EmphaSeis

Broadband Vibroseis Sweep

EmphaSeisTM intelligently tailors vibroseis sweeps to extend bandwidth while working within the mechanical and hydraulic constraints of the vibrator. These proprietary* customized broadband sweeps can add a combination of low and high frequencies to provide better wave penetration, finer images and improved single- and multi-component reservoir characterization.

The ability of vibroseis sources to produce a controlled, broadband seismic source wavelet is limited by a range of constraints related to the complex behaviour of the mechanical and hydraulic systems of the vibrator and its coupling.

EmphaSeis gets the most from any vibrator by using customized sweeps designed to build up energy at low and high frequencies while keeping the vibrator operating well within its capabilities.


Linear sweep stack and filter panels EmphaSeis stack and filter panels

Slide to compare

The raw stack (on the left of the images) and the filter panels (3-7;7-14;14-72 Hz) show that the EmphaSeis sweep increases the low frequency content of the stack without reducing the amount of energy in the rest of the bandwidth. Data courtesy of Khalsa Production Company/ Apache.


Features:

  • Customizable non-linear broadband vibroseis sweep which can achieve 5 octaves or more 
  • Additional octave or more of low frequencies for better penetration
  • Intelligently designed vibrator-specific proprietary* sweep and sweep tapers accounting for: 
    • Mass stroke constraint 
    • Hydraulic flow constraints 
    • Servo-valve limit

*Patents Pending

Benefits:

  • High-resolution broadband images to help resolve thin beds 
  • Better penetration and imaging of deep and shallow targets 
  • Improved reservoir characterization 
  • Improved bandwidth converted wave data for multicomponent analysis

Case Study

EmphaSeis was recently deployed in Egypt on an existing vibroseis crew. Using the same equipment and the same sweep length (18 seconds) EmphaSeis was able to deliver an additional octave of low-frequency bandwidth from 4-6 Hz.

Linear sweep Drive Level


Drive Level (kN) vs Time (s) of the Linear sweep (6-72 Hz, in blue) and of the  EmphaSeis sweep (4-72 Hz, in green). Note the tapered build-up of the low frequencies on the non-linear EmphaSeis sweep. In this case, the high frequencies were also tapered to reduce vibrations on the gravelly terrain.

EmphaSeis sweep Drive Level

The stack images show a subtle increase in the low-frequency energy which is clearly visible on the amplitude spectrum. These low frequencies contribute to the signal recovered from deeper events, improving continuity and coherency for interpretation. They will benefit various processing steps such as statics and noise attenuation and also improve the quality of reservoir models from seismic inversion.

Amplitude spectrum of the measured ground force

Comparison of the 18 s sweeps showing amplitude spectra of the measured ground force. EmphaSeis adds an additional octave of bandwidth compared to the conventional linear sweep.

Onshore - CleanSweep

CleanSweep

Leverage the broad frequency content of your data with low frequencies, free of harmonic noise, for more reliable inversion and interpretation.

Onshore - UltraSeis

UltraSeis

Enabling quantitative interpretation for onshore reservoir development. Update your reservoir model from this fully integrated solution.

Onshore - General Geophysics

General Geophysics

Mastering the full spectrum of geophysical techniques to design customized geophysical surveys for a wide range of industries.

Onshore (Land)

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