“…Subsequently, data from the Viking Orbiters (Carr et al, 1977b) allowed mapping and characterization of the extent, timing, and styles of volcanism on Mars (Figure 1; Greeley andSpudis, 1978, 1981;Mouginis-Mark et al, 1992;Greeley et al, 2000). High resolution images (Malin et al, 1998) (Figure 1), information on surface compositions (McSween et al, 1998), and topographic data (Smith et al, 1998(Smith et al, , 1999a from the Mars Global Surveyor (MGS) permit comparison of Martian volcanism with theoretical analysis of the ascent and eruption of magma on Mars (e.g., Wilson and Head, 1994).…”