Gorstian
{{short description|Sixth stage of the Silurian}}
{{Infobox geologic timespan
| name = Gorstian
| color = Gorstian
| time_start = 427.4
| time_start_uncertainty = 0.5
| time_end = 425.6
| time_end_uncertainty = 0.9
| image_map = Geology of Asia 425Ma.jpg
| caption_map = Paleogeography of the late Gorstian, 425 Ma
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| timeline = Silurian
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| name_formality = Formal
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| celestial_body = earth
| usage = Global (ICS)
| timescales_used = ICS Time Scale
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| chrono_unit = Age
| strat_unit = Stage
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| timespan_formality = Formal
| lower_boundary_def = FAD of the graptolite Saetograptus (Colonograptus) varians
| lower_gssp_location = Pitch Coppice, Ludlow, U.K.
| lower_gssp_coords = {{Coord|52.3592|N|2.7772|W|display=inline}}
| lower_gssp_accept_date = 1980
| upper_boundary_def = Imprecise. Near FAD of the graptolite Saetograptus leintwardinensis
| upper_def_candidates = None
| upper_gssp_candidates = None
| upper_gssp_location = Sunnyhill, Ludlow, England
| upper_gssp_coords = {{Coord|52.3592|N|2.7772|W|display=inline}}
| upper_gssp_accept_date = 1980
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In the geologic timescale, the Gorstian is an age of the Ludlow Epoch of the Silurian Period of the Paleozoic Era of the Phanerozoic Eon that is comprehended between 427.4 ± 0.5 Ma and 425.6 ± 0.9 Ma (million years ago), approximately. The Gorstian Age succeeds the Homerian Age and precedes the Ludfordian Age.{{cite book |isbn=9780521786737|title=A Geologic Time Scale 2004|last1=Gradstein|first1=Felix M.|last2=Ogg|first2=James G.|last3=Smith|first3=Alan G.|year=2004}} The age is named after Gorsty village southwest of Ludlow. The base of the age is marked by Saetograptus (Colonograptus) varians. The type section is located in a quarry in the Elton Formation at Pitch Coppice, Shropshire, United Kingdom.