Cambrian Ichnostratigraphy of the Eastern Basin and Range and Western Rocky Mountains

拟议的研究侧重于遗迹化石(生物成因沉积构造)在大盆地东部和落基山脉西部的生物地层学和古环境研究中的应用。将研究下寒武统遗迹化石的四个方面：遗迹分类(系统分类)；生产方式(隧道、开沟等)；遗迹地层学；古生态和古地理意义。初步工作揭示了该地区遗迹化石的多样性和丰富性。此外，还存在各种潜在痕迹制造者的化石组合。将对节肢动物遗迹化石的分类进行修订，并将制定一套可在整个群体中一致应用的分类标准。考虑将包括形态模式、构造力学、结构类型(内生或表生)以及推断的痕迹标记物。将记录犹他州下寒武统和邻近地区内遗迹化石的地层分布，并将评估使用Cruziana和Rusophycus遗迹种建立的寒武纪-奥陶系地层模型的全球意义。将通过使用现代示踪器(例如昆虫和甲壳类)在沉淀物水槽和水族馆实验中检查样品和复制痕迹来调查Cruziana和Rusophycus的生产方式。将对遗迹相和岩相(或岩相)之间的关系进行表征，以记录早古生代的海底群落关系。遗迹化石还可以提供有关重要环境因素的详细信息，如底物浓度、盐度和沉积物缺氧。这些因素的分布模式允许推断当地的古地理，这将使现有的区域古地理模型比目前更清楚地定义。//

The proposed research focuses on the utility of ichnofossils (biogenic sedimentary structures) for biostratigraphy and paleoenvironmental studies in the eastern Great Basin and western Rocky Mountains. Four aspects of Lower Cambrian trace fossils will be studied: ichnotaxonomy (systematic classification); mode of production (tunnels, open furrow, etc.); ichnostratigraphy; paleoecologic and paleogeographic implications. Preliminary work has revealed a great diversity and abundance of ichnofossils in this area. In addition, diverse fossil assemblages of potential trace-makers also are present. A revision of the taxonomic classification of arthropod trace fossils will be undertaken, and a set of taxonomic criteria that can be applied consistently across the group will be formulated. Consideration will include patterns of morphology, mechanics of construction, the type of structure (endogenic or epigenic), and inferred trace-makers. The stratigraphic distribution of trace fossils within the Lower Cambrian of Utah and adjoining areas will be documented, and the global significance of Cambro-Ordovician stratigraphic models using ichnospecies of Cruziana and Rusophycus will be assessed. The mode of production of Cruziana and Rusophycus will be investigated by the examination of samples and the reproduction of traces in sediment flume and aquarium experiments, using modern trace-makers (e.g., insects and crustaceans). Characterization of relationships between ichnofacies and lithofacies (or lithotopes) will be made to document benthic community relationships in the early Paleozoic. Trace fossils also can furnish detailed information about important environmental factors, such as substrate consistency, salinity, and sediment anoxia. Patterns in the distribution of these factors allow local paleogeography to be inferred, which will allow existing regional paleogeographic models to be defined more clearly than they are at present.//