More Than Just Basalt
Mineral maps from the Thermal Emission Spectrometer on NASA's Mars Global Surveyor showed the variety of surface rocks on Mars. This data let scientists interpret multispectral images taken with Mars Odyssey's Thermal Emission Imaging System, such as this infrared image of Nili Patera caldera on Syrtis Major. The dacite flow (magenta) and the volcanic cone associated with it have a composition distinct from the basaltic lavas that comprise most of the caldera floor (blue). Small outliers of dacitic material lie east of the cone. Image width is 16 km (10 miles).
Last Update: 8 Feb 2013 (AMB)