Global Boundary Stratotype Section and Point

The Global Boundary Stratotype Section and Point (GSSP) is a specific type of geological marker used to define the boundaries between different geological time intervals, known as stages or epochs, in the geological time scale. The GSSP is a formally recognized reference point that is designated by the International Union of Geological Sciences (IUGS). The concept of GSSP arose from the need for a global standard to facilitate communication and correlation of geological time across different regions and disciplines.