Abstract
It is known that Martian volcanoes have been active until recently. The morphological studies on lava flows have been conducted to estimate magmatic types and eruption styles. Because of limited resolution of the surface image and lack of reliable data of surface gradient, the obtained results are not so conclusive. Recent data by MGS have greatly improved the quality of these data. Based on these we conduct comparative study of morphology of lava flows in Tharsis and Elysium regions. The studied lava flows are located in the northwestern skirt of Ascreus Mons and the southeastern skirt of Elysium Mons. Both are selected because of great length(>several hundreds of km). The flows in Ascreus Mons have many similarities to the terrestrial continental flood basalt, whereas that in Elysium Mons indicates higher viscosity.
