Description
The geological Eridanos was most important during the Baventian Stage about two million years ago in the late early Pleistocene, when it was about 2700 kilometres or about 1700 miles long, a little shorter than the modern Danube. It began in Lapland, and then flowed through the area of the modern-day Gulf of Bothnia and Baltic Sea to western Europe, where it had an immense delta which, it is reckoned, was comparable in size to that of the current-day Amazon River.
Eridanos deposits in the Netherlands dating from the late Early Pleistocene Menapian glacial stage show the presence of Scandinavian erratic boulders (so-called 'Hattem Layers'; Zandstra, 1971). These erratics are supposed to be transported by fluvial drift ice and are the first indicators in this part of the North Sea Basin of a major glaciation in the Scandinavian mountains. Most probably the reshaping of the Eridanos source areas in the Scandinavian mountains had already started during this glacial stage. During the succeeding Bavel Interglacial the fluvial system reached its largest size but sedimentation rates already dropped at that time. The repeated build up of the Scandinavian ice cap during successive ice ages after this interglacial resulted in a complete destruction of the source area, decapitating the fluvial system, and in the birth of a glacially excavated area surrounding the Scandinavian mountainous areas, in which region the Baltic Sea would later came into existence. During the first glacial stage of the Cromerian Complex, c. 0.7 Ma ago, sedimentation in the Netherlands of the Baltic River System came to an end, indicating the end of the Eridanos.
Remnants of the Eridanos are found all through northern Europe, from the current North Sea and the Netherlands at its western end to sediments in northern Lapland.
Eridanos sediments in the Netherlands and the neighbouring North Sea can be recognized by a high content of transparent blue-grey, lightgrey, and colorless quartz in the sand as well as in the gravel fractions. The color of the mainly coarse sands is grey-white and in the Netherlands these deposits are, therefore, known as the White Sands ('Witte Zanden'). During the Early Pleistocene in the Netherlands fluvial deposits of eastern provenance mix with fluvial deposits of the River Rhine. At that time the Rhine was far less important than the Eridanos. Sediment mixing can be recognized by the presence of a high proportion of 'milky quartz' that is highly characteristic of sands and gravels deposited by the River Rhine. After the disappearance of the Eridanos, the River Rhine is left as the most important river in this part of the North Sea Basin.
Read more about this topic: Eridanos (geology)
Famous quotes containing the word description:
“The next Augustan age will dawn on the other side of the Atlantic. There will, perhaps, be a Thucydides at Boston, a Xenophon at New York, and, in time, a Virgil at Mexico, and a Newton at Peru. At last, some curious traveller from Lima will visit England and give a description of the ruins of St Paul’s, like the editions of Balbec and Palmyra.”
—Horace Walpole (1717–1797)
“Everything to which we concede existence is a posit from the standpoint of a description of the theory-building process, and simultaneously real from the standpoint of the theory that is being built. Nor let us look down on the standpoint of the theory as make-believe; for we can never do better than occupy the standpoint of some theory or other, the best we can muster at the time.”
—Willard Van Orman Quine (b. 1908)
“It [Egypt] has more wonders in it than any other country in the world and provides more works that defy description than any other place.”
—Herodotus (c. 484–424 B.C.)