  Recently, I showed that the "standard model" of solar system formation is
wrong,yielding the contradiction of terrestrial planets having insufficiently
massive cores, and showed instead the consistency of Eucken's 1944 concept of
planets raining out in the central regions of hot, gaseous protoplanets.
Planets generally consist of concentric shells of matter, but there has been no
adequate geophysical explanation to account for the Earth's non-contiguous
crustal continental rock layer, except by assuming that the Earth in the
distant past was smaller and subsequently expanded. Here, I show that formation
of Earth, from within a Jupiter-like protoplanet, will account for the
compression of the rocky Earth to about 64 percent of its current radius,
yielding a closed, contiguous continental shell with concomitant Earth
expansion commencing upon the subsequent removal of its protoplanetary gaseous
shell. I now propose that Earth expansion progresses, not from spreading at
mid-oceanic ridges as usually assumed, but primarily by the formation of
expansion cracks (often near continental margins) and the in-filling of those
cracks with basalt (produced from volume expansion in the mantle), which is
extruded mainly at mid-oceanic ridges, solidifies and traverses the ocean floor
by gravitational creep to regions of lower gravitational potential energy,
ultimately plunging downward into distant expansion cracks, emulating
subduction. Viewed from that perspective, most of the evidence presented in
support of plate tectonics supports Earth expansion; mantle convection is not
required, and the timescale for Earth expansion is no longer constrained to
about 200 million years, the maximum age of the current ocean floor.
