Who was alfred wegener
He searched out other papers about such continental coincidences. Wegener expanded this “debunked” hypothesis in 1915 into what NASA calls “one of the most influential and controversial books in the history of science: The Origin of Continents and Oceans”. Just as Tharp had to overcome resistance to her ideas, reaction to Wegener’s theory “was almost uniformly hostile, and often exceptionally harsh and scathing”, says an article published by the University of California Museum of Paleontology (UCMP). Heezen, who would eventually come around to accepting Tharp’s analysis, claimed “that it sounded like the ‘debunked’ continental drift hypothesis as proposed by Alfred Wegener in 1912”, says a recent article in Forbes magazine. One of her research partners, geologist Bruce Heezen, rejected her ideas as “girl talk”. It describes how Tharp’s findings were initially disbelieved and even ridiculed. Her work led to the acceptance of the concepts of plate tectonics and continental drift, and a 2016 article about her in Smithsonian Magazine was headlined: “Seeing is believing: How Marie Tharp changed geology forever”. The institute, part of New York’s Columbia University, was celebrating the centenary of the birth of the American geologist and oceanographic cartographer who spent most of her career working at Columbia’s Lamont Geological Observatory.īeginning in the early 1950s, Tharp, who died on 23 August 2006, “created some of the world’s first maps of the ocean floor”, the blog says. The Earth Institute’s State of the Planet blog recently featured a story headlined “8 Surprising Facts About Marie Tharp, Mapmaker Extraordinaire”. 3.75-billion-year-old tree-like organism suggests life branched out earlier than expected.
Who was alfred wegener driver#
Tectonic plates were, until recently, the Earth’s major climate driver.Supervolcanoes: deadly for life, deadly for climate.How ancient ocean life in the Gulf of Mexico escaped mass extinction.Earthly comparison hints at shallow liquid water on Jupiter’s moon.Principles of Physical Geology (1st ed.). "Radioactivity and Earth Movements" (PDF). United States of America: Holt, Rinehart and Winston. Historical perspective, in This dynamic Earth: the story of plate tectonics. Translated from the fourth revised German edition by John Biram. Geologische Rundschau (in German) 3 (4): 276–292. Today geologists say that continents are actually parts of moving tectonic plates that float on the asthenosphere, a layer of partly molten rock. Evidence ĭuring the 1950s, in the mid-atlantic ridge discoveries of sea-floor spreading and magnetic reversal proved that Wegener's theory was real and led to the theory of plate tectonics, though his proposed causes were mistaken. Wegener thought that the forces that moved the continents could be caused by the rotation of the Earth and stellar precession and that same forces made earthquakes and volcanic eruptions.
Others argued that Wegener's theory did not explain the forces that would have been needed to move continents to such great distances. Some critics thought that giant land bridges could explain the similarities among fossils in South America and Africa. However, most Earth scientists and palaeontologists did not believe Wegener's theory and thought it was foolish. His Principles of Physical Geology, ending with a chapter on continental drift, was published in 1944. He proposed in 1931 that the Earth's mantle contained convection cells that dissipated radioactive heat and moved the crust at the surface. The British geologist Arthur Holmes championed the theory of continental drift at a time when it was unfashionable. Although continental drift explained many of Wegener's observations, he could not find scientific evidence to make a complete explanation of how continents move. Wegener said that because they are less dense, continents float on top of the denser rock of the ocean floor, and move across the ocean floor rock. He believed these similarities could be explained only if these geologic features were once part of the same continent. Also, he said that the rock strata in South Africa and Brazil were similar. For example, he said that there were geological similarities between the Appalachian Mountains in North America, and the Scottish Highlands. Wegener used geologic, fossil, and glacial evidence from opposite sides of the Atlantic Ocean to support his theory of continental drift. The first time was by the mapmaker Abraham Ortelius in the 16th century. The theory had been proposed before, more than once.