Abstract:Geophone array is used to suppress random noises and regular noises and improve signal to noise ratio,especially in those prospects with low signal to noise ratio.Array parameter design is commonly performed under the assumption that seismic waves are harmonic waves at a specific frequency.Element interval,number of arrays,weighing factor,and time delay have not been taken into overall consideration; this results in significant low-pass filtering and distorted AVO effects.We discuss the relations among above 4 parameters and orientation factor at complex frequencies.To calculate the theoretical signal to noise ratio,we formulate an equation and then take it as the objective function for array parameter design through global optimization.As per model and field data tests,linear noises and random noises could be greatly reduced using the time-delay weighted arrays with above 4 optimized parameters; the behavior of low-pass filtering and AVO distortion could also be remedied.
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