Hi, BR.
I've been where you are right now. :)
Over the weekend, curiosity made me want to look further. I found these papers and I have a gut feeling that they are all related. The common culprit may be the Margaritifer Basin (connected to the Tharsis Trough)... don't call it a sea, don't call it a lake, but there was definite ponding going on there.
I started my search here:
Ancient Geodynamics and Global-Scale Hydrology on Mars.
http://www.nasm.si.edu/research/ceps/research/grant/grant_marg2.pdf
... last, but not least:
The History of Water Discharge in the Margaritifer Sinus region of Mars.
http://www.nasm.si.edu/research/ceps/research/grant/grant_marg.pdf
Then there's the suspected hydrothermal activity that occured in Meridiani Planum.
A meeting with the ponding and the hydrothermal activity must have taken place at the same time. It may have occured several times and possibly later on with underground ice/s. The Margaritifer Basin seems to have been a supplier of water.
Space/Science » in reply to re: So if I'm seeing things correctly (no guarantees)
re: So if I'm seeing things correctly (no guarantees)