Opening of the North Atlantic Ocean Plateau (off Norway), Faroe-Shetland Basin, Hebrides, Outer Moray Firth and Denmark. The supercontinent known as Pangea existed during the late Paleozoic and early Mesozoic eras and began to rift around 200 million years ago. Pangea had three major phases of breakup. The first major phase began in the Early-Middle Jurassic, taking place between North America and Africa. The second major phase of breakup began in the Early Cretaceous. The South Atlantic Ocean opened around 140 million years ago as Africa separated from South America, and about the same time, India separated from Antarctica and Australia, forming the central Indian Ocean.
Geological period example the 'Jurassic System' of rocks was formed during the 'Jurassic Period' (between 201 and 145 million years ago). The following table includes all currently recognized periods. The table omits the time before 2500 million years ago, which is not divided into periods. See Geologic time scale#Proposed Precambrian timeline for another set of periods 4600–541 MYA. In a steady effort ongoing since 1974, the International Commission on Stratigraphy has been working to correlate the world's local stratigraphic record into one uniform planet-wide benchmarked system. American geologists have long considered the Mississippian and Pennsylvanian to be periods in their own right