The middle Cambrian cosmopolitan key species Lejopyge laevigata and its biozone: new data from Sweden
The middle Cambrian cosmopolitan key species Lejopyge laevigata and its biozone: new data from Sweden
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DOI：
10.1017/s0016756806002007
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发表时间：
2006-05
影响因子：
2.3
通讯作者：
N. Axheimer;M. Eriksson;P. Ahlberg;Anders Bengtsson
中科院分区：
文献类型：
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作者：
N. Axheimer;M. Eriksson;P. Ahlberg;Anders Bengtsson
中寒武系Lejopyge laevigata带在斯堪的纳维亚半岛出露程度较低。然而，这个区域以及随后的 Agnostus pisiformis 区域都在瑞典中南部西约特兰省古德姆的经典地点中得到了很好的暴露。这些序列由精细层压的明矾页岩和分散的臭石（奥斯滕）透镜体组成。三个测量和采样部分产生了多样化的化石动物群，主要是三叶虫，特别是不生类，和原始Anabarochinina。化石保存完好，但仅限于臭石。古德姆的 L. laevigata 区域包括几种地理上广泛分布的关键不可知物种，特别是 Tomagnostella sulcifera、Clavagnostus spinosus、Glaberagnostus altaicus、Lejopyge laevigata 和 L. armata。斯堪的纳维亚半岛的 L. laevigata 区域在此扩展至包括传统的 Solenopleura？ brachymetopa 带，其下边界由 L. laevigata 的 FAD 定义。三叶虫证据表明，斯堪的纳维亚 L. laevigata 地带的上部与中国和其他地方的 Proagnostus ballbus 地带大致相关。
The middle Cambrian Lejopyge laevigata Zone is poorly exposed in Scandinavia. Both this zone, however, and the succeeding Agnostus pisiformis Zone are well exposed at a classic locality at Gudhem, Västergötland, south-central Sweden. The sequences consist of finely laminated alum shale with scattered stinkstone (orsten) lenses. Three measured and sampled sections yielded a diverse fossil fauna, dominated by trilobites, in particular agnostoids, and the bradoriid Anabarochilina primordialis. Fossils are excellently preserved but restricted to the stinkstones. The L. laevigata Zone at Gudhem includes several geographically widespread key agnostoid species, notably Tomagnostella sulcifera, Clavagnostus spinosus, Glaberagnostus altaicus, Lejopyge laevigata and L. armata. The L. laevigata Zone in Scandinavia is here extended to include the traditional Solenopleura? brachymetopa Zone, and its lower boundary is defined by the FAD of L. laevigata. Trilobite evidence shows that the upper part of the Scandinavian L. laevigata Zone approximately correlates with the Proagnostus bulbus Zone of China and elsewhere.