Plate tectonics is a philosophy that has influenced all geophysical research since about 1970, and subduction is its key mechanism. Subduction was invented in 1967 by Oliver and Isacks as a way to explain how the Earth's diameter remains constant despite discovery of new seafloor growth along the Mid-Atlantic Ridge that confirmed Alfred Wegener's "continental drift" hypothesis that North and South America broke off from Europe and Africa and drifted westward to form the Atlantic Ocean.
This discovery meant that the Atlantic Ocean is a relatively new addition to the planet and is still growing, constantly adding new surface area. However, this new area also meant the Earth must be expanding unless offset by loss of an equal area somewhere else on the planet in order to maintain the accepted belief of the nebular hypothesis that Earth's diameter was fixed at the time of its creation and has always remained the same.
The Pacific Ocean's great size and its "Ring of Fire" with frequent volcanic and seismic activity was the obvious target area where older Pacific seafloor might be disappearing, and of course that is where Oliver and Isacks "found" it, devising the process now known as "subduction."
Subduction ostensibly keeps Earth's diameter constant by forcing "tectonic plates" to somehow (no plausible mechanism has yet been adduced) be pushed beneath the adjoining continental shields and deep ocean trenches surrounding the Pacific basin, thus compensating for an equal area of new seafloor growth occurring in the Atlantic Ocean basin.
The concept of subduction was adopted by the scientific community very quickly (in less than 5 years), bypassing the usual lengthy scrutiny by skeptics who usually demand exhaustive testing and verification before a fundamental new process is accepted.
For comparison, Alfred Wegener's "continental drift" hypothesis was introduced in 1912, but the idea endured decades of scorn and disbelief and was not generally accepted for 50 years until the "spreading ridge" function of the midocean ridges was discovered in 1963 by Vine and Matthews. This provided the causative mechanism needed to explain formation of the Atlantic Ocean and Wegener's continental drift theory.
As it turned out, this new evidence that Earth "might be" expanding in size means that subduction's rapid acceptance was far too hasty. The decision to adopt it was based on what was believed to be good geophysical evidence, but it was based on faulty interpretation of the data due to faulty basic assumptions. The scientific community also unwisely ignored eloquent arguments by Professor S. Warren Carey, (including Bruce Heezen and others who favored Carey's "Earth Expansion Hypothesis") that new seafloor growth along the Mid-Atlantic Ridge was actually evidence the Earth is expanding.
Further time spent researching, testing and calculating rates of growth against assumed rates of subduction might have avoided this unfortunate decision. And now, after 35 years of the "Plate Tectonics Revolution" that was so widely touted, thousands of scientific papers presently in the literature must be ignored unless the underlying research can be salvaged as the basis for some other conclusion. This hasty "rush to judgment" can only be viewed as a tragic waste of time, talent and treasure.
The story of the scientific research that led to the invention of subduction is very interesting, but it also reveals some very troubling aspects of modern scientific research. Rather than try to recapitulate the story here, we recommend viewers read "The Ocean of Truth" by H. W. Menard [1986, Princeton University Press].
Menard’s book is highly recommended reading for anyone interested in scientific research and the intellectual pursuit of answers to complex and controversial geophysical questions, but it is also a warning to the entire scientific community to re-evaluate even the most fundamental beliefs when new ideas are under investigation—an entirely different (and totally unexpected) factor may be involved.
The participants and their highly competitive search for answers to the riddles of the oceans, as well as professional honors and glory, is ably recounted by Menard, one of the marine geologists closely involved with the research and who was personally acquainted with most of the participating scientists.
This highly readable book shows how interpretation of scientific evidence (Benioff zones, spreading ridges, convection cells, deep-focus earthquakes, earthquake clusters, etc.) was influenced by a preconceived notion of Earth’s creation and a fixed diameter held by the senior scientists who controlled the research effort.
Subduction was a new idea conjured up by intelligent people trying to explain newly-discovered phenomena observed in nature that they did not, and still do not, fully understand. Using the same known facts, albeit incomplete and largely hypothetical, other intelligent persons came to completely different conclusions. The Earth's processes certainly had not changed, so the debate developed into “philosophical differences” devised by the minds of men pending some additional discovery or revelation from Nature that might resolve the issue in favor of either viewpoint.
This profound difference between expansion tectonics (an increasing Earth diameter) and plate tectonics (a fixed Earth diameter) illustrates how mortal men, with big egos and established reputations to protect, become deeply divided by such profound differences of opinion based on flawed or incomplete information. This is the stuff of “heated scientific debate.”
Scientists who now believe new seafloor growth is offset by subduction of an equivalent amount of older seafloor in the Pacific Ocean have been deluded by false assumptions, inattention to fundamental physics, and blind adherence to a fixed-diameter philosophy stemming from Laplace's nebular hypothesis. Menard's comments on page 284 of his "The Ocean of Truth" reflect the prevailing fundamental belief of that period: "There was no question in our discussion about the existence of seafloor spreading, although neither of us was confident about it being at a constant rate. Neither of us believed for a moment in an expanding earth, so we were left with a puzzle." [Emphasis mine.]
Any further argument about subduction would be an exercise in futility because evidence of subduction is so feeble or non-existent. The only real solution at this point in time is for NASA and the NGS to measure the trans-Pacific width of the Pacific Ocean basin as soon as possible and provide an answer to the only questions that matter: Is the Pacific Ocean basin decreasing or increasing in size? Is Earth's diameter increasing or decreasing?
The rigidity of the belief in subduction with so little proof is literally astounding and should be examined by scientists as a troubling defect in the so-called “scientific method” in this age of specialization.
The same is true of other recent “scientific discoveries” that are highly questionable or downright ludicrous. The “Mars Rock” (ALH84001), has no specimen from Mars to compare it with, so what was the rationale for the assumption it came from Mars? If it does contain evidence of life on some other planet, why would it have to be Mars? Wouldn't it be more exciting to think that it came from one of the older planets, such as Neptune?
The “moon rocks” found in Antarctica, have a more prosaic, and more plausible, explanation for their appearance here on Earth. How about the probability that rocks found on the Moon were from the same meteor stream that deposited the sibling meteorite found on the Antarctic ice? The same applies to the Mars Rock but there is no way to prove its origin.
© 1999, St. Clair Enterprises (Page last updated 29 April 2005)