BEIJING, Oct. 23 (Xinhuanet) -- Magma plumes that move beneath Mars' crust, suggested by new research on Hawaiian volcanoes, coupled with satellite imagery has researchers postulating Martian volcanoes may not be extinct.
"On Earth, the Hawaiian islands were built from volcanoes that erupted as the Earth's crust slid over a hot spot -- a plume of rising magma," said Jacob Bleacher, a planetary scientist at Arizona State University and NASA's Goddard Space Flight Center in Greenbelt, Md. "Our research raises the possibility that the opposite happens on Mars; a plume might move beneath stationary crust."
Recent images from the European Space Agency's Mars Express missions suggest the volcanoes there have been active within the past two million years and might still be. And sparse impact craters near the three Tharsis volcanoes indicate relatively recent eruptions.
"We thought we could take what we learned about lava flow features on Hawaiian volcanoes and apply it to Martian volcanoes to reveal their history," Bleacher said. But until recently, images of Mars weren't detailed enough to make a good comparison, he noted.
Relying on new images from NASA's Mars Odyssey and Mars Global Surveyor orbiters, as well as the ESA's Mars Express, the team saw the three volcanoes were similar in formation. However, each had recently erupted in distinct ways that allowed the scientists to determine the ages of the eruptions.
During the volcanic activity, lava oozed from cracks in the volcanoes' sides and formed "lava aprons;" the smoother the apron, scientists determined, the older the eruption.
Lava aprons on the northern-most volcano, Ascraeus Mons, are the youngest, Bleacher said, while the southern-most volcano, Arsia Mons, has the oldest. Similar to the Hawaiian volcanoes, the findings show that the volcanoes were fed by a common source of magma-but one that was on the move.