A volcano on planet Mars became dormant about the same period when the dinosaurs on Earth went extinct, findings of a new study conducted by NASA researchers suggest.
Arsia Mons Volcano
Scientists think that the volcano was built up over billions of years and that its most recent volcanic activity likely took place in the caldera. Much about the volcano, however, has been unknown and scientists had difficulty making a precise estimate of the time when the volcanic field was active.
A new computer model, however, now sheds light on this and helps scientists find out when the volcano stopped spewing out lava. The computer model revealed that Arsia Mons's volcanic activity stopped about 50 million years ago, which interestingly is also about the same time that the Earth went through the Cretaceous-Paleogene extinction event.
Cretaceous-Paleogene Extinction Event
The global extinction event wiped out three-quarters of the world's plants and animal species, which include the dinosaurs. It is generally believed that the Cretaceous-Paleogene extinction was triggered by a massive asteroid impact and its catastrophic effects albeit some scientists think that the extinction was caused or exacerbated by other factors, which include sea level change, climate change and volcanic eruptions.
Despite the coincidence, study researcher Jacob Richardson, from NASA's Goddard Space Flight Center, and colleagues did not find evidence that directly links the two events.
Arsia Mons's Caldera
Richardson and colleagues identified 29 volcanic vents on Arsia Mons inside the caldera, the cauldron-like depression on top of the volcano which forms when a volcano erupts under its own weight as lava builds up on top. Arsia Mons has a caldera measuring 68 miles across. It is big enough to hold all the waters in Lake Huron, the third largest freshwater lake on Earth.
Determining When The Arsia Mons Was Last Active
Using images taken by the NASA Mars Reconnaissance Orbiter's Context Camera, the researchers mapped the lava flows around the 29 identified volcanic vents in the volcano's caldera.
By tallying the craters around Arsia Mons, the researchers were able to determine the length of time when lava flows had been there. These data also allowed the researchers to estimate the times when the most recent volcanic activity happened, which is between 10 and 90 million years ago. Of the lava flows, the oldest are estimated to be about 200 million years old.
Volcanic Activities On Mars, History And Interior Structure Of Mars
Knowing when the volcanic activity on planet Mars occurred is important since this helps scientists understand the history and interior structure of the Red Planet.
"Magmatism and volcanism have evolved the Martian lithosphere, surface, and climate throughout the history of Mars. Constraining the rates of magma generation and timing of volcanism on the surface clarifies the ways in which magma and volcanic activity have shaped these Martian systems," the researchers wrote in their study.
The findings were published in Earth and Planetary Science Letters.