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当前国际志留系研究正面临着新问题,即如何对国际地层委员会业已批准、却存在较大问题的“志留系统、阶”某些界线层型进行“再研究”。最近 Holland et al.(2003)撰文认为这样的“再研究”是对志留纪地层框架的破坏和瓦解。其实,国际志留系分会作出的“再研究”决定,并没有对20世纪80年代就取得一致意见、被国际地层委员会批准的志留系标准分类做修改,而仍使用“一系、四统”标准,即兰多维列统(Llandovery Series)、温洛克统(Wenlock Series)、罗德洛统(Ludlow Series)和普里道利统(Pridoli Series)。但是,对志留系底界和温洛克统底界的“再研究”却很有必要。最新的研究表明,对志留系底界原层型可以不动,但其原点位则需变更,即从 Parakidograptus acuminatus 带的底界下移到 Akidograptus ascensus 首现为标志的该带底界。扬子区剖面为全球奥陶系—志留系界线地层的对比提供了重要的依据。对于温洛克统底界,原英国威尔士的层型剖面和点位不具备基本条件,很可能要从其他地区寻找连续的、研究程度高的剖面来解决这些问题。科学在发展,地层学在不断进步。“再研究”能在追寻地层研究的“稳定性”和“精确性”的过程中,提高全球高分辨率的地层对比水平。
At present, the study on international Silurian is facing a new question, that is, how to conduct “re-study” on some “boundary lines” of the Silurian system, which is a problem that has been approved by the International Stratigraphy Commission but has major problems. More recently, Holland et al. (2003) argue that such “re-research” is the destruction and disintegration of the Silurian stratigraphic framework. In fact, the decision made by the International Silurian Branch not to make any revisions to the standard classification of Silurian approved by the International Stratigraphy in the 1980s and still use the “ , The four systems ”standard, namely the Llandovery Series, the Wenlock Series, the Ludlow Series and the Pridoli Series. However, it is necessary to study the “re-research” of the bottom boundary of Silurian and the bottom of the Rohivolt System. The latest research shows that the bottom layer of the Silurian can not change its original shape, but its origin needs to be changed. That is, it changes from the bottom boundary of the Parakidograptus acuminatus zone to the bottom boundary of the first appearance of the Akidograptus ascensus. The Yangtze section profile provides an important basis for the comparisons of Ordovician-Silurian boundary strata in the world. For the Rohivoden bottomography, the stratigraphic profiles and locations of the original Welsh, England, do not have the basic conditions and are likely to find continuous, highly studied profiles from other regions to solve these problems. Science is developing, stratigraphy is making progress. “Re-research ” can improve the global high-resolution stratigraphic correlation in the search for “stability” and “accuracy” of stratigraphic studies.