地质年代测定原理质疑——古水力学的一种新方法(英文)  

GEOLOGICAL DATING PRINCIPLES QUESTIONED Paleohydraulics:a new approach

作　　者：Guy Berthault 

出　　处：《大地测量与地球动力学》2002年第3期19-27,共9页Journal of Geodesy and Geodynamics

摘　　要：作为地质年代测定的基础是史泰侬 (Stenon)于 17世纪提出的三原则 ,即 :叠加、连续性和原始水平性。这些原则又源于一项沉积学假设 :土壤下的各层都是古老连续沉积的地层。因而地层学是以沉积学资料为基础的。现根据连续观察和实验室的实验结果认为 :史泰侬的地层学模型与实验数据不符 ,因为他忽略了沉积学中的主要因素 :流动及其时序效应。沉积过程可以分为 3个阶段 :冲刷、搬运和沉积物的积淀 ,而非静态的液流正是搬运的因素。史氏仅考虑到第 3阶段———沉积 ,且假设液流的速度为零。模拟了由不同颗粒度和具有不同速度生成的诸多沉积层的构造 ,将液流的时序重新组合到作者的科学见解的范围内 ,而这对于在沉积学 ,地层学和地质年代测定的相互链接的顺序中是必不可少的。作者引入古水力学作为地质年代确定的新方法 ,从而把这个链条的两端连接起来 ,而把对喷发岩的放射年代测定法视作非常规的方法。总之 ,古水力学这一新方法导致了实验沉积学的建立 。Stratigraphy, the basis of geological dating was founded in the ⅩⅦ century on the three well known principles assumed by Stenon: superposition, continuity, original horizontality. These three principles came from a postulate in sedimentology: layers of sub soil are strata of ancient successive sediments. Stratigraphy is, therefore,based upon data acquired from sedimentology.On the basis of successive observations and experiments this paper realises and verifies that Stenon's stratigraphic model was not in line with experimental data because it had 'overlooked' the major variable factor of sedimentology: the current and its chronological effects. The sedimentological process can, effectively, be divided into three phases: erosion, transport and deposit of sediments,with the liquid current being the vector of transport. Stenon's stratigraphy only took into account the third phase of sedimentology, the deposit, implicitly assuming the velocity of current to be nil. The author of this paper simulated the constitution of layers of sediment generated at variable velocities from differing granulometries.He reincorporated the chronology of currents into the field of his scientific investigations, as it was indispensable for modelling all the interlinked sequences in sedimentology, stratigraphy and geological dating.The author introduced paleohydraulics as the new approach to geological dating to integrate the two ends of the chain,and refers to radiometric dating measures of eruptive rocks recognised as aberrant in relation to the date of eruption.Generally speaking,the new approach paleohydraulics brings about the establishment of experimental sedimentology and Stenon's ⅩⅦ century postulate and principles are no more than interpretations that must be carefully checked with data from observation and the laboratory.

关 键 词：地质年代测定 古水力学 土壤 沉积学 时序效应 叠加 地层学 

分 类 号：P597[天文地球—地球化学]