Thermal Inertia
With GeoVirgil, you can analyze the thermal inertia of Martian rocks. Above is a picture showing thermal inertia in false colors and edge detected elevation data shown in yellow. You can see the the thermal inertial of rocks in the canyons is different than elsewhere in the scene.
Thermal inertia is a measurement of how much heat rocks hold. The dominate factor in thermal inertia is the size of pieces of rock. Where there is low thermal inertia (that is, where terrain heats and cools quickly) the surface tends to be made of fine grained dust or tiny rocks. Where there is high thermal inertia (that is, where the terrain temperature is more stable) you are more likely to find a surface made of very large pieces of rock.
GeoVirgil reads in the thermal inertia data set from MGS TES, product id GLOBAL_TI_60N_50S_8PPD.