Mississippian (geology)

Source: Wikipedia, the free encyclopedia.
Mississippian
358.9 ± 0.4 – 323.2 ± 0.4 Ma
Subperiod
Time span formalityFormal
Lower boundary definitionFAD of the Conodont Siphonodella sulcata (discovered to have biostratigraphic issues as of 2006)[2]
Lower boundary GSSPLa Serre, Montagne Noire, France
43°33′20″N 3°21′26″E / 43.5555°N 3.3573°E / 43.5555; 3.3573
Lower GSSP ratified1990[3]
Upper boundary definitionFAD of the Conodont Declinognathodus nodiliferus
Upper boundary GSSPArrow Canyon, Nevada, United States
36°44′00″N 114°46′40″W / 36.7333°N 114.7778°W / 36.7333; -114.7778
Upper GSSP ratified1996[4]

The Mississippian (

Mississippi Valley
.

The Mississippian was a period of marine transgression in the Northern Hemisphere: the sea level was so high that only the Fennoscandian Shield and the Laurentian Shield were dry land. The cratons were surrounded by extensive delta systems and lagoons, and carbonate sedimentation on the surrounding continental platforms, covered by shallow seas.[6]

In North America, where the interval consists primarily of marine limestones, it is treated as a geologic period between the Devonian and the Pennsylvanian. During the Mississippian an important phase of orogeny occurred in the Appalachian Mountains. The USGS geologic time scale shows its relation to other periods.[7]

In

Upper Carboniferous
and Lower Carboniferous instead.

Subdivisions

In the international geologic timescale, the Mississippian is subdivided into three stages:

The lower two come from European stratigraphy, the top from Russian stratigraphy. Besides Europe and Russia, there are many local subdivisions that are used as alternatives for the international timescale. In the North American system, the Mississippian is subdivided into four stages:

  • Chesterian (top of the Visean plus the Serpukhovian)
  • Meramecian
    (middle Visean)
  • Osagean (top of the Tournaisian and bottom of the Visean)
  • Kinderhookian
    (the lower two-thirds of the Tournaisian)

References

  1. ^ "International Chronostratigraphic Chart" (PDF). International Commission on Stratigraphy. September 2023. Retrieved November 10, 2024.
  2. . Retrieved 7 December 2020.
  3. ^ Paproth, Eva; Feist, Raimund; Flajs, Gerd (December 1991). "Decision on the Devonian-Carboniferous boundary stratotype" (PDF). Episodes. 14: 331–336.
  4. ^ Lane, H.; Brenckle, Paul; Baesemann, J.; Richards, Barry (December 1999). "The IUGS boundary in the middle of the Carboniferous: Arrow Canyon, Nevada, USA" (PDF). Episodes. 22: 272–283. Retrieved 8 December 2020.
  5. ^ "Mississippian". Dictionary.com Unabridged (Online). n.d.
  6. ^ Cesare Emiliani, Planet Earth: Cosmology, Geology, and the Evolution of Life and Environment 1992 496.
  7. ^ USGS Timescale