Mars might not be dead, geologically speaking.
Researchers have examined a variety of Marsquakes that have occurred recently on the Red Planet. They found that they are likely to be caused by volcanic activity. magma moving beneath the Martian surface. That’s evidence that Mars is still volcanically active, the researchers report October 27 in Astronomy of Nature.
Since Four years ago, Mars was touched down, NASA’s InSight lander has detected more than 1,000 Marsquakes (SN: 11/26/18). Its seismometer records seismic waves, which reveal information about a temblor’s size and location.
Studies in the past have shown that many Marsquakes originated in Mars. A swathe of Martian terrain called Cerberus Fossae (SN: 5/13/22). This region is particularly prone to faults and lies more than 1,000km from the InSight landing station.
According to Anna Mittelholz, a Harvard University planetary scientist, most of the Marsquakes associated with Cerberus Fossae have been quite familiar scientifically. Their seismic waves, which are low frequency, “are ones that look much more like what we see for an earthquake,” she says.
Mittelholz and her coworkers have now analysed a large number of Marsquakes. This includes more than 1000 high-frequency temblors. They are very different from their earthly counterparts. The researchers combined the weak signals to better understand the source of high-frequency earthquakes. The researchers found a peak in seismic energy emanating from Cerberus Folsae within the stack of seismic wave. That was an impressive undertaking, says Hrvoje Tkalčić, a geophysicist at the Australian National University in Canberra who was not involved with the research. “No study before this one attempted to locate the high-frequency quakes.”
Surprise! Different types of Marsquakes all cluster in the same region. Previous research has suggested that Marsquakes might be due to Mars’ surface cooling and shrinking over time. This is what causes the Marsquakes. This happens on the moonMittelholz states that this would result in temblors equally distributed over the planet.SN: 5/13/19). “The expectation was that Marsquakes would originate from all over the place.”
And by comparing the seismic waves that InSight measured with the seismic waves produced in different regions on our own planet, the researchers further showed that the low-frequency Marsquakes are probably produced by magma moving several tens of kilometers below Mars’ surface. “Our results are much more consistent with data from volcanic regions on Earth,” Mittelholz says.
The researchers concluded that Mars is not a dead planet in geology, as some had suggested. This finding rewrites our understanding of Mars, Mittelholz says, and there’s still so much more to learn about our celestial neighbor. “We’re only scratching the surface.”
