PILLOW LAVA ON TITAN - EXPECTATIONS AND CONSTRAINTS ON CRYOVOLCANIC PROCESSES

Titan offers a fascinating environment in which to consider cryovolcan ic processes: the Cassini/Huygens mission offers prospects for reveali ng cryovolcanic landforms, which may differ substantially from those o n the other icy satellites owing to the effect of Titan's dense atmosp here. Various aspects of possible cryovolcanism on Titan are investiga ted in an attempt to predict what might be discovered. The thermal and stress environment on Titan is considered, and likely eruption rates and styles investigated: it is found that volcanic landforms are likel y to be small, and ''ash'' cones are unlikely under present atmospheri c conditions on Titan. Cooling rates for likely cryomagmas are investi gated, and the possibility of rapidly-quenced pillow lavas is pointed out. Heat flow considerations limit the present resurfacing rate to <2 x 10(-3) m yr(-1): if atmospheric methane is buffered against photoly sis by volcanic resupply, then the resurfacing rate is >1.5 x 10(-5) m yr(-1). Copyright (C) 1996 Elsevier Science Ltd