Abstract
This essay is not self contained. In brief extracts it is impossible adequately to summarise such papers in ECONOMIC GEOLOGY as those of Moore and Maynard, Gruner, or Gill. It is assumed that the present contribution will be read in conjunction with those papers.The suggestion here advanced is that the banded iron deposits of the older pre-Cambrian throughout the entire world represent epicontinental sediments formed as chemical precipitates from cold natural solutions in isolated closed basins on a land surface that had been reduced to the last limit of peneplanation.Analogies are drawn with the duricrust of Australia, formed on a surface of somewhat less ideally perfect peneplanation during an era of low rainfall with marked seasonal incidence. The exceedingly small probability of repetition of periods of such exceptionally perfect base-leveling is considered to explain the uniqueness in character of deposits of this type.The writer is of opinion that, in most geological literature, exaggerated insistence on marine sedimentation is evidenced. Reasons are given for this view.The necessity for critical consideration of admissibility of results of laboratory experiments in explaining geological processes is discussed.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call