Q.E.D.: Clathrate Reactions on Mars
Since this seems to have escaped everyone's notice the first time around, I thought I would post it again:
In the following image, typical for the surface of Mars, note the long straight channels formed when CO2/H2O clathrates are released by the heat generated during the entry of an impactor meeting Mars at an angle low to the Mars's surface, that is to say "obliquely":
http://themis.la.asu.edu/mars-bin/mars_cgi_map.pl?CENT_LAT=-37.37097176&CENT_LON=170.1670353&RESCALE=64&TNAIL_LINK=20020611a
There is no other phenomenon which can explain these formations other than clathrate reactions.
Also, this is not simply a shallow surface phenomenon, as among the other straight channels on Mars there are several which are fairly deep.
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