Mars’ volcanoes, Earth’s dinosaurs went extinct at similar time

Mars’ volcanoes, Earth’s dinosaurs went extinct at similar time

New NASA analysis reveals that the enormous Martian defend volcano Arsia Mons produced one new lava circulate at its summit each 1 to three million years in the course of the ultimate peak of exercise. The final volcanic exercise there ceased about 50 million years in the past—across the time of Earth’s Cretaceous-Paleogene extinction, when giant numbers of our planet’s plant and animal species (together with dinosaurs) went extinct.

Situated simply south of Mars’ equator, Arsia Mons is the southernmost member of a trio of broad, gently sloping defend volcanoes collectively often known as Tharsis Montes. Arsia Mons was constructed up over billions of years, although the small print of its lifecycle are nonetheless being labored out. The newest volcanic exercise is assumed to have taken place within the caldera—the bowl-formed melancholy on the prime—the place 29 volcanic vents have been recognized. Till now, it has been troublesome to make a exact estimate of when this volcanic area was lively.

“We estimate that the height exercise for the volcanic area on the summit of Arsia Mons in all probability occurred roughly one hundred fifty million years in the past—the late Jurassic interval on Earth—after which died out across the similar time as Earth’s dinosaurs,” stated Jacob Richardson, a postdoctoral researcher at NASA’s Goddard Area Flight Middle in Greenbelt, Maryland. “It is attainable, although, that the final volcanic vent or two may need been lively prior to now 50 million years, which could be very current in geological phrases.”

Measuring about sixty eight miles (one hundred ten kilometers) throughout, the caldera is deep sufficient to carry the whole quantity of water in Lake Huron, after which some. Analyzing the volcanic options inside the caldera required excessive-decision imaging, which the researchers obtained from the Context Digital camera on NASA’s Mars Reconnaissance Orbiter.

The workforce mapped the boundaries of the lava flows from every of the 29 volcanic vents and decided the stratigraphy, or layering, of the flows. The researchers additionally carried out a way referred to as crater counting—tallying up the variety of craters no less than 330 ft (one hundred meters) in diameter—to estimate the ages of the flows.
Utilizing a brand new pc mannequin developed by Richardson and his colleagues on the College of South Florida, the 2 varieties of info have been mixed to find out the volcanic equal of a batting lineup for Arsia Mons’ 29 vents. The oldest flows date again about 200 million years. The youngest flows in all probability occurred 10 to ninety million years in the past—almost definitely round 50 million years in the past.

The modeling additionally yielded estimates of the quantity flux for every lava move. At their peak about one hundred fifty million years in the past, the vents within the Arsia Mons’ caldera in all probability collectively produced about 1 to eight cubic kilometers of magma each million years, slowly including to the volcano’s measurement.

“Consider it like a sluggish, leaky faucet of magma,” stated Richardson. “Arsia Mons was creating about one volcanic vent each 1 to three million years on the peak, in comparison with one each 10,000 years or so in comparable areas on Earth.”

A greater understanding of when volcanic exercise on Mars passed off is essential as a result of it helps researchers perceive the Purple Planet’s historical past and inside construction.

“A serious objective of the Mars volcanology group is to know the anatomy and lifecycle of the planet’s volcanoes. Mars’ volcanoes present proof for exercise over a bigger time span than these on Earth, however their histories of magma manufacturing is perhaps fairly totally different,” stated Jacob Bleacher, a planetary geologist at Goddard and a co-writer on the research. “This research provides us one other clue about how exercise at Arsia Mons tailed off and the large volcano turned quiet.”

The research is also revealed in Earth and Planetary Science Letters.

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