QUOTE (dvandorn @ Oct 22 2005, 08:02 AM)
I think we need heat flow measurements from several thousands locations on Mars, and seismometers in several hundred locations, before we can even start to theorize about the current state of Mars' mantle and core...
-the other Doug
The only hints we have is what we can see on the surface:
-Tharsis dome
-Volcanoes
-fault zones around the Tharsis dome
-Vales Marineris
-two different origins for lavas
This gives some suggestion, for instance that it does not look like a Earth like convection scheme. But is not enough to give an overal shema of martian interior. What we need, I think, would be an extensive network of seismometres to have a map of inner Mars. And a coarse map is very likely to show only an homogenous mantle. The interesting features are likely to be small (lava chambers and chimneys) and scarcely "visible" (very weak differences in propagation speed, like hot spots on Earth).
Many seismometres would be expensive; but eventually we could do with less seismometres and many impacts which are cheaper to provide.