Impacts and Clathrate flows on Mars
This is a nice image, as very unusually, the impact crater is isolated, and this allows the individual features to be clearly seen:
http://themis.la.asu.edu/zoom-20020705a.html
While on the surface of Mars, as on Earth, generalizations are difficult, as conditions vary from area to area, note that on the Earth, impacts NEVER lead to outflows. That's because the Earth's lithosphere is very different from that of Mars.
Note also the small channel leading off to the bottom right of the crater, which is indicative of the total amount of water held in the top layer of Mars' "soil".
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