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Tectonophysics, a branch of geophysics, is the study of the physical processes that underlie tectonic deformation. This includes measurement or calculation of the stress - and strain fields on Earth’s surface and the rheologies of the crust , mantle , lithosphere and asthenosphere .
Map of the later North Atlantic region after the closing of the Iapetus Ocean and the Caledonian/Acadian orogenies (Wilson 1966).Animals: Trilobites and graptolites. [1] [2] Euramerica in the Devonian (416 to 359 Ma) with Baltica, Avalonia (Cabot Fault, Newfoundland and Great Glen Fault, Scotland; cited in Wilson 1962) and Laurentia (Other parts: Iberian Massif and Armorican terrane).
But A. Wegener did not have the specialisation to correctly weight the quality of the geophysical data and the paleontologic data, and its conclusions. Wegener's main interest was meteorology, and he wanted to join the Denmark-Greenland expedition scheduled for mid 1912. So he hurried up to present his Continental Drift hypothesis. [2]
To provide an accessible overview, historians divide human history into different periods organized around key themes, events, or developments that have shaped human societies over time. The number of periods and their time frames depend on the chosen topics, and the transitions between periods are often more fluid than static periodization ...
Called the Anthropocene — and derived from the Greek terms for “human” and “new” — this epoch started sometime between 1950 and 1954, according to the scientists.
Recognizable humans emerged at most 2 million years ago, a vanishingly small period on the geological scale. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago, [ 7 ] [ 8 ] [ 9 ] during the Eoarchean Era, after a geological crust started to solidify following the earlier molten Hadean eon.
In other models, reheating is often considered to mark the start of the electroweak epoch, and some theories, such as warm inflation, avoid a reheating phase entirely. After inflation ended, the universe continued to expand, but at a decelerating rate. About 4 billion years ago the expansion gradually began to speed up again.
One highly debated topic about Earth's interior is mantle plumes. These are theorized to be rising magma, which is responsible for the hotspots in the world, like Hawaii. Originally the theory was that mantle plumes rose up in a direct path, but now there is evidence that the plumes may deflect by small degrees as they rise. [ 7 ]