The Mississippian in Utah
359 - 318 Ma
The Mississippian Period is the lower division of the Carboniferous
Period and is named for coal-bearing sediments of this age found in the
Mississippi River valley. During the
Mississippian, there were two supercontinents called Laurasia and Gondwana with
the one big ocean known as the Tethys. The supercontinent Laurasia supported a
variety of lifeforms. Lepidodendron, a massive
tree named its scale like bark, thrived in the swampy lands of what would
become North America and Europe.
During the Mississippian, Utah was submerged beneath the waters of a shallow sea which deposited thick sequences of marine limestone. By Late Mississippian times, the ocean had receded to cover only the western portion of the state. Multiple marine transgressions and regressions left marine sediments within stream channels carved into those parts of eastern Utah that were often above sea level. As a consequence of the varying depositional environments, Mississippian fossils in the state include both marine organisms such as trilobites and mollusks as well as terrestrial plants such as Lepidodendron and ferns. To the west of Utah, the Antler Orogeny was producing highlands in what is now Nevada.
Manning Canyon Shale
During the Mississippian, Utah was submerged beneath the waters of a shallow sea which deposited thick sequences of marine limestone. By Late Mississippian times, the ocean had receded to cover only the western portion of the state. Multiple marine transgressions and regressions left marine sediments within stream channels carved into those parts of eastern Utah that were often above sea level. As a consequence of the varying depositional environments, Mississippian fossils in the state include both marine organisms such as trilobites and mollusks as well as terrestrial plants such as Lepidodendron and ferns. To the west of Utah, the Antler Orogeny was producing highlands in what is now Nevada.
Manning Canyon Shale
