基于炸药激发子波特性选择激发井深

Choosing shooting depth based on characteristics of explosive-activated wavelet.

在激发井深选择上,应根据不同的勘探目标,利用炸药激发子波定量优选激发井深。文中针对虚反射研究激发子波的拾取及运动学、动力学特点和频率特性,并得出以下认识:①在虚反射界面以下激发,速度值不变,陷波点频率和峰值频率随着激发井深的增加向低频方向移动;②针对高分辨率勘探,要选择较小的调谐深度,可以得到较高的峰值频率;针对深层勘探,可以选择合适的频率所在的调谐深度,在该深度激发可得到能量较强的激发子波。利用文中方法在BQ地区进行了炸药震源子波提取和对比、单炮及剖面分析,结果表明,新采集地震资料的分辨率得到明显提高,其剖面主频较原资料提高了5～10Hz。

Choosing shooting depth was discussed in this paper. Based on different exploration objectives, explorative-activated wavelets were used to quantitatively optimize shooting depth. Regarding the ghost reflection the wavelet's picking-up and its kinematics and feature and frequency, the characteristics in Kinetics were studied, and the following recognition were obtained:(1)if shot activated under the ghost reflector, the velocity is constant,notch frequency and peak frequency will move to lower frequency with the increase of shooting depth. (2)regarding high resolution exploration,smaller tuning depth should be chosen so that higher peak frequency can be obtained; regarding deep exploration,it is needed to choose tuning depth which is in accordance with proper frequency so that the activation wavelet with stronger energy can be obtained in the depth.Utilizing the method to extract the explosive source wavelet,to correlate the wavelets and to analyze single shot and sections,the results show that the resolution of the latest acquired seismic data was improved,and the dominant frequency of the seismic data was raised 5~10Hz compared with the old seismic data.