The invention provides a target-stratum-frequency-spectrum-based design method of a non-linear scanning
signal of a vibroseis. The method comprises: optimizing an exploration area profile,
logging, or typical single gun and carrying out a target stratum
frequency spectrum analysis, and carrying out fitting to obtain a
frequency spectrum curve A(f); according to a frequency and
energy requirement of an exploratory area, designing a starting frequency, a scanning length, and a start-stop
slope length; solving a
time function t(f) corresponding to each sampling frequency; carrying out inverse transformation on the time functions t(f) to obtain time frequency functions f(t); and carrying out integration on the time frequency functions f(t) to calculate an
instantaneous phase, thereby calculating a sinusoidal vibroseis scanning
signal. According to the invention, with the generated vibroseis scanning
signal, objectives of improvement of the energy and
signal to noise ratio of the target stratum of the exploratory area can be achieved. Especially for the complicated work area, the scanning
signal design can be realized according to the different buried depths of target stratums at different zones of the work area, thereby improving the quality of seismic data excited by the vibroseis.