The microfauna of the Early-Middle Cambrian boundary interval of Nevada and south-east California (western Laurentia)

小壳化石(SSF)为生物地层学和生态地层学、古生物地理学以及寒武系第二系和寒武系第三系(传统的早-中寒武世界线)沉积序列的对比提供了基本的潜力。特别是在缺乏生物地层学相关分类群(古生物或三叶虫)的沉积序列中，它们提供了重要的、往往是唯一的古生物地理学和生物地层学信息。尽管在世界范围内大多数早-中寒武世序列中，对SSFS的认识已经从根本上增加了，但它对劳伦斯剖面的数据基础仍然很差。拟议项目的核心是对内华达州和加利福尼亚州东南部早-中寒武世界线区间的SSFS进行首次详细调查。该地区的特点是最完整和最好暴露的早中寒武世序列，因此提供了丰富和多样的微型动物。关于早-中寒武世SSFS的分类学、古生物学以及区域和地层分布模式的知识有望异常增加。收集数据库中的分类群将有助于实现生物地层对比的目标，并有助于重建迁徙路径。

Small shelly fossils (SSFs) offer a fundamental potential for bio- and ecostratigraphy, paleobiogeography, and the correlation of sedimentary successions covering the Cambrian Series 2 and Cambrian Series 3 interval (the traditional Early-Middle Cambrian boundary interval). Especially in sedimentary succession characterized by the absence of biostratigraphical relevant taxa (archaeochyathans or trilobites) they deliver important and often the only paleobiogeographic and biostratigraphic information. Whereas the knowledge in SSFs has been fundamentally increased for most of worldwide Early-Middle Cambrian successions, its data base is still very poor for Laurentian sections. Central to the proposed project is the first detailed investigation of SSFs of the Early-Middle Cambrian boundary interval of Nevada and south-eastern California. This region is characterized by the most complete and well exposed Early-Middle Cambrian successions of the United States, thus offering an abundant and diverse microfauna. An exceptional increase in knowledge about taxonomy, paleobiology, and regional and stratigraphical distribution patterns of Early-Middle Cambrian SSFs is expected. The collection of taxa in a database will support the aim to achieve a biostratigraphic correlation and help to reconstruct migration pathways.