Time Schedule Based On Ocean Wa
Time Schedule Based on Ocean Water
As noted, geologists concluded that the chemical composition of sea water and the ocean floor sediments is principally a product of the weathering of continental rocks. If this weathering of rocks was a very short time phenomenon, then one would expect to find far different proportions of elements in sea water than are found within the average rocks of the continents.
This seems logical since some rocks erode more easily than others, and therefore easily erodable chemicals should be most abundant in sea water. Differences in relative chemical proportions would also be due to other variables, such as the fact that some elements are not as readily transportable by rivers and ocean currents as others, and some are less soluble in water than others.
Nevertheless, if the duration of erosion was long enough, elements in the sea water and on the sea floor should quite accurately coincide with the chemical content of continental masses. Even the hardest of rocks would be eroded, and even the least transportable of minerals would ultimately be carried by the rivers to the sea.
Thus when scientists talk about millions of years, on a world-wide basis, the proportion of one element in the sea water and on the sea floor to all other elements in the same environment should be approximately the same ratio as that element to all other elements in the continental masses, for in a very general way all the mass must shomhow be conserved. For example, if the percentage of silicon in the continental masses is 27.5%, then if the oceans were old enough, the total of all the silicon in the ocean water and on the ocean floor should be 27.5% approximatey.
Furthermore, if the total quantities of various elements in the seas and sea floor and the approximate rate of world-wide erosion could be known, then the length of time required to bring present elements into the ocean could be estimated. In turn, an approximate age for the earth might be deduced.
Fortunately, scientists have determined rather accurately the chemical composition of both the sea water and the land masses. Sverdrup et al prepared a table (Table I)(5) showing the amounts of various chemicals that should have entered the oceans during a period of 260 millions of years. This is the estimated length of time which would be required to provide the present quantity of salt in the ocean water, assuming uniform weathering throughout this period of time.
He mentions an estimate by Goldschmidt in 1933 that accumulation of the present concentration of salt (NaCl) in solution would have required weathering of 600 grams of rock for each kilogram of water in the ocean. Thus according to Table I, 17,000 mg. (17 gr.) of sodium were released and 165,000 mg. (165 gr.) of silicon were likewise released for accumulation in the oceans for each 600 grams of rock weathered.
With this estimate of potential elements available, one wonders what is the actual quantity of elements in sea water. An estimate for each element is given in the second column of Table I.
For example, in a kilogram of sea water there is on the average about .5 mg. of aluminum in solution. This is only .001% of the estimated 53,000 mg. expected if weathering had continued for as long as 260 million years, the estimated time required to provide the observed amount of salt.
In fact, after close examination of all the elements listed in Table I, one concludes there is a total lack of relationship between the chemicals in the oceans and the continents. For example, chlorine is 67 times too prevalent in sea water, nickel is 500,000 times too scarce. Silicon, which is one of the most common constituents of rocks, should be 50,000 times more plentiful in ocean water if it were in proportion to that in continental rocks.
Perhaps one reason for this total disproportion between the expected volumes of elements in the sea water and their actual occurrence is that sea water will hold in solution only a tiny bit of each element. In other words, most of the silicon goes out of solution to the sea bottom either by precipitation or by the action of organisms. That sea water is not saturated with silicon is supported by F.A.J. Armstrong:
Sea water is undersaturated with respect to silica, although since reported values for its solubility are somewhat inconsistent, it is not possible to say how much.(6)
And Kuenen has written:
Under normal conditions sea water is not supersaturated with any product, and circulation is automatically set up in areas of excess evaporation, preventing the formation of excessive concentrations.(7)
Apparently, then, many elements are far too insufficient in ocean water as compared with the quantities that should be present if the oceans were millions of years old. And further, the sea water in general is not saturated with chemical elements.
Therefore the oceans could be very young, because if the oceans had existed long enough, those elements which are especially soluble would have reached a saturated condition in many parts of the world.
Using the unsaturated condition of the oceans, researchers should be able to measure the age of oceans since an estimate can be made of the average annual quantity of chemicals flowing into the ocean from the rivers. Dividing the total quantity of an element existing in an unsaturated condition in ocean solution by the quantity of the same element flowing into the ocean should result in some concept of the ocean’s age.
This information is found in Table II.(8) Evidently 2.0 x 10^7 (20 million) years of continental weathering would have been required to supply all the lithium (Li) presently found in ocean solution. Presumably, sodium (Na) would have been accumulating for some 2.6 x 10^8 (260 million) years.
Nevertheless, a very strange fact becomes evident upon careful study of Table II. Some of the elements are in very short supply in the oceans. Therefore only 100 years of continental weathering would have been required for accumulation of the tiny quantity of aluminum in ocean solution. In fact, nineteen of the elements in sea water are found in such small amounts that the concentrations could have accumulated in 1,000 years of continental weathering. Two conclusions are possible from this startling information:
l. The oceans must be very young because small quantities of many of the elements are in solution.
2. The oceans must be very young because of the wide discrepancy of residency periods of various chemicals. Differential erosion over a relatively short period of time together with other variables, such as water transportability and solubility of elements, could account for this wide spread in residency times.
One other fact should be noted in this regard. Chlorine, sulphur, bromine and boron exist in much larger amounts (See Table I) than those which would be supplied while the elements, such as sodium, with which they are normally associated, were being weathered from rocks into the ocean waters. Therefore a third conclusion is possible:
3. That salt (NaCl) and perhaps a number of other chemicals are in the oceans completely apart from normal rock weathering.