Gravity Continues to Shape Earth's Surface From Inside, Study Shows

Gravity is a force drawing bodies together. In the 17th century, British physicist Sir Isaac Newton formulated the theory of universal gravity whereby all bodies are attracted to each other in proportion to their combined mass and in indirect proportion to the distance between them (ie, the heavier and closer they are, the greater the attraction).

A study by researchers in New York shows that gravity continues to shape Earth from within, in much subtler ways than one can imagine.

According to the scientists, deep gravitational pulls and pushes (respectively, centripetal and centrifugal forces) can create some huge motions along faults in the Earth's crust, flattening mountain belts and exposing rocks that had previously been as far as 24km below the surface.

Computer modeling showed that extensional collapse was driven completely by gravity tugging on different densities of material in the covering crust and its boundary with the mantle.

According to the study - 'The role of gravitational body forces in the development of metamorphic core complexes', led by Alireza Bahadori of Columbia and Stony Brook universities in New York - the findings probably "explain many exposures of ancient gneissic domes around the world, where the brittle cover has likely been removed through erosion, exposing the core of the uplifted metamorphic dome".

The study, which appeared in peer-reviewed journal 'Nature', may help to understand the history of the Earth and forecast how the planet's geology might continue to evolve.