The origin of the ocean can be traced back to four billion years ago when the earth was formed through the accumulation of tiny objects known as the planetesimals (Delsemme, pp. 35). There are two possible sources that are believed to have led to the formation of the ocean. The first one is the extraplanetary sources; it claims that the world’s oceans could have been formed through colliding with the comets, trans-Neptunian objects or protoplanets which are found in the outer reaches of the asteroid belt with the earth (Kevin, et al, pp. 208). After the heating of planetesimals as a result of the decay of the aluminum isotope, the water rose to the earth’s surface. According to the studies that were carried recently, water with the same deuterium to hydrogen quantity was available at the time when the earth was being formed. Another research conducted on the moon to determine its composition shows that by the time the earth was being formed, it had its water (Julio A, et al, pp. 437).
Additionally, water can be stored in hydrated minerals of the earth’s rock. This water is believed to have gradually leaked to form a portion of the earth’s ocean water. Another theory is that water might have also come from volcanism. Volcanic eruptions might have formed water vapor in the atmosphere which might condense later to form rain to fill the earth’s oceanic basins slowly. It is believed that some quantity of water might have been one of the materials that led to the formation of the earth (Julio A, et al, pp. 437). Some terrestrial water is believed to have biochemical origin; this might have taken place during the Great Oxygenation Event through redox reactions and photosynthesis (Armen Y., et al, pp. 825).
Delsemme, A. “The origin of the atmosphere and of the oceans.” Comets and the Origin and Evolution of Life. Springer New York, 2012. 29-67.
Walsh, Kevin J., et al. “A low mass for Mars from Jupiter/’s early gas-driven migration.” Nature 475.7355 (2013): 206-209.
Fernandez, Julio A., and W-H. Ip. “Orbital expansion and resonant trapping during the late accretion stages of the outer planets.” Planetary and space science 44.5 (2014): 431-439.
Mulkidjanian, Armen Y., et al. “Origin of first cells at terrestrial, anoxic geothermal fields.” Proceedings of the National Academy of Sciences 109.14 (2012): E821-E830.
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