Tip of the hat to Coach for steering me to this one.
‘Bedrock holds one quintillion (1018) Joules of impact heat, centered on the new, lowest point on Mars. Here 1.3 kPa of atmospheric pressure, the depressions, and crater heat make possible a lake and other reservoirs for settlement use. Water surface temperature is set via circulation and heat exchange below 11 °C to prevent boil-off.’
That’s what I was wondering about, just how much heat and how long would it stay hot? Looks like a lot, and for a long time. Time for me to purchase some Mars liquid water rights.