Panthalassa

Panthalassa or Pantalasa (from Greek: πᾶν ' all' and θάλασσα 'sea') was the enormous global ocean that surrounded the supercontinent Pangea during the end of the Paleozoic period and the beginning of the Mesozoic era. Pangea was the supercontinent from which the current continents later broke away, in the context of the theory of continental drift, of the geophysicist and meteorologist Alfred Wegener.

Geological history

The breakup of Pangea formed the Atlantic Ocean and Arctic Ocean basins and caused the closure of the Tethys basin, creating the Indian Ocean basin.

The term Panthalassa is derived from the Greek, which means "all seas", a name that has been agreed upon to be given to the enormous ocean that surrounded Pangea at the end of the Paleozoic and beginning of the Mesozoic approximately 335 million years ago, when it was It formed Pangea, 175 million years ago, when the supercontinent began to separate into smaller ones with the consequent formation of new seas. It should be said that Pangea was not the only supercontinent, but the last to date. The previous ones were Rodinia, fragmented 750 million years ago, and Pannotia, fragmented 540 million years ago.

During the aforementioned periods, relevant events occurred, such as the so-called "explosion" of marine life in the Cambrian with its corresponding mass extinction, proliferation of invertebrates during the Ordovician, appearance of the first land plants in the Silurian and of reptiles and insects during the Carboniferous; The Paleozoic ends in the Permian period with the formation of Pangea and the mass extinction of 95% of existing species.

Before this occurred the Precambrian supereon. Despite its long duration (from 4,600 to 540 million years ago), there is hardly any fossil evidence of life, probably because most forms had soft bodies that could not fossilize or because they were trapped in primitive rocks that later suffered erosion. or metamorphism and the possible remains were destroyed. In any case, the Precambrian Panthalassa was the primordial broth where life originated. The most accepted scientific studies support the formation of life at a time when our planet's atmosphere was reducing (poor in oxygen) and warm and the composition of the seas was very different from today (see the studies by Oparin and Haldane). Others, however, propose that freezing and meteor impacts were necessary (Stanley Miller). In summary, apart from some proven facts (creation of amino acids under prebiotic conditions, Urey-Miller experiment in 1953), there is no single model and it is not very clear how life appeared on Earth, but it is presumed that the ocean, whatever its composition, played an important role; It is not in vain that the oldest fossil samples are from marine organisms.