A Questioning Look at Earth Expansion Theory

In 1933, Otto Hilgenberg (1896-1976), well before plate tectonics theory, published a different idea about the continents.

Hilgenberg imagined that initially the Earth was smaller in diameter, without oceans, and that the continents formed a uniform shell of matter covering the entire surface of the planet. Hilgenberg’s idea was that the Earth subsequently expanded, fragmenting the uniform shell of matter into the continents, and creating ocean basins in between. He spent the rest of his life making impressive model globes, including those in the shown in the photo below to the left, writing, and lecturing on the subject. Decades before space vehicles showed that generally the planets of our Solar System are covered by uniform shells of surface matter, that the Earth is the exception, Hilgenberg had the insight to think that the Earth should have had in the past a complete shell of continental rock covering its surface.

Hilgenberg's writings and lectures attracted others, such as S. Warren Carey (1911-2002), who built upon the idea and helped to promote it. S. Warren Carey is shown in the photo at right along with Klaus Vogel, another long-time proponent of Earth expansion theory. Interestingly, Hilgenberg made those globes based upon coastlines, not submerged continental margins. The continental shelves actually yield a better fit and would imply a larger proto-earth (64% of present size instead of 50%), i.e., less expansion required.

Seismic data from earthquakes and nuclear device detonations, as well as data from planetary probes, show that generally planets consist of more or less uniform shells of matter. Interestingly, Hilgenberg's explanation is the only satisfactory explanation yet advanced to explain the non-uniform (continental rock plus oceanic basalt) surface shell of the Earth. But there are some really big problems with classical Earth expansion theory, such as espoused by Carey. 

One big problem is energy: For the Earth to have expanded it would have to do work against gravity and that would take a HUGE amount of energy, more than all of the Earth’s nuclear fuel could have ever have yielded. Such a powerful energy source was unknown. Some scientists even suggested that the expansion came about as a consequence of changing laws of nature, but there is still no independent corroborating evidence.

Another big problem is time scale: The oldest seafloor is only 180 million years old, but the age of the Earth is about 4½ billion years. Earth expansion theory envisions ocean basins being formed as the Earth expanded and thus separated the continents. That would mean, accordingly, that all Earth expansion occurred during the last 200 million years as no seafloor is any older than that. How can that be reasonably explained?

Still another big problem comes from Earth-orbiting satellite data: Modern measurements show that the Earth is presently not expanding. If, according to Earth expansion theory, all expansion took place during the last 200 million years, it would seem strange indeed that there is no present Earth expansion.

Just as in plate tectonics theory, there are appealing aspects to Earth expansion theory, like the origin of continents from a uniform continental shell, but there are also profound difficulties. The fact that decades have passed without reconciliation of these two seemingly disparate scientific theories might suggest that neither is wholly correct. Perhaps ultimately the correct theory lies somewhere between the two. Perhaps the middle-ground is the new theory that J. Marvin Herndon, pictured left, proposed, called Whole-Earth Decompression Dynamics, which unifies certain elements of plate tectonics with certain elements of Earth expansion.