Article,
Determination of the signature of a dynamite source using source scaling. Part 2: Experiment
Geophysics, 58 (8): 1183--1194 (Aug 1, 1993)
DOI: 10.1190/1.1443502
Abstract
In April 1990 we performed an experiment in the Netherlands to test
the theory of the determination of the signature of a dynamite source
using the scaling law. The theory says that the source signature
may be determined from the recorded seismic data using two shots
of different charge size at the shotpoint; we used 125 g and 500
g charges. The theory was put at risk with a 250-g test charge at
each shotpoint. According to the theory, the test record should be
different from the other two and, apart from the noise, should be
predictable from them. This experiment was repeated 95 times at approximately
50 m shotpoint intervals, using a 240-channel recording system. The
results corroborate the theory within an acceptable error. The second-derivative
of the volume injection function was extracted as the source signature;
it varied slightly from shot to shot and was minimum phase. This
new method of seismic data acquisition allows the signature of the
dynamite source to be obtained from the data, uncontaminated by the
earth, and avoids the assumptions that must be made in statistical
wavelet estimation methods. If there is good shot-to-shot repeatability,
the second shot is only needed occasionally for calibration.
