Planets do not have to grow continuously. If there is such a thing as an expanding Earth and expanding planets this goes against standard science.
A start/stop expansion cycle is an acceptable proposal for those interested in exploring all the possibilities of why the continental plates appear to fit together on a smaller globe.
A recent proposal by a planetary scientist after a new plate tectonics simulation suggests that in their model the movement of the plates can suddenly start and stop depending on how internally hot a planet is.
Estimates of the early Earth’s temperatures suggest Earth may have begun in a hot stagnant lid mode, evolving into an episodic regime throughout most of the Archaean, before finally passing into a plate tectonic regime. The implication of these results is that, for many cases, plate tectonics may be a phase in planetary evolution between hot and cold stagnant states, rather than an end-member.
... The new timeline suggests that Earth’s plate tectonics is just a midpoint in the planet’s evolution between two stagnant states. Planets with different starting temperatures than Earth’s follow different trajectories, the team found. Colder planets may exhibit plate tectonics throughout their history while hotter planets could go for billions of years without plate tectonics.
A window for plate tectonics in terrestrial planet evolution?
Expansion of planets and moons?
A geodynamicist commenting on the paper proposes this could mean planet Venus (other planets and moons?) might trigger plate tectonics again in their future.
The long delay before full-blown plate tectonics hints that the process could one day begin on currently stagnant planets, says Julian Lowman, a geodynamicist at the University of Toronto who was not involved in the research. “There is a possibility that plate tectonics could start up on Venus if conditions were right,” he says.
Plate tectonics just a stage in Earth’s life cycle
Earth expansion episodes
Hugh Owen through his slow expansion hypothesis and book Atlas of Continental Displacement suggests that our globe suddenly started expanding and triggered the recent plate tectonic break up of Pangea, the last super continent, from around 200 million years ago.
Grace Shephard and colleagues have also studied if there are more agreement between the various tomography models at certain depths of the mantle. They have made discoveries that suggest more paleoseafloor can be found at around 1,000 – 1,400 km beneath the surface than at other depths.
"If these depths are translated to time – and we presuppose that the seafloor sinks into the mantle at a rate of 1 centimeter per year – it could mean that there was a period around 100–140 million years ago that experienced more ocean destruction. However, it could also identify a controversial region in the Earth that is more viscous, or 'sticky,' and causes sinking features to pile up, a bit like a traffic jam. These findings, and the reasons behind, bear critical information about the surface and interior evolution of our planet," explains Shephard.
... Plate reconstruction models generally agree that about 130 million years ago, there was a peak in the amount of subduction happening.
Why did the Earth's ancient oceans disappear? | phys.org
Expanding Earth's life
The Cambrian Explosion or Cambrian Radiation of what seems to be near instant evolution of species and life, said to have occurred around 550 million years ago, suddenly started and stopped within 10 million years. The Cambrian Evolution is a massive problem for Darwin s evolution theories and is known as Darwin’s Dilemma.
The theory of the Cambrian Explosion holds that, beginning some 545 million years ago, an explosion of diversity led to the appearance over a relatively short period of 5 million to 10 million years of a huge number of complex, multi-celled organisms.
Moreover, this burst of animal forms led to most of the major animal groups we know today, that is, every extant Phylum.
It is also postulated that many forms that would rightfully deserve the rank of Phylum appeared in the Cambrian only to rapidly disappear.
The Cambrian Explosion | Fossil Museum
Could the Cambrian Explosion and other rapid evolutionary periods be due to plate tectonics or an expanding planet starting and stopping in repeated cycles?
What are all the possible explanations, processes or mechanics for planets interiors or mantles to get repeatedly warmer and colder?