Upper Ordovician graptolites from the top Lower Hartfell Shale Formation (D. clinganiandP. lineariszones) near Moffat, southern Scotland

Publisher Website
Google Scholar
Abstract
The top 9 m of Lower Hartfell Shale has been collected in 10 cm samples through a continuous sequence on the North Cliff at Dob's Linn. The boundary between theDicranograptus clinganiandPleurograptus lineariszones is denned for the first time in a measured section, 5.0 m below the top of the Lower Hartfell Shale, with the excavation of the North Cliff proposed as stratotype. The lateD. clinganiZone is characterised byDicranograptus ramosus?, Dicellograptus moffatensis, D. flexuosus[=D. forchhammeri], Climacograptus dorotheus, Glyptograptus daviesisp. nov.,Diplograptus? pilatussp. nov.,Neurograptus margaritatusandCorynoides calicularis. TheP. linearisZone is characterised byPleurograptus linearis linearis, Amphigraptus divergens divergens, Leptograptus capillaris, Dicellograptus elegans elegans, D. pumilis, D. carruthersiandClimacograptus tubuliferus. A range chart is provided and an attempt is made at a revised correlation of the Scottish succession with coeval zonal sequences in North America and Australia. Twenty-one taxa are described including the two new species noted above.