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The Status column has a "golden spike" for every GSSP which has been formally agreed by the ICS. Those without have only candidate sections which have not yet been formally ratified. The clock stands for times that are currently defined only by an age. The "Defining markers" column lists the evidence in the rock used to define the boundary.
A geologic section has to fulfill a set of criteria to be adapted as a GSSP by the ICS. The following list summarizes the criteria: [2] [3] A GSSP has to define the lower boundary of a geologic stage. The lower boundary has to be defined using a primary marker (usually first appearance datum of a fossil species).
In the stratigraphy sub-discipline of geology, a Global Standard Stratigraphic Age, abbreviated GSSA, is a chronological reference point and criterion in the geologic record used to define the boundaries (an internationally sanctioned benchmark point) between different geological periods, epochs or ages on the overall geologic time scale in a chronostratigraphically useful rock layer.
The Fortunian age marks the beginning of the Phanerozoic Eon, the Paleozoic Era, and the Cambrian Period It is the first of the two stages of the Terreneuvian series.Its base is defined as the first appearance of the trace fossil Treptichnus pedum 538.8 million years ago.
The Anthropocene Working Group (AWG) is an interdisciplinary research group dedicated to the study of the Anthropocene as a geological time unit. It was established in 2009 as part of the Subcommission on Quaternary Stratigraphy (SQS), a constituent body of the International Commission on Stratigraphy (ICS).
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You are free: to share – to copy, distribute and transmit the work; to remix – to adapt the work; Under the following conditions: attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made.
Status; Columns / Column width: 1 colwidth: Two modes supported. First mode (deprecated): integer number of fixed columns into which the reference list is to be rendered. Second mode: typographic unit of measurement such as 'em', specifying the width for the reference list columns, e.g. '33em'; spaced '33 em' will not be recognized. Default