The Ordovician graptolite sequence of Australasia

Graptolite biostratigraphy of the Shihtien Formation (Darriwilian) in West Yunnan, China

“…The occurrence of Pterograptus sp., although with only one specimen in BPSD-1, further supports this correlation. The D. murchisoni Biozone is also well correlated with the same biozone in Britain (Fortey et al 1995(Fortey et al , 2000, the Yangtze region of South China (Zhang et al 2007), the lower part of the Archiclimacograptus riddellensis Biozone in Australia (VandenBerg & Cooper 1992), and the Pterograptus elegans Biozone in Argentina (Brussa et al 2003a, b).…”

“…The lower part of the Shihtien Formation, composed of sandstone and calcareous sandstone, contains no graptolites. However, Undulograptus austrodentatus was found from the top part of the underlying Laojiangshan Formation in some other sections near Shidian (Yunnan Geological Survey 1980, p. 33), and hence the lower part of the Shihtien Formation probably corresponds to the transition interval between the U. austrodentatus and D. artus biozones, equivalent to the Undulograptus intersitus Biozone of the Yangtze Region (South China, Zhang & Chen 2003, Zhang et al 2007) and Australasia (VandenBerg & Cooper 1992), and the Undulograptus dentatus Biozone of North America (Maletz 2005). The D. artus Biozone in west Yunnan is comparable with that recognized in Changning, Sichuan, South China (Zhang et al 2007), and in Britain (Fortey et al 1995(Fortey et al , 2000.…”

Darriwilian graptolites of the Shihtien Formation (Ordovician) in west Yunnan, China

“…The D. murchisoni Biozone is also recognized in Britain (Cooper et al 1995, Fortey et al 2000, and correlates with the lower part of the Archiclimacograptus riddellensis Biozone of Australia (VandenBerg & Cooper 1992), and the Pterograptus elegans Biozone of Argentina (Brussa et al 2003a, b).…”

“…These graptolites occur mainly in the upper part of the Shihtien Formation, whereas the lower part comprising sandstones and calcareous sandstones is barren of graptolites. However, Undulograptus austrodentatus (Harris & Keble, 1932) was found in the top part of the underlying Laojianshan Formation in some sections near Shidian (Yunnan Geological Survey 1980), hence the lower part of the Shihtien Formation possibly corresponds to the transition interval between the U. austrodentatus Biozone and the D. artus Biozone, and is probably equivalent to the Undulograptus intersitus Biozone in the Yangtze Region of ALCHERINGA ORDOVICIAN GRAPTOLITES FROM CHINASouth China (Zhang & Chen 2003, Zhang et al 2007) and Australasia (VandenBerg & Cooper 1992), and the Undulograptus dentatus Biozone in North America (Maletz 2005). Equivalent assemblages of the D. artus Biozone are recognized in Changning, Sichuan, South China (Zhang et al 2007) and in the British D. artus Biozone (Fortey et al 1995(Fortey et al , 2000.…”

Late Castlemainian (Ca 4, Arenig) graptolites from the Ballantrae Complex, SW Scotland

“…Yutagraptus: v-deflexus was indicated to be restricted to the Yapeenian and early Darriwilian by Vandenberg & Cooper (1992). However, the species is common in the Isograptus victoriae maximo diver gens Biozone of western Newfoundland (Williams & Stevens 1988: identified as Xiphograptus deelinatus), extending its range downwards.…”