A CONTRIBUTION TO THE GEOLOGICAL HISTORY OF THE NORTH ATLANTIC REGION

Abstract

There may be said to be two main branches of geological investigations the physical and the biological—not, of course, that these can be regarded as independent or divorced from each other, but to a certain point they can make their contributions independently. For a full history, the physical and the biological changes must be known and their mutual relationship understood. It seems possible, however, that the physical history of the earth is likely to be known in much greater detail than that of the fauna and flora, for the “dry lands,” tenanted as they undoubtedly were by various forms of life, have left behind a record which can be fairly well traced on the physical side but will always refuse to yield up all its secrets on the biological side, since only rarely have the land animals and plants been preserved by a lucky chance in the rocks accumulating at the time of their existence. The permanence of continents and ocean-basins has long been a subject of controversy. Lyell, in his “Principles of Geology,” makes reference to the early ideas of the Mediterranean peoples on this subject, while Lyell himself was of opinion that continents and ocean-basins do change places in the course of ages. This idea was early challenged by both physicists and biologists. The physicists, led by Lord Kelvin, regarded the general framework of the earth as having been fixed in very early times, and Kelvin considered that the oceans and continents may have been mapped out ...