I learned about highly interesting finding by geobiologists Benjamin Johnson and Boswell Wing. There is a popular article with title " Earth Could Have Once Been a Waterworld Covered by a Global Ocean, Study Suggests". The research article with title "Limited Archaean continental emergence reflected in an early Archaean 18O-enriched ocean " is published in Nature Geoscience.
The finding is very interesting from the point of view of TGD based Expanding-Earth model allowing to understand Cambrian Explosion (CE) about .54 billion years ago leading to a sudden mysterious emergence of life in a rather short time scale (13-25 million years).
TGD inspired cosmology predicts that cosmic expansion occurs for various astrophysical objects as relatively rapid jerks rather than smoothly. This allows to understand the paradoxical finding that astrophysical objects participate in cosmic expansion but do not seem to expand themselves. The expansion occurs in jerks in which the value of scale dependent cosmological constant characterizing the system decreases.
The findings give a direct support for the absence of continents before CE. What the researchers did was following.
- The radius of Earth would have expanded by a factor 2 in relatively short time scale from a value near to the radius of recent Mars and led to the formation of continents as the Earth's crust ripped. Multi-celllar life would had evolved in underground oceans shielded from meteoric bombardment and cosmic rays and bursted to the newly formed oceans at the surface.
- The basic prediction of the model is that before CE there were no continents. This also kills the so called Snowball Earth model for the climate before CE.
This picture however poses difficult questions. When and how did the continents emerge? How did life emerge if there were no landmasses so that standard model must be given up?
- The goal was to understand the temperature ancient Earth about 3.2 billion years ago, and the researchers studied what they believed to be a bottom of an ancient sea. The isotope ratio of O16 to O18 decreases with temperature. The researchers constructed the temperature profile of the ancient Earth, and the surprising finding was that there was 3.2 per cent more O18 than expected. This is 4 per cent more than in today's relatively ice-free oceans and much higher than the previous estimates.
- The isotope ratio is sensitive to landmass. The conclusion of researchers is that the unexpectedly low ratio could be due to the lack of landmasses. The Earth's surface could have been wet but there is no need to assume oceans. TGD prediction does not exclude wet surface but just the existence of continents. The high wetness could have been due to the percolation of water from underground oceans preceding the great burst - note that 3.2 billion years is by factor about 6 longer time than .54 billion years.
As already explained, TGD based model for Expanding Earth solving basic mystery of standard cosmology provides an answer to these questions and also to the mystery of Cambrian Explosion.
See the chapter Expanding Earth Model and Pre-Cambrian Evolution of Continents, Climate, and Life or the articlewith the same title.