Method for determining optimum seismic pulse

Claim 1

A method for determining a pulse configuration for an electrical control input signal to a vibratory seismic source comprising the steps of: operating a vibratory seismic source at a location to input oscillatory seismic energy into the ground over a sweep of frequencies where such frequencies are represented by first electrical signals; within said sweep of frequencies, determining the optimum amplitudes of energy input to the ground for a discrete nuMber of frequencies where the optimum amplitude is that amplitude short of an amplitude value that is distorted because the seismic source is overdriven and the determined amplitudes are expressed as second electrical signals; and recording said first and second electrical signals as a function of time for producing an electrical control input signal in terms of amplitude, frequency and time.

Claim 2

A method for determining a pulse configuration for an electrical control input signal to a vibratory seismic source comprising the steps of: operating a vibratory seismic source at a location to input oscillatory seismic energy into the ground over a sweep of frequencies where such frequencies are represented by first electrical signals; within said sweep of frequencies, determining the optimum amplitudes of energy input to the ground for a discrete nuMber of frequencies where the optimum amplitude is that amplitude short of an amplitude value that is distorted because the seismic source is overdriven and the determined amplitudes are expressed as second electrical signals; and recording said first and second electrical signals as a function of time for producing an electrical control input signal in terms of amplitude, frequency and time.

Claim 5

A method for obtaining an electrical control input signal for a vibratory seismic energy generator comprising the steps of: oscillating a hydraulically operated vibratory seismic energy generator at a first frequency and a first hydraulic driving pressure at a first location for developing an energy input of said seismic source to the ground at a first frequency and an amplitude functionally related to said hydraulic driving pressure; detecting the amplitude of the energy input to the ground at said first frequency and producing a first electrical signal as a function of such amplitude and said frequency; increasing the hydraulic driving pressure at said first frequency until said first electrical signal becomes distorted because the generator is being overdriven; recording said first electrical signal at an amplitude level below the occurrence of a distorted first electrical signal; changing the frequency to a second frequency after recording of the first electrical signal; detecting the amplitude of the energy input to the ground at said second frequency and producing a second electrical signal as a function of such amplitude and said second frequency; increasing the hydraulic driving pressure at said second frequency until said second electrical signal becomes distorted because the generator is being overdriven; recording said second electrical signals at an amplitude level below the occurrence of a distorted second electrical signal; repeating the steps of changing the frequency, detecting the amplitude, developing electrical signals and recording the signals; and deriving from said electrical signals an electrical control input signal as a function of maximum amplitude, frequency and time.

Claim 6

A method for obtaining an electrical control input signal for a vibratory seismic energy generator comprising the steps of: oscillating a hydraulically operated vibratory seismic energy generator at a first frequency and a first hydraulic driving pressure at a first location for developing an energy input of said seismic source to the ground at a first frequency and an amplitude functionally related to said hydraulic driving pressure; detecting the amplitude of the energy input to the ground at said first frequency and producing a first electrical signal as a function of such amplitude and said frequency; increasing the hydraulic driving pressure at said first frequency until said first electrical signal becomes distorted because the generator is being overdriven; recording said first electrical signal at an amplitude level below the occurrence of a distorted first electrical signal; changing the frequency to a second frequency after recording of the first electrical signal; detecting the amplitude of the energy input to the ground at said second frequency and producing a second electrical signal as a function of such amplitude and said second frequency; increasing the hydraulic driving pressure at said second frequency until said second electrical signal becomes distorted because the generator is being overdriven; recording said second electrical signals at an amplitude level below the occurrence of a distorted second electrical signal; repeating the steps of changing the frequency, detecting the amplitude, developing electrical signals and recording the signals; and deriving from said electrical signals an electrical control input signal as a function of maximum amplitude, frequency and time.

Claim 8

The method for obtaining an electrical control input signal for a vibratory seismic energy generator comprising: operating a vibratory seismic source at a location where a seismic survey is desired and producing oscillatory motion over a sweep of frequencies; detecting the frequency and amplitude of the energy input of said seismic source to the ground at discrete frequencies and producing first electrical signals; for each discrete frequency, comparing the first electrical signals to a reference signal; for each discrete frequency, increasing the amplitude of said energy input of said seismic source to the ground so long as a comparison of said signals indicates that the amplitude of the energy input is not distorted by overdriving of the seismic source; for each discrete frequency, storing the first electrical signal prior to each increase in amplitude of said energy input to the ground; for each discrete frequency, recording said stored electrical signal whenever the amplitude of said energy input to the ground becomes distorted due to overdriving of the seismic source; and for each discrete frequency, upon recording of said stored signal, increasing the frequency of said energy input to the ground.

Claim 9

The method for obtaining an electrical control input signal for a vibratory seismic energy generator comprising: operating a vibratory seismic source at a location where a seismic survey is desired and producing oscillatory motion over a sweep of frequencies; detecting the frequency and amplitude of the energy input of said seismic source to the ground at discrete frequencies and producing first electrical signals; for each discrete frequency, comparing the first electrical signals to a reference signal; for each discrete frequency, increasing the amplitude of said energy input of said seismic source to the ground so long as a comparison of said signals indicates that the amplitude of the energy input is not distorted by overdriving of the seismic source; for each discrete frequency, storing the first electrical signal prior to each increase in amplitude of said energy input to the ground; for each discrete frequency, recording said stored electrical signal whenever the amplitude of said energy input to the ground becomes distorted due to overdriving of the seismic source; and for each discrete frequency, upon recording of said stored signal, increasing the frequency of said energy input to the ground.