The Eternal gift of Treasure Island
  Earth of the current day is formed of six or seven continents and 4 or 5 oceans, reckoning on whom you raise. however this wasn’t perpetually the case. Through the course of geological time, the continents “drift” concerning on tectonic plates—large components of Earth’s crust that float on a heated plastic layer of mantle and sporadically crash into each other and break apart. each therefore typically (that is, each many hundred million years or so), the conditions area unit such most or all of the continents move to create one larger ground known as a supercontinent. Notable supercontinents of the past embody continent, Gondwana (or Gondwanaland), and—the mother of all supercontinents—Pangea, that lasted from the first Permian period (roughly 299 million years ago) into the first Jurassic period (roughly two hundred million years ago).

But however can we recognize that continent truly existed? on balance, people at large evolved solely a couple of hundred thousand years agone, therefore nobody was around to witness this structural monstrosity. however did scientists “discover” continent and alternative supercontinents of the past? these days, they'll study the earth science record and use mensuration, unstable surveys, and alternative technologies to construct maps of however the globe checked out numerous points in Earth’s history. Pangea’s existence was initial projected in 1912, however, well before the invention of those tools and therefore the development of the trendy theory of geomorphology.

German specializer AElfred Wegener initial given the conception of continent (meaning “all lands”) together with the primary comprehensive theory of geological phenomenon, the thought that Earth’s continents slowly move relative to at least one another, at a conference in 1912 and later in his book The Origin of Continents and Oceans (1915). sort of a few alternative scientists United Nations agency came before him, like 19th-century German naturalist Alexander von Humboldt, Wegener became affected with the similarity within the coastlines of japanese South America and western continent and puzzled whether or not those lands had once been joined along. someday round the year 1910 he began to think about whether or not all of Earth’s contemporary continents had once shaped one massive mass, or supercontinent, long ago, and had later on broken apart. Wegener’s presentation ran counter to the dominant paradigm of the time, that prompt that giant parts of continents foundered and sank at a lower place the oceans over time.

Wegener noted that the define, the geophysics (rocks and landforms), and therefore the climate belts of japanese South America were like those of the southwestern coast of continent. He additionally argued that fossils of sure plants and animals appeared on each of those continents—and that whereas they were alive these organisms couldn’t have traversed the dimension of the South Atlantic that presently separates the 2 continents. So, logic prompt that South America and continent had once been a part of a similar ground. Wegener terminated that South America and continent (as well as others) had been connected to at least one another, probably through land bridges, some 250 million years agone. He additionally believed that continent had lasted through most of Earth’s history. Wegener relied on the work of Austrian scientist Eduard Suess, United Nations agency (although he was an enormous advocate of the existence of sinking continents) initial developed the conception of Gondwanaland—a supercontinent lasting from 600 million to one hundred eighty million years agone and created of contemporary continent, South America, Australia, India, and Antarctic continent. Suess noticed rock formations in India that compared well in terms older and composition with similar formations across numerous hemisphere continents. Wegener used Seuss’s work to support his own geological phenomenon hypothesis and thought of continent to be the southern 1/2 continent.

Despite having this geologic and earth science proof, Wegener’s theory of geological phenomenon wasn't accepted by the scientific community, as a result of his clarification of the driving forces behind continental movement (which he aforesaid stemmed from the propulsion force that created Earth’s equatorial bulge or the attraction pull of the moon) were refuted. Wegener died in 1930, well before several of his concepts relating to continent and geological phenomenon were clean-handed. alternative scientists, however, like South African scientist Alexander Du Toit, continuing to gather proof in support of geological phenomenon.  Du Toit projected the thought of Laurasia—an ancient supercontinent within the hemisphere that enclosed North America, Europe, and Asia (except earth India)—in his book Our Wandering Continents (1937).

Developments in rock and mineral geological dating, sonar, and geology ultimately clean-handed Wegener. The rock formations of japanese North America, Western Europe, and northwestern continent were later found to own a standard origin, and that they overlapped in time with the presence of continent. Together, these discoveries supported the existence of continent. additionally, proof supporting geological phenomenon mounted throughout the twentieth century, and scientists delineate a mechanism that perceived to justify continental movement by the Sixties, that was folded  into the trendy theory of geomorphology. This mechanism was the method of mantle convection—where heated mantle from Earth’s interior rises to the surface to drive apart tectonic plates in opposite directions. though alleged spreading centers (linear boundaries between branching plates on the bed characterised by rising magma) are shown to exist, a proof of however mantle convection truly works remains elusive to the current day.

Modern earth science has shown that continent did truly exist. In distinction to Wegener’s thinking, however, geologists note that alternative continent-like supercontinents possible preceded Pangea, together with Rodinia (circa one billion years ago) and Pannotia (circa 600 million years ago). Today, Earth’s tectonic plates still move, and their motions area unit slowly transferral the continents along another time. at intervals consequent 250 million years, continent and therefore the Americas can merge with continent to create a supercontinent that approaches Pangean proportions. Such associate episodic assembly of the world’s landmasses has been known as the supercontinent cycle or, in honor of Wegener, the Wegenerian cycle.