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

小壳壳化石（SSFs）为生物和生态地层学、古生物地理学以及寒武系2和寒武系3（传统的早-中寒武纪界线段）沉积序列对比研究提供了基础潜力。特别是在沉积演替中，由于缺乏与生物地层相关的分类群（古石虫或三叶虫），它们提供了重要的，而且往往是唯一的古生物地理和生物地层信息。尽管世界范围内大多数早-中寒武世序列的ssf知识已经得到了根本的提高，但其劳伦剖面的数据库仍然非常贫乏。拟议项目的核心是对内华达州和加利福尼亚州东南部早-中寒武纪边界区间的ssf进行首次详细调查。该地区是美国最完整、最暴露的早-中寒武纪演替区，因此提供了丰富多样的微动物群。预计在早-中寒武纪ssf的分类、古生物学、区域和地层分布模式方面的知识将有显著的增加。在数据库中收集分类群将有助于实现生物地层对比和帮助重建迁移路径。

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.