Volcanic flow development at Alba Patera, Mars

On the Alba Patera volcanic shield of Mars, a Hesperian flood-lava phase was followed by the extrusion of sheet lavas and tube-fed lavas emerging in many cases from the flanking fissures of rising domes. These events were followed by the eruption of additional sheet and tube-fed lavas from linear vents which formed complex flow fields. Later, Amazonian volcanism at Alba involved long, narrow flows from two complex summit calderas; the thermal energy outflow for some individual flows would have been substantially greater than the annual heat loss of the earth through volcanism, implying that the process of patera-building represented substantial Martian geological heat-loss during the planet's early volcanic-centralization stages. 40 refs