On the topography of extrasolar earthlike planets

We consider a class of planets which have experienced early, nearly complete differentiation and outgassing, whose mantles are fully convective, and whose crusts are isostatically compensated. The evolutionary model of Hargraves [Science193, 363 (1976)] suggests that in the absence of a runaway greenhouse, such planets may usually possess continent/ocean topographies similar to that of Earth. But if the planet is significantly larger than Earth, and its star of spectral type earlier than G, it may ordinarily be completely water-covered.