Cambrian microfossils from glacial erratics of King George Island, Antarctica
Cambrian microfossils from glacial erratics of King George Island, Antarctica
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发表时间：
2004
影响因子：
1.8
通讯作者：
R. Wrona
中科院分区：
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作者：
R. Wrona
南极乔治王岛早中新世冰海梅尔维尔角组的灰岩异常产出了早、中寒武世的小骨骼化石，并伴有钙化的蓝藻、古杯、针状海绵、三叶虫和棘皮动物。SSF组合包括chelloriids，halkieriids，tommotiids，lapericellids，palaeoscolecids，hyolithelminths，lingulate腕足动物，helcionelloid软体动物，hyoliths和bradoriids的分离骨片。所有24个物种都是南极洲和澳大利亚的常见物种。大多数是首次在南极洲记录，包括Shetlandia multiplicata gen. et sp. nov.和两个新物种Byronia？bifida和Hadimopanella vulgata。巨石的岩性和化石成分与阿根廷山脉和横贯南极山脉沙克尔顿石灰岩的原生组合几乎相同。威德尔海周围的寒武纪露头是不稳定的一个可能的来源。该动物群与弗林德斯山脉最上层的Botomian Wilkawillina石灰岩和约克半岛的Parara石灰岩、弗林德斯山脉的Toyonian Wirrealpa和Aroona Creek石灰岩以及约克半岛的Ramsay石灰岩非常相似，这些石灰岩都位于南澳的Arrowie和Stansbury盆地。南极洲和澳大利亚的这些非常相似的动物群和相序列强烈支持它们在整个早寒武世在更大的冈瓦纳超大陆的同一边缘上的共同生物和沉积演化。
Limestone erratics in the Early Miocene glacio-marine Cape Melville Formation of King George Island, Antarctica, have yielded Early and Middle Cambrian small skeletal fossils (SSF) accompanied by calcified cyanobacteria, archaeocyath and spiculate sponges, trilobites and echinoderms. The SSF assemblage comprises disarticulated sclerites of chancelloriids, halkieriids, tommotiids, lapworthellids, palaeoscolecids, hyolithelminths, lingulate brachiopods, helcionelloid molluscs, hyoliths, and bradoriids. All 24 described species are common to Antarctica and Australia. Most are recorded here from Antarctica for the first time, including Shetlandia multiplicata gen. et sp. nov. and two new species Byronia? bifida and Hadimopanella staurata. The lithological and fossil contents of the boulders are almost identical with autochthonous assemblages from the Shackleton Limestone in the Argentina Range and Transantarctic Mountains. Cambrian outcrops around the Weddell Sea are a plausible source of the erratics. The fauna is closely similar to that from the uppermost Botomian Wilkawillina Limestone in the Flinders Ranges and Parara Limestone on Yorke Peninsula, and Toyonian Wirrealpa and Aroona Creek Limestones in the Flinders Ranges, as well as the Ramsay Limestone on Yorke Peninsula, all in the Arrowie and Stansbury Basins of South Australia. These very similar faunal and facies successions for Antarctica and Australia strongly support their common biotic and sedimentary evolution on the same margin of a greater Gondwana supercontinent throughout the Early Cambrian.