Study On Fractal-based For Picking First Arrivals On Seismic Traces

Study On Fractal-based For Picking First Arrivals On Seismic TracesABSTRACTIt is always a basic and important question to detect first arrivals on seismic traces .In the survey with clean record background and with simple wave forms from first arrivals ,We are usually able to pick the accurate first arrivals by regular methods such as energy ratio algorithm ,etc .but in the complex survey ,Because the first arrival wave forms vary greater and the various waves interfere each other ,So the effect for picking first arrivals is to be influenced .With the development of the seismic exploration ,More mountainous data is to be acquired for recent years .Thus finding more accurate methods for picking first arrivals become urgent to us.Two fractal-based algorithm for detecting first arrivals on seismic traces are presented in this paper by studying the variation in fractal dimension along the seismic trace .(l)A fractal-based algorithm for detecting first arrivals (2) A algorithm based on fractal and wavelet for detecting first arrivals.In the process of analyzing, A lot of test for picking first arrivals are conducted with data from the various area or from the various ratio of signal to noise and proved that two fractal-based algorithm for picking first arrivals is effective and practicable.