Study of the Early Cretaceous (Albian) Faunas of the Cottonwood District

该项目将建立一个现代分类学基础， 生物地层学，地理学，以及中世纪的演化 太平洋白垩纪（Albian）动物群（主要是菊石） 并将完善生物地层标准 在棉白杨区， 北方加州。 详细的参考标准是 了解古生物学问题的先决条件 生物相、地理学和演化模式， 年代地层学 它也需要地层和 需要高度生物地层学的构造问题 分辨率 这样的研究将：1）阐明微观结构， 形态学和个体发育特征， 菊石分类群; 2）将使一些进化序列， （3）被认可的模式;（3）允许检查 关于菊石演化的假说由德国，俄罗斯， 和法国作家; 4）使较低的精细相关性 太平洋沿岸的白垩纪地层 欧洲的剖面和起源于特提斯的序列 航道，例如高加索，印度; 5）使古生物地理和 生物面部的解释，其中一些现在被掩盖， （6）更好地理解事物; 该地区及其动物群的历史; 7）允许更平衡的 北美白垩纪历史的观点; 8）允许 对白垩纪中期灭绝事件的评估

The project will establish a modern taxonomic base for studies of biostratigraphy, biogeography, and evolution of the middle Cretaceous (Albian) faunas (predominantly ammonites) of the Pacific rim of North America and will refine the biostratigraphic standard of reference for this interval in the Cottonwood District of northern California. A detailed standard of reference is prerequisite to an understanding of paleobiological problems of biofacies, biogeography and patterns of evolution, and for chronostratigraphy. It is also needed for stratigraphic and structural problems requiring a high degree of biostratigraphic resolution. Such a study would: 1) elucidate the microstructural, morphologic, and ontogenetic characteristics of many unstudied ammonite taxa; 2) would enable some evolutionary sequences to be recognized and their patterns to be examined; 3) permit examination of hypotheses of ammonite evolution proposed by German, Russian, and French writers; 4) enable a refined correlation of the Lower Cretaceous strata around the Pacific rim with the classical sections in Europe and with sequences originating in the Tethyan seaway, e.g. Caucasus, Indian; 5) enable paleobiogeographic and biofacial interpretations some of which are now masked by antiquated taxonomy; 6) permit a better understanding of the history of the region and its faunas; 7) permit a more balanced view of the Cretaceous history of North America; 8) permit assessment of proposed mid-Cretaceous extinction events.