In the Indian Ocean , there is an anomaly . The gravity there is lower ( compared to what we ’d expect ) than anywhere else on the planet , and now , a team of investigator may have count on out why .
grant to Newton ’s law of general gravity , objects draw other object with a force determined by their passel and the public square of the aloofness between them . In simple-minded term , the more raft the more gravity , the skinny to the object the more you will be affect by ( and affect ) it .
Though you may think of gravity on Earth as uniform , it is n’t . This is because the mass of the satellite is not evenly distributed like a solid synthetic rubber ball . Instead , we have mountains and trenches , and a whole hatful of other aim andmysterious structuresway below our feet , and bulge out at the equator , induce a varied gravity across the surface .
A gravity map of Earth.Image credit:NASA/JPL/University of Texas Center for Space Research
We acknowledge that gravity dissent across the planet . However , there are areas where gravity differs from what we would await to bump in that field , which is bed as a gravity anomalousness .
One such area is in the Indian Ocean , where the sobriety is lower compared to what we would expect than at anywhere else on Earth . The problem has get scientists for some clip . We know the principles : lower gravity means that mass is missing . However , we did n’t jazz what had get this lack of quite a little .
A team from the Centre for Earth Sciences at the Indian Institute of Science believe they have the resolution . According to the squad ’s paper , which modeled tectonic plate and globular mantle convection over 140 million years , the anomaly may be due to ancient architectonic plates which havesunkdown underneath the Indian Ocean . As a resultant , they believe a plume of spicy mantle – less dense than the sunken incrustation – rose above it .
" period induced by downwelling Tethys slab perturbs the African Large downcast Shear Velocity province and gives rising to plumes that reach the upper mantle , " the team write in their paper . " These plumage , along with the mantle structure in the vicinity of the geoid low , are responsible for the organization of this negative geoid anomaly . "
The paper is published inGeophysical Research Letters .
