Reply

Treiman (this issue) argues that the melting temperature of carbonatite used by Gregg and Greeley (1993) is too low, and that values presented for other thermophysical properties for carbonatite lava are more appropriate for carbonatite rock. With the exception of the mechanical solidification temperature, values presented by Gregg and Greeley (1993) were taken directly, or calculated, from values presented within the works by Dawson et al. (1990) and Keller and Krafft (1990). Because a mechanical solidification temperature for carbonatite lavas was not presented in those works, we estimated one based on extrusion temperature, Venusian surface pressure, and the temperatures measured in cooling carbonatite lava lakes. We have reexamined values shown for properties of carbonatite lavas used by Gregg and Greeley (1993), and concur that Treiman's arguments (Treiman, this issue) are valid. Here, we present results of analyses described in Gregg and Greeley 1993, using values for the properties of carbonatite lavas obtained from Treiman and Schedl (1983) and Norton and Pinkerton (1990).