HiRISE Science Team wrote:Cratered Cones in Tartarus Montes (ESP_033252_2070) (HiClip)
Many types of craters exist on Mars. Most are generated by impacts of asteroids and comets.
In this area though, we think these craters may be due to steam explosions. This happens on the Earth when hot lava runs over icy ground.
HiRISE Science Team wrote:Breached Rim of a Circular Depression (ESP_033243_2165) (HiClip)
This image shows an impact crater with a diameter of approximately 2 kilometers located in the Coloe Fossae region of Mars.
It is partially filled with a sediment flow that has breached the south rim and continues northwards for approximately 4 kilometers before abruptly terminating in a rounded lobe of blocky material.
HiRISE Science Team wrote:Hints of an Ancient Shoreline in Southern Isidis Planitia (ESP_033242_1845) (HiClip)
This area--known as the Deuteronilus contact of the Isidis Basin--has been interpreted as a possible ancient shoreline. There are also suggestions that this contact is of volcanic origin.
One direct benefit of a high resolution image is the ability to monitor the detailed morphology of the contact to help to determine whether this formation is the result of an ocean or of a volcanic filling of the Isidis Basin.
Lazlo Kestay wrote:Dust Covered Channels on Tharsis Tholus (ESP_033565_1945) (HiClip)
Tharsis Tholus is one of the smaller shield volcanoes on Mars' massive "Tharsis Rise." The main shield is covered by a very thick blanket (or "mantle") of loose material. This is likely to be the same dust that is found across all of Mars.
It accumulates on the tall volcanoes because the thin atmosphere at these elevations has a very hard time moving the dust after it is dropped out from the global dust storms. But another reason for the great thickness of the mantle here could be volcanic ash derived from the volcanos themselves.
The flanks of Tharsis Tholus are cut by large channels, similar to those visible on other Martian shield volcanos like Arsia Mons and Elysium Mons. Like the channels on those volcanos, these channels probably formed by a combination of erosion by flowing lava, and the collapse of the volcano under its own weight. However, because of the thick covering, we cannot say this definitively.
A striking feature at the northern end of this image is the fact that the dust cover is much thinner on the lava flows that surround the shield. This indicates (1) the surrounding lavas are much younger than the shield and (2) the mantle on the volcanos is old.
Credit: NASA/JPL/University of Arizona
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