Scientists have discovered solid sand in the martian canyon, which scientists speculate became solid 1 billion years ago. The surface features on this dune bear a striking resemblance to the recently formed sandy land, and studying this sandy ground can help us gain insight into sedimentary processes on Mars, while also revealing Earth's geological history.
Nasa has discovered one-billion-year-old dunes on Mars, and they are very similar to dunes on the surface
In a canyon on Mars, scientists have found a solid sand field blown by high winds. About 1 billion years ago, this sandy land became rocky.
This frozen plain of ancient sand dunes has stood the test of time and is more resistant to erosion than the fossils of Sandbo on Earth.
The study of the erosion resistance of these dunes can help us understand the sedimentation process of dunes on Mars, but also help to reveal the geological history of Mars.
Matthew Hoynecki, a planetary scientist at the Institute of Planetary Sciences, said: "It is rare for a terrestrial dune to be preserved to this extent due to continuous erosion and tectonic movement. Based on the relationship between dune sediments and other geological units and modern erosion rates, it can be inferred that these dunes are estimated to be about 1 billion years old. ”
On Mars, wind-blown dunes are a common feature, and in the widest part of mariner valley, Melas Canyon, the fixed dunes are sized and arranged in a way that is very similar to the recently formed dunes.
This suggests that the climate and atmosphere on Mars have barely changed for a long, long time. Astronomers say the direction, length, height, shape and slope of the ancient dunes of Melas Canyon are similar to the sand waves seen elsewhere on the planet.
Hoynatsky told Popular Science Magazine: "This shows that the main wind direction of the shape of the dunes has not changed substantially over time, and we have also seen dunes of very similar size and spacing in two periods." This suggests that no significant difference in atmospheric pressure may have occurred. ”
Using images from high-resolution imaging science experiments and Martian topographic data, the researchers obtained bed-like features of melas Canyon and dated it.
Although the canyon's topography is incomplete because some of the dunes have been eroded or buried, the researchers explain that the ancient dunes we were able to decipher "are not significantly different from the landforms we get from modern dunes." ”
The authors found that some of the dunes were buried beneath tens of meters of material that appeared to have come from a catastrophic event that had occurred on the volcano.
The authors predict that shortly after the catastrophic event, a volatile compound came into contact with the compacted dunes, hardening the dunes so that they froze in time as they crossed the Melas Canyon.
The same process can be seen on Earth, when groundwater invades partially buried sand dunes – formation of lithified sand layers, like those famous striped structures seen in Zion National Park. Unlike Earth, however, the litigmatized dunes on Mars have far fewer elements to deal with.
In the absence of water, vegetation or plate tectonics, trade winds are the main erosions on Mars. Over time, this helped to chisel the volcanic crust that once covered these dunes.
Sand dunes photographed by HiRISE cameras. (NASA/JPL - California Institute of Technology/University of Arizona)
The presence and preservation of these dunes indicates important differences in the evolution of the Earth and Martian landscapes.
Although paleoclithic dunes on Earth are rare and more eroded, Melas Canyon appears to have "extensive paleo-dune fields that pervade the bottom of the basin and are largely morphologically intact." ”
"Constantly reshaping the structure of the Earth's surface is not a factor with the current Mars, and we will have the opportunity to learn more about geology from the geological record of the Red Planet," Hoynecki said.
"These results tell us that for most of Mars' recent history, aeolian sand handling, sedimentation, and lithification have occurred, and illustrate that the geomorphological evolution of Mars is very different from the evolution of Earth's landform."
The study was published in the journal JGR Planet.
Related knowledge
Mars, the fourth closest planet to the Sun, is the second smallest planet in the Solar System after Mercury, and is one of the four Terrestrial planets in the Solar System. The West calls Mars Mars, the god of war in Roman mythology, so in English, Mars is the meaning of the Roman god of war, usually called "Red Planet"; in ancient Chinese, it is called Ying confusion because it is like a fire, and the position and brightness often change unpredictably.
BY: CARLY CASSELLA
FY: Small circle
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