Martian Tsunamis May Be Related to Impact Craters

Scientists have located an impact crater linked to powerful tsunamis that cleared across part of ancient Mars.

According to the authors of the study, the over 90 mile wide Lomonosov crater, located in Mars' northern plains, was created by an asteroid that, when it struck the said ocean about three billion years ago, triggered tsunami waves reaching heights of almost 500 feet. In-depth information was outlined at the 48th Lunar and Planetary Science Conference. Detailed observations of the red planet's atmosphere and surface have led scientists to speculate that perhaps about 3.8 billion years ago, Mars had enough liquid water to form an ocean occupying nearly half of its northern hemisphere.

According to Dr. Clifford, it's tough to think of a different explanation to the lobate deposits that is not the massive ancient tsunamis, essentially due to their location (the dichotomy boundary between the northern and southern hemisphere).

By mapping the distribution of sediment and inputting it into a computer model, the research team believes the wave originated in the northern plains and flowed southward to the ancient ocean's shoreline. Dr Clifford, from the Lunar and Planetary Institute in Houston, explained the evidence.

"There's also a second set of landforms that we see along the coastline called thumbprint terrain...the reflection of the tsunami waves from the coast, and their interaction with a second set of tsunami waves, predicted by the numerical modeling, would have resulted in sediment deposition that's very similar to what we actually observe on Mars", he noted.

This terrain has previously been interpreted as having been caused by glaciers, mud flows and mud volcanoes.

The new research also explains the rather unusual topographical features known as thumbprint terrain, which have been found on the seaward extremes of some of the tsunami deposits.

Since then, scientists have realised that if one of the many asteroids that pocked the Martian surface happened to crash into that ocean, a tsunami was a likely possibility.

"It was a really large-scale, high speed tsunami", Dr. Costard explained, according to the Christian Science Monitor.

"There is ambiguity in all the various lines of evidence that have been cited regarding whether Mars is water-rich or water-poor". "At the very beginning, a crater of 70 kilometers (43.5 miles) in diameter was created by the impact".

Mars, despite its current rusted and parched appearance, was once a world where water flowed freely.

The waves rose to around 400 feet in height and produced shore-break waves with 150-feet-tall waves at an average.

The first of the two waves was 300m high, it would have reached the palaeo-shoreline within hours crushing on hills and plateaus.

This phenomenon is believed to be a cyclic one and repeats itself three to seven times over billions of years.

According to the lead author of the study, François Costard, the fact that the team had found those deposits that tsunamis often produce is key to the study and its allegations. "We mapped lobate deposits, which appear and are potential tsunami deposits associated with the existence of a former ocean".

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  • Carolyn Briggs