浅层折射隐层问题研究

Research on subtle layer in shallow refraction survey.

浅层折射法常被用来进行地震勘探静校正资料采集和工程地质调查。然而,由于折射隐蔽层的存在,给浅层折射资料解释成果带来了很大误差。这个问题,以往常常被人们所忽视。本文首先引入了隐层范围函数 R_(?)的概念。通过模型正演系统地分析了隐层存在的范围与本身地层参数以及上、下层地层参数的关系,总结了隐层可能存在的一般条件。然后,就隐层存在时对浅层折射资料用常规方法解释所导致的误差进行了讨论;最后提出了用内插法和平均速度求解隐层结构的两种方法,并指出了对浅层折射资料野外采集和解释工作中应注意的问题。文中提供的实例证明,用水文提出的解释方法可消除隐层对浅层折射资料解释成果精度的影响。

Shallow refraction is often used in seismic static correction data collection and engineering geology investigation.However,the existence of subtle layer causes se- vere error in shallow refraction interpretation.which was neglected by people. R the range function of a subtle layer is introduced here.The relation between subtle layer range and its formation parameter,overlying formation or underlying formation parameter is analysed by making forward modeling.The general condi- tions of a subtle layer existence are summarized briefly.The error is analysed which can be brought when people use usual methods to interpret the shallow refraction data in the area where subtle layer occurs.The article describes two methods for dis- covering subtle layer:interpolation method and mean velocity method.The author also points out the matters needing attention in collection and interpretation of shal- low refraction data.It is illustrated that the interpretation method in this article fa- vors removing the influence which subtle layer causes for shallow refraction inter- pretation accuracy.