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The evolution of tectonophysics is closely linked to the history of the continental drift and plate tectonics hypotheses. The continental drift/ Airy-Heiskanen isostasy hypothesis had many flaws and scarce data. The fixist/ Pratt-Hayford isostasy, the contracting Earth and the expanding Earth concepts had many flaws as well.
Continental drift is a highly supported scientific theory, originating in the early 20th century, that Earth's continents move or drift relative to each other over geologic time. [1] The theory of continental drift has since been validated and incorporated into the science of plate tectonics , which studies the movement of the continents as ...
Polflucht (from German, flight from the poles) is a geophysical concept invoked in 1922 by Alfred Wegener to explain his ideas of continental drift.. The pole-flight force is that component of the centrifugal force during the rotation of the Earth that acts tangentially to the Earth's surface.
The expanding Earth or growing Earth was a hypothesis attempting to explain the position and relative movement of continents by increase in the volume of Earth. With the recognition of plate tectonics in 20th century, the idea has been abandoned.
This questioning represented a turning point in the study of the Earth. It was now possible to study the history of the Earth from a scientific perspective without religious preconceptions. With the application of scientific methods to the investigation of the Earth's history, the study of geology could become a distinct field of science.
Drift is often subdivided into unstratified (unsorted) drift (glacial till) that forms moraines and stratified drift (glaciolacustrine and fluvioglacial sediments) that accumulates as stratified and sorted sediments in the form of outwash plains, eskers, kames, varves, and so forth. The term drift clay is a synonym for boulder clay. Both are ...
[25] [26] [27] During this time, Earth's crust cooled enough that rocks and continental plates began to form. Some scientists think because Earth was hotter in the past, [ 28 ] [ 29 ] plate tectonic activity was more vigorous than it is today, resulting in a much greater rate of recycling of crustal material.
The first eon in Earth's history, the Hadean, begins with Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, [34] [35] [36] soon after the formation of Earth's crust and Earth itself.