Oceans are large water bodies found on the earth. Oceans are usually salty in nature and surround the Earth’s continents occupying the basins present in between the continents. Ocean basins represent the part of the sea floor that is usually found lying beyond the margins of the continents. This is mostly in water that is deeper than 600 feet (183 meters). Therefore, this proves that an ocean is basically larger than a sea. All the oceans combined cover almost seventy one percent (71%) of the earth which is approximately 139,400,000 square miles of the entire earth’s surface. The average temperature of the world’s oceans was determined as 3.9 degrees centigrade and the average depth was established as 12,230 feet which translates to 3,730 meters. (Dr. J Floor Anthoni, 2000)
There are four major oceans known in the world to date. These are; The Atlantic ocean, The Arctic ocean, The Indian ocean and the Pacific ocean. These oceans are then all interconnected together and further divided into smaller water bodies to form seas, bays and gulfs all over the world. However, studies reveal that most of the water that flows in our oceans has probably been cycling between the oceans, the land, the seas as well as the earth’s atmosphere for at least more than four billion years. This is basically since the earth was formed. However, this does not mean that no new water gets into the water cycling system. This is because, research shows that as a result of the continuous volcanic activity that takes place up to this day, “ new” water occasionally finds a way to escape from the earths interior and joins the never ending water cycle on the earth.
Before establishing the origin of oceans, it is important to first establish the origin of the ocean floor. The deep basins under the oceans are covered with lava that originally spewed from the sub marine volcanoes found under the oceans.
According to research findings carried out by scientists in California Institute of technology, the origin of the oceans dates back to the time of the formation of the earth. This happened approximately 4.6 million years ago when the planets were being formed, our planet earth being one of them. The earth and all the bodies of the solar system is believed to have been formed through the accretion process whereby, a mass of body increases in size gradually by matter accumulating and adhering to the body. It is believed that the bodies of the solar system are actually surrounded by an accretion disk as a result of the entire accretion process. One of the assumptions stipulates that water came from the rocks that make up the composition of the earth. The other assumption is that water originated from a late-accreting veneer of water- rich meteorites and the last assumptions is that oceans and water bodies arose as a result of a late-accreting veneer of icy planetesimals, for example, comets.
However, all these theories are mere hypotheses and none has been proved to be entirely sufficient. This is because, according to the research carried out on the comets Halley and Hyakutake, it was deemed impossible that comets could have been the source of water in the earth’s oceans. This is because, the ice found to be in comets contains twice the number of atoms of deuterium as compared to each atom of ordinary hydrogen found in sea water. The comets contain large amounts of heavy water which is very rich in deuterium which is an isotope of hydrogen. Therefore if comets were to be determined as the source of terrestrial ocean water, it would only mean that the earth’s ocean water would also be similarly endowed with high deuterium content. However, this is not true (Taylor and Francis, 56).
On the other hand, the meteorites could not have been entirely responsible for all the water found in the oceans because then it would mean that the earth’s atmosphere would be saturated with 10 times the amount of xenon as the meteorites do. Mixing the meteoritic water with cometary water is also not logic since the mixture would contain high concentration of deuterium than is normally found in the oceans.
Therefore, the most likely theory would be the combination of water from comets and water found within the rocky body of the earths crust as it formed. This theory not only solves the xenon problem but also the deuterium problem as well.
However, this is only applicable if and only if the rocky material surrounding the earth’s present orbit picked up some local water from the solar nebula before they accreted to form the present planet earth. This was in order to balance the excess deuterium. The average deuterium/ hydrogen D/H ratios of several sources of water in the solar system were tested and it was determined that the average D/H of Carbonaceous Chondrites (CC’s) is close to the D/H of the earths ocean waters while those of the comets and the nebula are larger than that of the earths oceans. Therefore, the main source of the ocean water was assumed to be CC’s or as earlier said the integration of comets and the solar nebula. However, these results were not conclusive and can only apply if the D/H of water on the earth has remained constant since the accretion of the earth 4.6 million years ago. This outcome suggested that the similarity in D /H of water between the CC’s and the Earth’s oceans currently does not support the CC’s theory of origin of water. However, the discrepancy seen in D /H is not a good enough reason for rejecting the nebular theory of the origin of water.
All in all, the origin of the earths crust is only a theory since rocks dated over 4million years ago studied indicate the presence of ancient seas in very early earth. The ancient oceans are believed to have harbored the first life forms in the planet. Early atmosphere was rich in carbon dixide and it is therefore assumed that these life forms were responsible for the conversion of the carbon dioxide into the present day highly oxygen rich atmosphere. However, it should be noted that years of study has revealed that many processes have taken place transforming the atmosphere into what it is today.
