Think about the planets of our Solar System. Earth, like the other inner planets, consists of rock with a heavy iron-alloy core. The giant outer planets, on the other hand, presumably have rock-plus-alloy interiors, but these are surrounded by great shells of light gases, mainly hydrogen and helium, which are many, many times more massive than the underlying rock-plus-alloy. Now, astronomers are beginning to image distant planetary systems of other stars and they find gas-giants even closer to their star than the Earth is to the Sun.

There have long been mainly two ideas about how the planets of the Solar System formed. In the 1940s and 1950s the idea was discussed about planets “raining out” from inside of giant gaseous protoplanets. But that idea fell out of fashion and scientists began thinking of the primordial matter, not being dense protoplanets, but rather spread out into a very low-density “solar nebula”.

The presently popular idea of low-density planetary formation envisioned that dust would condense at fairly low temperatures, and then gather into progressively larger grains, and become rocks, then planetesimals, and ultimately planets. The gaseous components would just go away in an unspecified manner. But there are really serious problems with this picture.

There are only three processes that are responsible for virtually all major aspects of the compositions, internal structures, and dynamics of the various planets and other objects in the Solar System.

Envision the Earth raining out from within a giant gaseous protoplanet. You would thus be imaging the formation of a planet similar in mass to Jupiter, roughly 300 Earth-masses. What would the Earth be like, surrounded by all that gas? J. Marvin Herndon's calculations show that its rock-plus-alloy kernel would be compressed to about 64% of its present diameter. The surface area of that kernel would be quite similar to the surface area presently occupied by the continents, a closed, continental-rock shell without oceans and without ocean floors. And, it would be surrounded by about 300 Earth-masses of primordial gases, just like Jupiter.

It is known that, at an early time during the formation of the Solar System, the gaseous components of primordial matter were stripped from the inner planets, not just the hydrogen and helium, but even the heavy gases like xenon. Astronomers have observed that very young stars are often quite unstable, erupting with energetic outbursts, shedding matter into space as a super-intense solar wind. Herndon suggests that such violent outbursts from our young Sun stripped the gaseous envelopes from the inner planets.

Stripped of its great Jupiter-like overburden of primordial gases, the compressed Earth would begin to decompress, like a ball that has been squeezed and then released. So, there in nature is a mechanism and a primary energy source for whole-Earth decompression, the stored energy of protoplanetary compression.

The initial whole-Earth decompression is expected to result in a global system of major primary cracks appearing in the rigid crust which persist and are identified as the global, mid-oceanic ridge system. As the Earth subsequently decompresses and swells from within, the deep interior shells may be expected to adjust to changes in radius and curvature by plastic deformation. As the Earth decompresses, the area of the Earth’s rigid surface increases by the formation of secondary decompression cracks often located near the continental margins and presently identified as submarine trenches. These secondary decompression cracks are subsequently in-filled with basalt, extruded from the mid-oceanic ridges, which traverses the ocean floor by gravitational creep, ultimately plunging into secondary decompression cracks. This is Herndon's Whole-Earth Decompression Dynamics, a new theory that that unifies elements of plate tectonics theory and Earth expansion theory into a self-consistent new vision of the behavior of our Earth. One of the consequences is a different energy source for driving geodynamics and a new mechanism for emplacing heat at the base of the crust, producing volcanoes and causing earthquakes.