三维地震采集与分布式记录仪

3D seismic acquisition with distributed recording system.

本文分析了地震采集特别是地震记录仪的发展演变过程,指出:①瞬时动态范围才是真正的记录动态范围,浮点放大器并不能扩大记录动态范围。②目前流行的24位仪器实际具有的分辨率不足24位,而仅有20位。而且以20位的分辨率去配合一个108dB(相当于18位)的记录系统已经绰绰有余,更多的位数实属不必。可以考虑适当减少位数(如18位),以求大量节省成本同时也不降低记录精度。③在Δ-Σ的系统中加入任何模拟滤波器都是有害无益的。本文还进一步探讨了每道只用一个检波器进行采集的设想,提出了无线电检波器的概念,并预测了遥测地震仪的发展起势。

After making a detailed analysis about development of seismic acquisition, especially about development of seismic recording system, author of this paper made the following conclusions: 1) Instantaneous dynamic range is the real recording dynamic range, FPA(Floating Point Amplifier) can not be helpful for expanding the recording dynamic range. 2) The actual resolution of current seismic instrument with 24 bits A/D converter is only done 20 bits A/D converting, but this is enough to match a 108dB(18 bits) recording system. So it is not necessary to seek for high bits A/D converter. Maybe we should decrease some bits of A/D converter properly in order to save costs on the basis of keeping recording accuracy. 3) Anyanalog filter in Δ-∑ is useless. Furthermore, this paper puts forward a new concept--radio geophone,and a new idea--using only one geophone in each seismic channel to do the job of data acquisition. Author of this paper also discusses the developing trend of telemetry seismic instrument.