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Pangaea or Pangea (/ p æ n ˈ dʒ iː ə / pan-JEE-ə) [1] was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. [2] It assembled from the earlier continental units of Gondwana , Euramerica and Siberia during the Carboniferous approximately 335 million years ago, and began to break apart about 200 million years ...
Pangaea's supercontinent cycle is a good example of the efficiency of using the presence or lack of these entities to record the development, tenure, and break-up of supercontinents. There is a sharp decrease in passive margins between 500 and 350 Ma during the timing of Pangaea's assembly.
The subdivisions of the Mesoproterozoic are arbitrary divisions based on time. They are not geostratigraphic or biostratigraphic units. The decision to base the Precambrian time scale on radiometric dating reflects the sparse nature of the fossil record, and Precambrian subdivisions of geologic time roughly reflect major tectonic cycles.
The Mesozoic Era [3] is the era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Periods.It is characterized by the dominance of gymnosperms such as cycads, ginkgoaceae and araucarian conifers, and of archosaurian reptiles such as the dinosaurs; a hot greenhouse climate; and the tectonic break-up of Pangaea.
Pangea began to break up about 220 million years ago, in the early Mesozoic (late Triassic period). As Pangea rifted apart a new passive tectonic margin was born, and the forces that created the Appalachian, Ouachita, and Marathon Mountains were stilled. Weathering and erosion prevailed, and the mountains began to wear away.
Fossil footprints are the most common kind of early dinosaur fossil in the eastern United States. [57] As the Triassic ended, Pangaea was breaking up into separate continents again. Rift valleys formed along the east coast as the North American, European and African plates diverged. [58] This process created rifts down the east coast to Florida ...
The vast supercontinent of Pangaea dominated the globe during the Triassic, but in the latest Triassic and Early Jurassic it began to gradually rift into two separate landmasses: Laurasia to the north and Gondwana to the south. The global climate during the Triassic was mostly hot and dry, [12] with deserts spanning much of Pangaea's interior ...
Geologic map of North America, color-coded by age. From most recent to oldest, age is indicated by yellow, green, blue, and red. The reds and pinks indicate rock from the Archean. Mantle convection, the process that drives plate tectonics, is a result of heat flow from the Earth's interior to the Earth's surface.