{"title":"加拿大东部quemassube半岛东南部西点组(志留系)基底海红色化石","authors":"S. Donovan, D. Keighley","doi":"10.4138/ATLGEOL.2016.010","DOIUrl":null,"url":null,"abstract":"Silurian strata of Atlantic Canada and southern Quebec locally preserve common fossil crinoids, albeit mostly as disarticulated remains. New crinoids from the Chaleurs Group, West Point Formation (Ludlow to Pridoli?; Upper Silurian) of the Gaspe Peninsula include Iocrinus ? maennili (Yeltysheva) (otherwise known from the Katian of Estonia), Bystrowicrinus (col.) depressus sp. nov. and Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus Donovan. On the basis of both its gross morphology and stratigraphic position, Iocrinus ? maennili is unlikely to be an iocrinid disparid, a family that became extinct at the end of the Ordovician. The trivial name has hitherto been erroneously spelled as mannili , mannili and mjannili . Most specimens of the common Bystrowicrinus (col.) depressus appear cyclocyclic because the pentastellate lumen occurs in a deeply sunken claustrum that is commonly occluded by sediment; clean specimens are highly distinctive. Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus is similar to a species known from the Katian of North Wales. Taken together, this assemblage is more reminiscent of Katian strata (Upper Ordovician). Ḁis is problematic given the current mapping of the outcrop as West Point Formation (Upper Silurian), suggesting further stratigraphic studies in the area are required.","PeriodicalId":49235,"journal":{"name":"Atlantic Geology","volume":"52 1","pages":"211-222"},"PeriodicalIF":1.2000,"publicationDate":"2016-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Fossil crinoids from the basal West Point Formation (Silurian), southeast Gaspé Peninsula, Québec, eastern Canada\",\"authors\":\"S. Donovan, D. Keighley\",\"doi\":\"10.4138/ATLGEOL.2016.010\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Silurian strata of Atlantic Canada and southern Quebec locally preserve common fossil crinoids, albeit mostly as disarticulated remains. New crinoids from the Chaleurs Group, West Point Formation (Ludlow to Pridoli?; Upper Silurian) of the Gaspe Peninsula include Iocrinus ? maennili (Yeltysheva) (otherwise known from the Katian of Estonia), Bystrowicrinus (col.) depressus sp. nov. and Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus Donovan. On the basis of both its gross morphology and stratigraphic position, Iocrinus ? maennili is unlikely to be an iocrinid disparid, a family that became extinct at the end of the Ordovician. The trivial name has hitherto been erroneously spelled as mannili , mannili and mjannili . Most specimens of the common Bystrowicrinus (col.) depressus appear cyclocyclic because the pentastellate lumen occurs in a deeply sunken claustrum that is commonly occluded by sediment; clean specimens are highly distinctive. Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus is similar to a species known from the Katian of North Wales. Taken together, this assemblage is more reminiscent of Katian strata (Upper Ordovician). Ḁis is problematic given the current mapping of the outcrop as West Point Formation (Upper Silurian), suggesting further stratigraphic studies in the area are required.\",\"PeriodicalId\":49235,\"journal\":{\"name\":\"Atlantic Geology\",\"volume\":\"52 1\",\"pages\":\"211-222\"},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2016-11-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Atlantic Geology\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.4138/ATLGEOL.2016.010\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"GEOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Atlantic Geology","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.4138/ATLGEOL.2016.010","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOLOGY","Score":null,"Total":0}
Fossil crinoids from the basal West Point Formation (Silurian), southeast Gaspé Peninsula, Québec, eastern Canada
Silurian strata of Atlantic Canada and southern Quebec locally preserve common fossil crinoids, albeit mostly as disarticulated remains. New crinoids from the Chaleurs Group, West Point Formation (Ludlow to Pridoli?; Upper Silurian) of the Gaspe Peninsula include Iocrinus ? maennili (Yeltysheva) (otherwise known from the Katian of Estonia), Bystrowicrinus (col.) depressus sp. nov. and Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus Donovan. On the basis of both its gross morphology and stratigraphic position, Iocrinus ? maennili is unlikely to be an iocrinid disparid, a family that became extinct at the end of the Ordovician. The trivial name has hitherto been erroneously spelled as mannili , mannili and mjannili . Most specimens of the common Bystrowicrinus (col.) depressus appear cyclocyclic because the pentastellate lumen occurs in a deeply sunken claustrum that is commonly occluded by sediment; clean specimens are highly distinctive. Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus is similar to a species known from the Katian of North Wales. Taken together, this assemblage is more reminiscent of Katian strata (Upper Ordovician). Ḁis is problematic given the current mapping of the outcrop as West Point Formation (Upper Silurian), suggesting further stratigraphic studies in the area are required.
期刊介绍:
Atlantic Geology (originally Maritime Sediments, subsequently Maritime Sediments and Atlantic Geology) covers all aspects of the geology of the North Atlantic region. It publishes papers, notes, and discussions on original research and review papers, where appropriate to the regional geology.