等时体与定量地层学  

Chronosome and Quantitative Stratigraphy

作　　者：Cedric M. Griffiths(BP Research, BP/Sutoil, Ranheimsveien 10, N-7004 Trondheim , Norway)Ulf Nordlund(Institute of Petroleum Technology and Applied Geophysics, University of Trondheim, N-7034 Trondheim ,Norway) 

机构地区：[1]特隆赫姆大学石油工艺与应用地球物理学院

出　　处：《江汉石油学院学报》1996年第4期1-8,共8页Journal of Jianghan Petroleum Institute

摘　　要：年代线限定的岩石体（即等时体ｃｈｒｏｎｏｓｏｍｅ）的三维作图构成了地下岩石性质和生物地层学定量预测的基础。高分辨率地震资料能够提供可作图的反射单元，其垂向分辨率可达１０～２０ｍｓ，对于第三系而言，相当于１０～２０ｍ；侧向分辨率在三维勘探时可达１０ｍ，而在二维勘探时则在５００ｍ以上。假定地震反射面是等时的，并将反射单元标绘成等时体，则每个等时体是地质时间段和古地理位置的特定组合。它们通常由次一级的等时体组成，并可以组合成高一级的等时体。因此，等时体概念与时间和标度无关。地震地层学构成了一个成因框架，在这个框架中任何设定位置的等时体的垂向发育均与区域性的或者全球性的地质过程有关。目前，地震地层学的概念和术语大多是在二维情况下定义的，而全盆地沉积物分布却是三维的。只有通过等时体三维作图，才能确定等时体形状、位置和容量间的预测关系，这种关系无论对盆地内定量地层学的实际运用还是因果关系的理论分析都是必需的。The three-dimensional mapping of time-bounded bodies of rock (chronosome ) forms the basis of quantitative prediction of both rock properties and biostratigraphy in the subsurface. High resolution seismic data can provide mappablereflection-bounded units (RBU)s) with a vertical resolution of 10 to 20 ms two-way-time(approximately 10-20 m in Tertiary sediments). Lateral resolution varies from 10 m in a 3D survey, to 500 m plus in the case of a regional 2D survey. We can begin with theworking hypothesis that seismic reflectors are isochrons and map RBU,s to chronosomes.ash chronosome has a unique combination of geological time interval andpaleogeographical location. They are composed, generally, of lesser chronosomes below thecurrent observational resolution, and can be combined to form higher-order chronosomes.The chronosome concept is therefore both time, and scale independent. Seismicstratigraphy forms a genetic framework in which the vertical development of chronosomesat any given location can be related to regional and/or global processes. Current seismicstratigraphic concepts and terminologies are essentially two--dimensional, yet sedimentdistribution throughout a basin is, of couse, three-dimensional. Only by mappingchronosome development in three-dimentsional can one find the predictive relationships between shape, location and content that are needed both for practical application of quantitative stratigraphy and in the theoretical analysis of causative processes within thebasin.

关 键 词：地震地层学 定量地层学 生物地层学 

分 类 号：P53[天文地球—古生物学与地层学]