Waveform Tomography (Wavetomo)

In standard seismic processing, depth velocity is only one part of its workflow that generates images of seismic reflectivity as the final result. Due to the very low resolution of the seismic velocity model that applies standard processing methods, there has been a weak correlation between the image of a velocity distribution and the image of its seismic reflectivity.

Waveform Tomography processing can generate accurate depth velocity, indicated by strong correlation between the image of a velocity distribution and the image of its reflectivity. Depth velocity, with higher resolution, becomes an invaluable seismic asset and interpretation tool.

 

Strong correlation between velocity generated by waveform tomography (top),
reflectivity image (middle), and the true velocity solution (bottom) of Marmousi
complex structure model. (Waviv Tech)

See on Youtube click here

 

Waviv’s WaveTomo 2.0 uses advanced stochastic full waveform inversion that produces high resolution tomographic velocity images. Using intelligent stochastic modelling, our inversion technology is proven robust even to inaccurate initial velocity model. The result provides us more reliable velocity image as a seismic interpretation tool.

 

Main Applications of Waveform Tomography

 
Complex Structure Imaging

In complex structure area, seismic reflection usually gives poor quality image because of high difraction. To infer such complex structures, high resolution tomographic images can be used for reducing the ambiguities of a reflectivity image.

Accurate Migration Velocity

Waveform Tomography produces depth velocity that can be used as migration velocity. This velocity can overcome the ambiguity of time-to-depth velocity conversion.

High Resolution Tomography

With resolution four times higher than traveltime tomography, waveform tomography gives better imaging for cross-well refraction tomography, allowing detection of thin layers.

Time-Lapse Monitoring

Comparing two tomographic section with different aqcuisition time can be used as time-lapse monitoring. This is an invaluable tool for reservoir management and Enhanched Oil Recovery (EOR) project.

Pore Pressure Prediction

Using an accurate depth velocity, we can predict the distribution of pore pressures more accurately, therefore, can lower drilling risks.

Passive Seismic Depth Inversion

Usually, passive seismic methods can only generate the surface map of an area. By applying a virtual source concept, the waveform tomography can make use of passive seismic data for predicting the depth of a reservoir target and generate its depth image.