Another scientific theory formulated by scientists was that as the earth was forming from the cloud of gas and dust, a huge amount of lighter elements got trapped inside the molten interior of the planet. As a result, these elemental gases rose through the rocks and erupted on the surface. Once on the surface, the oxygen in the mixture of elements combined with hydrogen that was present in the atmosphere to form the compound, water. At the time, water existed only as an incredibly dense atmosphere of vapor. As a result of the atmospheric cooling process, the vapor condensed resulting in the first raindrops on the earth’s surface (Redfern, 464).
Gradually the process continued hence filling the ocean basins that were present on the earth’s surface resulting in creation of oceans. The idea that the oceans are derived from water and gases originally trapped in the earths rocks can be supported by the fact that studies reveal that meteorites contain roughly 0.5% of water by weight. If this water would be extrapolated into the earth, then it would fill the ocean 20 times and also the fact that a lot of water comes out of volcanoes and could have been enough to fill the ocean basins on the surface of the earth.
However, according to the book Origin of the Oceans by Frank Sherwin, secular scientists try to show that contrary to what was assumed earlier, the waters contained in the present oceans were not of cosmic origin. This simply means that they did not exist in the primordial atmosphere. Instead, the evidence discovered by scientists proves that the water in the present oceans originated from the interior of the earth. This was probably in the first one or two billion years after the process of earth formation was completed. The scientists also went further to analyze the oceanic floor and they discovered that true to what other scientists had said, the new ocean crust had been forming gradually with time as a result of volcanic activity.
Further studies revealed that this process had been going on over the past two hundred (200) million years. This volcanic activity occurred along the mid ocean ridge system and it basically consisted of a series of continuous underwater mountains along the ocean floor spreading. With respect to the present knowledge developed as a result of technological revolution, it seemed highly probable that the water in the oceans and the atmospheric gases had been gradually released as a result of the separation of volatile components. These volatile components were generally from the silicate rocks of the earths crust as well as the upper mantle. All this was as a result of volcanic action on the ocean floor. This theory was supported by the fact that molten lava has over the years been tested and proved to contain large amounts of water as well as other volatiles that usually end to get lost when the lava is solidifying. As time went by, this water that came up as a result of volcanic activity was enough to fill up the ocean depressions hence the formation of oceans.
Geologists who studied this theory were not fully convinced and argued that this was only possible if the process repeatedly happened several times. This was supported by the fact that planetoids were found to still collide with the young earth until 3.9 billion years ago. Planetoids are enormous rocks the size of moons or asteroids. It was further argued that the giant planetoids would have at some point vaporized all the water on the surface of the planet through their impact on collision. However, the earth as it is has undergone so many plate tectonic movements that no traces of its initial appearance can be seen to prove this. However, unlike the earth, the faces of the moon, Mars and Mercury still bear the marks to prove the collisions actually took place. One of the giant craters formed by the impact of planetoids found on the moon is known as Mare Imbrium. This is a large dark ‘eye’ that can be seen on the surface of the moon from anywhere on earth (Brown, 189).
In the mid 1997, a group of scientists formulated a new theory on the source of water in the oceans as well as how the water in the oceans could have possibly gotten their salt from. These scientists were mainly from The National Aeronautics and Space Administrations polar satellite. The group was launched in 1996.these scientists discovered that there were small comets that were roughly 40 feet (12 meters) in diameter that were bombarding the earth’s atmosphere at a rate of almost 43,000 in a day. These small comets disintegrated into icy fragments. This was at heights ranging from about 600 to 15000 miles (960 to 24000 kilometers) above the actual ground. As a result of exposure to sunlight, the fragments vaporized into huge clouds, which consequently would condense into rain as they dropped lower in the atmosphere.This rain was later to be named as cosmic rain. According to scientific calculations, this cosmic rain was responsible of adding at least one inch of water to the earth’s surface within duration of every 10000 to 20000 years. If the process continued, the amount of water could have eventually been substantial enough to fill the oceans. However, this is only possible if these comets had been entering the Earth’s atmosphere since the beginning of accretion 4.5 billion years ago.
