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This is a list of Global Boundary Stratotype Sections and Points. Since 1977, Global Boundary Stratotype Sections and Points (abbreviated GSSPs) are internationally agreed upon reference points on stratigraphic sections of rock which define the lower boundaries of stages on the geologic time scale .
Because defining a GSSP depends on finding well-preserved geologic sections and identifying key events, this task becomes more difficult as one goes farther back in time. Before 630 million years ago, boundaries on the geologic timescale are defined simply by reference to fixed dates, known as "Global Standard Stratigraphic Ages" (GSSAs).
The Global Boundary Stratotype Section and Point (GSSP): overview; Chart of The Global Boundary Stratotype Sections and Points (GSSP): chart; Geotime chart displaying geologic time periods compared to the fossil record – Deals with chronology and classifications for laymen (not GSSPs)
A lower boundary is defined by locating a GSSP (informally known as 'golden spike') in the stratigraphic section of a stage, the chronostratigraphic taxonomic equivalent of an epoch. Alternatively, if a 'golden spike' cannot be located, a GSSA can be agreed upon, although this methodology is usually implemented for Precambrian boundaries. [19]
For younger stages, a Global Boundary Stratotype Section and Point (GSSP), a physical outcrop clearly demonstrates the boundary. For older stages, a Global Standard Stratigraphic Age (GSSA) is an absolute date. The benchmarks will give a much greater certainty that results can be compared with confidence in the date determinations, and such ...
The Brunhes–Matuyama reversal is a marker for the Global Boundary Stratotype Section and Point (GSSP) defining the base of the Chibanian Stage and Middle Pleistocene Subseries at the Chiba section, Japan, which was officially ratified in 2020 by the International Union of Geological Sciences.
A Global Boundary Stratotype Section and Point (GSSP), ratified by the IUGS in 2016, defines the base of the Albian as the first occurrence of the planktonic foraminiferan Microhedbergella renilaevis at the Col de Pré-Guittard section, Arnayon, Drôme, France.
For global stratigraphic correlation, the ICS ratify rock units based on a Global Boundary Stratotype Section and Point (GSSP) from a single formation (a stratotype) identifying the lower boundary of the unit. Currently the boundaries of the Cambrian System, three series and six stages are defined by global stratotype sections and points. [1]