Sentences with phrase «stable rocky crust»

Eventually, a stable rocky crust may have developed between Years 0.2 and 0.4 billion (see J. Bret Bennington's discussion of recycled zircons (crystals of zirconium silicate) from the rocks of western Australia in the Hadean Eon and the January 11, 2001 announcement of zircons found north of Perth that appear to be 4.4 billion years old), covered and surrounded by soupy water that was already rich with organic compounds from interstellar space.