地层程序既有实用价值,又有理论意义,它要求精确地使用语言。国际间的了解在这门学科中是极其重要的。由于英语现在已被如此广泛地运用于科学,所以讲英语国家的地质工作者就更有责任来弄清含义。从十九世纪末叶召开的一些早期的地质会议和许多国家的地层规范颁布以来,地层分类的概念几十年来一直在演变着。这方面的国际机构——国际地科联的地层委员会和所属的地层划分分会——终于公布了“国际地层指南”。这一课题涉及的内容是由包括在“指南”中的一长串极为有用的参考文献目录来表达的。伦敦地质学会自己的地层委员会在国际方面的特殊贡献是:为建立一致同意的年代地层学而设法澄清层型剖面中的底界定义这一重要程序。地层委员会已经发行了一系列刊物,其 Stratal procedures have both practical and theoretical meanings, and require accurate use of the language. International understanding is of paramount importance in this discipline. As English is now so widely used in science, geologists speaking English-speaking countries are even more responsible for clarifying what they mean. The concept of stratigraphic classification has evolved over the decades since the early geological conferences of the late nineteenth century and the promulgation of stratigraphic norms in many countries. International agencies in this field, the FLC Stratigraphic Commission and the associated Stratigraphic Branch - finally published the International Stratigraphy Guide. The topics covered in this Question are expressed in a long list of extremely useful bibliographies included in the Guide. A special international contribution by the LSE’s own formation committee is to try to clarify the definition of the bottom boundary in the stratotype profile for the establishment of agreed geochronostratigraphy. The formation commission has issued a series of publications, which