June 8, 2012
David Pratt’s publication in the year 2000 enumerates multiple problems affecting the theory of plate tectonics and seafloor spreading.
The above schematic of Alaska reveals regions of rock strata that appear to have “accreted” to an original craton. Southern Alaska is composed of fragments in all shapes and sizes, each one telling its own tale. They are all “exotic terranes”, formed at different places and times. How they were transported to their present location, and why some are rotated with respect to adjoining terranes is a mystery.
Some exotic terranes arrived from regions on the other side of the world, while others are from nearby locations. They are each quite different from one another in their characteristics, representing strata from many so-called “geologic ages”. There are deposits from the Quaternary period lying in proximity to those from the Cambrian and Mesozoic periods. Those epochs represent hundreds of millions of years. If the theory of continental movement is correct, then “collisions” between landmasses took place more than a dozen times in Alaska. However, each terrane is not arranged side-by-side with its neighbor, they are intermixed with each other, as the schematic reveals.
Another puzzling aspect to the terrane lithography is that some of it is oceanic crust, while some is continental. Some terranes appear to be from volcanic islands. Others appear to be the remains of continental shelves from South America. Less than one percent of Alaska is thought to be from the “original” North American continent.
In the Journal of Scientific Exploration, Vol. 14, No. 3, pages 307–352, David Pratt took issue with the theory of tectonic displacement of continental and ocean floor structure. As he wrote: “The classical model of thin lithospheric plates moving over a global asthenosphere is shown to be implausible.”
Plate tectonics represents the dominant presumption among geophysicists for Earth’s current configuration. The shapes of the continents, as well as earthquakes and volcanoes, are said to be due to the movement of crustal blocks that move apart from one another in some places, while sliding under (subducting) each other in other places. For example, the mid-ocean ridge is supposed to be where Earth’s crust is being pushed apart by upwelling magma. A “seam” of relatively thin crust allows volcanic processes to erupt, creating new seafloor crust that gradually forces the continents to spread apart.
In other places, such as the coast of North America, the pressure from hardened magma in the mid-ocean ridge eruptions is said to force the seafloor into a subduction zone beneath the continent. As the crust is forced down into the depths under North America, it is melted by the hot magma in a kind of lithospheric recycling system. The water in the rocks supposedly becomes water vapor, causing the magma to rise along the continental boundary, forming plutons that eventually find weak spots in the crust. Those weak spots are where volcanoes form. The theory is used to explain the presence of the many volcanoes along North America’s western edge.
250 million years ago, all the continents are thought to have been consolidated into one large landmass called Pangea. What caused Pangea to fracture into the great “plates” on which the continents ride is not known, although many theories have been presented. It is commonly thought that plate tectonics is a cyclical process, therefore Pangea was not the first time that the continents came together, nor will it be the last.
What are Pratt’s concerns with the current theory of Plate Tectonics?
1. The lithosphere is not a contiguous structure. There are alternating layers that make the separation of the lithosphere from the asthenosphere impossible to determine.
2. Earthquakes and volcanoes are supposed to define plate edges. However, recent oceanic research detected earthquakes at depths that are supposed to have no seismic activity, since the deep oceans are far from plate boundaries.
3. Many plates seem not to even exist. As Pratt describes, the northwest boundary of the Pacific, North American, and Eurasian plates, the southern boundary of the Philippine plate, part of the southern boundary of the Pacific plate, and most of the northern and southern boundaries of the South American plate, are fictitious.
4. The appearance of the “continental fit” is an illusion. Many proposals for how the present day continents fit together leave out important considerations. Overlaps of the continental shelves are passed over, while gaps are given no credence. The reader is referred to pages 7-9 of Pratt’s paper.
5. The assumption that rocks are magnetized when they form, and that they retain that magnetization over eons of time is untenable. Furthermore, it is necessary that they retain the magnetic orientation that existed on Earth at the time of their formation.
6. Rather than India being an island for over 200 million years after it separated from Antarctica, and before it “crashed into” Asia, the evidence is that it has always been part of Asia. India shows no sign of a unique flora and fauna that would suggest hundreds of millions of years as an isolated environment, such as the biota in Australia.
7. Heat flow from the spreading zones in the mid-ocean does not fall off farther from the zone. Instead, there is hardly any variance in temperature distribution from the ridges and the rest of the ocean. This fact contradicts a concentrated flow of magma creating new crust in the seams of the ocean floor.
8. The seafloor spreading theory of magnetic anomalies on the ocean floor has been disproven by drilling cores. The so-called “magnetic bands” on the ocean bottom have been found to be composed of isolated ovals, rather than linear formations.
The theory of Plate tectonics does not consider the Electric Universe. As explained in several previous Picture of the Day articles, Earth was once the scene of devastating electrodynamic forces that raised mountains, emptied ocean basins, and melted continents. It is possible that those events took place within the memory of human civilization on this planet. If that is the case, then there is no need to resort to other theories that require ad hoc addenda whenever new information is discovered.