Another issue scientists have been trying to explain over the years is the source of salt that is present in ocean water. They base their research on the already formulated theories on origin of oceans. Research has proved that sodium chloride is the most abunndant of all the salts contained in the ocean water. It has always been assumed that the salts present in oceans and seas were mainly as a result of importation from land. This happens after the rocks on land have been dissolved by flowing rivulets and rivers as well as rain water. These rivers and rivulets are usually fed by underground sources as well as dissolved rocks found on the rocks that make up the sea beds and ocean basins. It is a known and proved fact that terrestrial formations are usually rich in the element sodium. It is therefore assumed that the sodium washed out from the rocks on the ocean basin as well as the rocks found around the land supplied its sodium content to the oceans; as the seas on the other hand evaporate, the concentration of these salts increase. However, another problem arose as far as this theory was concerned. Scientists argued that rocks are not usually well endowed with chlorine. Yet, chlorine was necessary in order for Sodium chloride (common salt) to form. Hence, the question of where the chlorine originates from arose. It was later discovered that source water contained traces of chlorine. However, this provided a negligible amount of chlorine and could not be held responsible for the chlorine found in seas and oceans (Morris, 89).
It was therefore assumed that some of the salts could be traced to the erosion of land and the floor of the seas. Moreover, chlorine was known to also have been discharged during volcanic eruptions. Nevertheless, for volcanic eruptions to account for all the chlorine found in the seas and oceans would mean that volcanic eruptions, irrespective of whether on land or under the sea surface, would have to have taken place on an imaginable and very impossible scale. Therefore, the presence of chlorine in the salts of the oceans and seas was still a mystery and a puzzle that was yet to be solved (Chrowder, 335).
During the cataclysm of the Deluge and other cosmic upheavals, volcanoes which were active vomited Sulphur, chlorine and carbonates. This greatly contributed to the composition of salts in the oceans. Carbonates especially fell on the earth in large amounts in several of the upheavals that took place. This was especially evident in the upheaval that took place in the middle of the second millennium just before the present era commenced. However, a major portion of chlorine found in the oceans is so rich that it leaves no doubt that it came from an extra terrestrial source. The final suggestion of atomic free chlorine, seemed both biologically and chemically too complicated to explain and contemplate. This was because chlorine is a very reactive element. Therefore, attempting to seek its ties with other elements would be damaging especially biologically to any plant life.
The origin of oceans can also be viewed from a biblical perspective. According to Genesis chapter one, heaven, and earth together with the seas were created by God all in one swoop. “…..And God said, let the waters under the heaven be gathered together unto one place, and let the dry land appear. And it was so. And God called the dry land earth and the gathering together of the waters was called the seas, and God saw that it was good.” (Genesis, Chapter 1).
The Genesis creation narrative as found in the first two chapters of the Holy bible describes the creation process as it was. It explains a supernatural beginning of the earth and all that is in it. Moreover, it reveals the creativity of God and it describes Him as the overall sole creator of the world and everything in it. In this chapter, God’s action of creation by divine speaking and incantation in six days is clearly described. This brings a whole new perspective of the origin of oceans as it disputes all other theories developed by scientist to try and explain the existence of oceans and the entire world in general. According to Genesis, in the beginning, God was a spirit that was hovering over an empty watery void. This shows that since the beginning, water existed. “…and the spirit of the lord moved upon the face of the waters” (Genesis, chapter 1:2). Therefore much as it can not be proved to be true, it is only best to give this theory some consideration as there is a high possibility of it being true since it is a known and accepted fact that there exists a Supreme Being in the universe.
Another methodology used by people to explain the origin of the sea is the use of myths. Different people who have diverse cultural beliefs have different myths that tally with their religion and culture. For example, the oceanic people believe in the myth that says that all oceans were created by gods. Another myth however states that the oceans were formed by when the sac belonging to the primeval octopus burst open releasing its content hence forming the oceans and seas. According to the Japanese people, the oceans are ruled by not one but several gods. They believe the greatest of the gods ruling the waters is O-Wata-Tsu-Mi, also referred to as Old Man of the Tide. The Chinese also have their own mythology where they believe T’ien Hou, the Empress of Heaven was in charge and responsible for the oceans and all the marine creatures that live in water.
All the above theories and myths are just ways that people have developed to try and answer the questions that usually arise in the day to day life. However, irrespective of the myth or theory put across, one thing is certain and that is that oceans have an immense impact on the lives of mankind and that is the greatest reason why people try to establish its origin. However, it should be noted that oceans just like any other natural phenomena lasts only for a span of time called a life cycle. Once the life cycle is over, the ocean basin ceases to exist. This is because the lithosphere becomes subducted or obducted. Therefore, it is important to realize that oceans do cease to exist at one time.