水网区基于小折射资料的激发分区设计方法探讨

Shooting parameters design on the data of the shallow refraction survey

东方地球物理公司采集技术支持部,河北涿州 072751

The data acquisition technical supporting department of CNPC Geophysical Prospecting Bureau, Zhuozhou 072751, China

采用小折射进行表层结构调查,依据解释的低、降速带速度和厚度进行激发井深分区设计是常用的方法。在水网区勘探常遇到潜水面以下的低速淤泥夹层,利用现有的小折射资料解释方法不能解释出这种夹层,使得这类地区小折射调查很难达到正确分区的要求。通过对小折射记录和地震记录的定量分析和对比,探讨了小折射资料属性、地震采集资料品质与表层结构的相关性,提出了综合利用小折射续至波资料进行表层结构调查的方法,并依据这些分析结果提出了相应的施工方法。

Designing shooting parameters by the result of the shallow velocity survey is a general method. However, we treated low velocity layer with silt in-terlayer frequently in areas covered with watercourses. Failing to investigate this silt interlayer through present shallow refraction method, it is hard for shallow refraction method to satisfy the requirement of shooting parameters design. Based on quantitative analysis of shallow refraction survey data and seismic data from field record, the correlation among attributes of shallow refraction data, quality of seismic data and weathered layer is discussed. A synthetic LVL survey method and workflow utilizing second arrivals of shallow refraction data is provided.