows 70,200,000 years for three well-recognised breaks in his geological series, and for the whole period of geological time he suggests 704,235,000 years.