江苏水网地区高分辨率三维地震采集技术研究

The high-resolution 3-D seismic acquisition in Jiangsu dense waterway net

江苏石油勘探局地球物理勘探处,江苏洪泽 223125

Jiangsu Geophysical Prospecting Company, Hongze 223125, China

江苏地区水网密布,地质构造复杂.采用常规三维地震勘探技术进行数据采集.所得资料的分辨率较低.不能满足岩性圈闭研究的需要。针对这一问题.进行了地层吸收衰减、环境干扰、激发和接收因素等研究。研究表明.采用井深9 m、高密度4 kg炸药激发可以获得较高信噪比和分辨率的记录;采用中频检波器接收的信号主频高、频带宽;采用垂直测线方向的6串2并,组内距1 m,行距1 m的矩形面积组合,可有效压制环境噪音.提高信噪比。现场处理采用地震信号增强、频宽拓展及速度分析等技术,使目的层的有效频宽达到了10～90 Hz,主频达到了40 Hz,大大提高了资料的信噪比和分辨率。

The surface is densely covered with waterway net in Jiangsu. The geologic structure is complex. The resolution from general 3-D seismic acquisition technology is low and cannot meet the needs of the interpretation of lithological traps. Based on the theory analysis and examination of exploding and incepting factor, the exploding factor for high-resolution seismic acquisition suitable for dense waterway net are adopted. Using intermediate frequency detector and the great dynamic range digital seismograph, the shot and receiver array is optimized Processing with special module, enhance to seismic signal and frequency span, analyzed the velocity etc. High Signal-to-Noise Ratio and high resolution of 3-D seismic data are acquired. The effective frequency bandwidth of target is 10-90Hz and the main frequency is 40Hz. The technique of high-resolution seismic acquisition suitable for Jiangsu dense waterway net is build.