A Standard Biostratigraphic Sequence for the Devonian of Western North America

约翰逊对美国西部泥盆纪的研究涉及六个方面的努力。1.腕足类系统学：描述和图解腕足类三个新属。2.腕足类占主导地位的群落；内华达州泥盆纪已知的30多个群落将根据它们在已建立的时间-岩石框架中的相对位置进行分析。这将是过去25年收集的数据的综合。3.将通过对内华达州尤里卡县羚羊山脉北部测量剖面的详细采样，了解艾菲尔期、弗拉斯期晚期和法门期早期的牙形刺和腕足类序列。4.通过对大量牙形刺测年的测量剖面岩石的研究，解释了北羚羊山脉吉韦特期和法门期晚期-法门期岩系的沉积史。吉维斯蒂安事件的顺序就像加拿大的凯格河屏障一样。上法拉世灰岩中的石英砂来自西方。5.它旨在分析过去12年收集的数据所推覆的罗伯茨山脉前缘的地质情况。6.将编写一份关于美国西部古生代的审查文件。

Johnson's research in the Devonian of the western U.S. involves six areas of endeavor. 1. Brachiopod systematics; three new brachiopod genera will be described and illustrated. 2. Brachiopod-dominated communities; more than 30 communities known in the Devonian of Nevada will be analyzed in terms of their relative positions in an established time-rock framework. This will be a synthesis of data collected during the last 25 years. 3. The Eifelian, late Frasnian, and early Famennian conodont and brachiopod sequences will be made known by detailed sampling of measured sections in the northern Antelope Range, Eureka County, Nevada. 4. The depositional history of Givetian and late Frasnian-early Famennian rock sequences in he northern Antelope Range will be interpreted by study of rocks in a number of measured sections that are well dated by conodonts. The Givetian sequence of events is like that of the Keg River barrier of Canada. Quartz sand in upper Frasnian limestones is of western derivation. 5. It is intended to analyze geology along the frontal margin of the Roberts Mountains thrust from data gathered during the last 12 years. 6. A review paper will be prepared on the Paleozoic of the Western United States.