Physics alumnus pens most read article in the journal Geology

An article by physics alumnus Prasanna Mahesh Gunawardana (MS in physics 2016) is this month's most read article in Geology, the prime geosciences journal. The article, Correlating mantle cooling with tectonic transitions on early Earth, based on the second chapter of Gunawardana's Monash University PhD dissertation, is coauthored with Gabriele Morra of our Physics and Geosciences units, Priyadarshi Chowdhury, and Peter A. Cawood. The abstract of the paper is given below to whet your appetite. The link to the full article is given above.

Abstract (Correlating mantle cooling with tectonic transitions on early Earth): The dominant tectonic mode operating on early Earth (before ca. 2.5 Ga) remains elusive, with an increasing body of evidence suggesting that non-plate tectonic modes were likely more prevalent at that time. Thus, how plate tectonics evolved after that remains contentious. We performed two-dimensional numerical modeling of mantle convection at temperatures appropriate for the Hadean–Archean eons and show that subduction and rift systems may have spontaneously emerged on Earth from an earlier drip-and-rift–dominated tectonic mode in response to the secular cooling of the mantle. This cooling of the mantle was mediated by repeated events of rifting and dripping that likely occurred over a few hundred million years. As the mantle cooled, its effective viscosity and the thickness and strength of the lithosphere increased, which helped establish rigid plates and initiate plate tectonics on Earth.