Science News: ocean freshwater plumes, meteotsunami in the Great Lakes, OSIRIS-Rex‘ final close look at asteroid Bennu, rock art of human figures in Australia

Conceptual illustration showing freshwater plumes at sea. Source: Eric Attias

Recent discoveries about our planet, its rocks, and other “stone” topics

In 2020, the groundbreaking discovery of freshwater beneath the seafloor was made. This leaking of groundwater from a coastal aquifer into the ocean via basalt layers is a key process, providing a water source for people, and supporting sea life such as fish and algae. Researchers have now shown that electromagnetic imaging CSEM can be used to map such freshwater plumes in high-resolution.

Street flooding in Ludington, Michigan, during the Lake Michigan meteotsunami event on April 13, 2018. Photo credit: Debbie Maglothin.On the afternoon of April 13, 2018, a large wave of water surged across Lake Michigan and flooded the shores of beach town of Ludington, Michigan, damaging homes and boat docks, and flooding intake pipes. Scientists reconstructed the event in models and determined this was the first ever documented meteotsunami in the Great Lakes caused by an atmospheric inertia-gravity wave.

This artist's concept shows the planned flight path of NASA's OSIRIS-REx spacecraft during its final flyby of asteroid Bennu, which is scheduled for April o7. Source: NASA/Goddard/University of ArizonaNASA’s OSIRIS-REx mission is on the brink of discovering the extent of the mess among the surface rock and dust it made on asteroid Bennu during last fall’s sample collection event. On April 07, the spacecraft will get one last close encounter with Bennu as it performs a final flyover in a distance of about 2.3 miles (3.7 km).

Young Dakal clan landowner Desmond Lindsay visits this site on his country for the first time. Source: Mimal Land Management Aboriginal Corporation (MLMAC)Rock art of human figures created over thousands of years in Australia’s Arnhem Land has been put through a transformative machine learning study to analyze style changes over the years. Tested were different styles labelled ‘Northern Running figures’, ‘Dynamic figures’, ‘Post Dynamic figures’ and ‘Simple figures with Boomerangs’ to understand how they relate to one another.

(06.04.2021, USA: 04.06.2021)