Bulletin of geosciences | |
At what stratigraphical level is the mid Ludfordian (Ludlow, Silurian) positive carbon isotope excursion in the type Ludlow area, Shropshire, England? | |
Frýda J1  Loydell DK1  | |
关键词: Silurian; Ludlow; carbon isotopes; conodonts; chitinozoans; thelodonts; stratigraphy; | |
DOI : | |
来源: Czech Geological Survey | |
【 摘 要 】
ThebalanceofevidencesuggeststhatthemidLudfordianpositivecarbonisotopeexcursion(CIE)commencesintheLudlowarea,EnglandintheuppermostUpperWhitcliffeFormation,withtheexcursioncontinuingintoatleastthePlatyschismaShaleMemberoftheoverlyingDowntonCastleSandstoneFormation.TheLudlowBoneBedMember,atthebaseoftheDowntonCastleSandstoneFormationhaspreviouslybeenconsideredtobeofPAâ„¢AÂdolAÂage.Conodontandthelodontevidence,however,areconsistentwiththemidLudfordianageproposedhere.Newdelta;13CorgdataarepresentedfromWeirQuarry,WofLudlow,showingapronouncedpositiveexcursioncommencingintheuppermostUpperWhitcliffeFormation,instratawithapalynologicallyverystrongmarineinfluence.Elsewhereintheworld,themidLudfordianpositiveCIEisassociatedwithmajorfacieschangesindicatedshallowing;thelithofaciesevidencefromtheLudlowareaisconsistentwiththis.ThereappearsnottobeamajorstratigraphicalbreakatthebaseoftheLudlowBoneBedMember.
【 授权许可】
Unknown
【 预 览 】
Files | Size | Format | View |
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RO201912090783078ZK.pdf | 349KB | download |