地震勘探仪器主要技术性能分析及改进探讨

Analysis and improvement of the main technical performance of seismic exploration instrument

通过对地震勘探仪器的主要技术性能的详细分析可以看出,无论是集中式数字地震仪还是24位Δ-∑A/D型遥测地震仪,都还记录不到大动态、高主频、宽频带的地震反射波,它们记录的中深层地震反射信号的瞬时动态范围均在60 dB左右.本文以水平层状介质的吸收衰减特性为依据,给出了智能程控型前置放大器和频谱均衡滤波器的数学模型.用智能程控型前置放大器补偿由于球面扩散所造成的振幅衰减;用频谱均衡滤波器补偿由于地层吸收所造成的振幅衰减.按此设计方案,研制真正具有大瞬时动态和高频提升功能的地震仪,对高分辨率地震勘探技术的进一步发展具有重要意义.

The detailed analysis of the main technical performance of seismic exploration instrument shows that neither the centralized digital seismograph nor the telemetry seismograph with 24-bit △-∑ A/D converter can record the seismic wave with large dynamic range, high dominant frequency and wide frequency band. The instantaneous dynamic range of reflection wave recorded by those instruments in the deep is about 60dB. In this paper, based on absorbing and attenual charateristics of horizontal stratified medium, the mathematical models of intelligent programmable pre-amplifier and spectrum equilibrium filter（SEF） are set up. The intelligent programmable pre-amplifier is set to compensate the amplitude attenuation casued by spherical diffusion, and SEF is set to compensate the amplitude attenuation casued by formation absorption. According to this design program, developing seismograph with large instantaneous dynamic range and high-frequency upgrade performance is significant to the further development of high resolution seismic exploration technology.