A supercontinent that existed during the Neoproterozoic era (1000–542 Ma ago). Early in the Neoproterozoic the supercontinent Rodinia began to break apart and sections of cratons reassembled to form Pannotia, at the same time opening a sea that would eventually become the Pacific Ocean. Pannotia occupied much of the southern hemisphere, with a narrow arm of the sea separating a section that included East Gondwana and another section that included Laurasia. The supercontinent began to break up about 250 Ma later.