You might want to check out this apparent active vent in Elysium Fossae...

Known colloquially as "Dan's Smoker" ;-)
From:

http://ida.wr.usgs.gov/html/ab1020/ab102003.html

I've been scouring images of Elysium and nearby areas for any other sign of current activity, so far without unqualified success. There have been some hints here and there, but nothing as apparently clear cut as this one. Problem is, the image here is, shall we say, less than perfect.

Only recently started sorting through the THEMIS images of the region. Haven't found any unambiguous signs of geyser-heat... (not that I'd necessarily recognize it if I did!) but one thing is real obvious: many of the pits and troughs are brilliantly "hot" in nighttime infrared, as are some in daytime infrared.

I don't make too much of this though. Many of the troughs (which appear to be collapse formations) have very dark material on their floors, material which seems to originate from a thin layer on the trough walls. I assume it absorbs heat in the daytime and radiates it at night. However, in some cases, the nighttime infrared brilliance of these troughs is truly spectacular.

I wonder if the relative heat of this black (or at least dark) material is affecting the erosion of the troughs, and I wonder what effect this heat has on atmospheric circulation, cloud generation and so forth.

Cheers, BRFelix