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Which geologic stages make up the Middle Jurassic Epoch?
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Jurassic Period
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the late Jurassic Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The Middle Jurassic Epoch, which occurred approximately 174.1 million to 163.5 million years ago, is subdivided into four geologic stages. These stages are:1
These intervals are often established using index fossils such as ammonites, though global correlation can be challenging due to the limited geographic distribution of many species.1