Preserved-traveltime smoothing method and device

A computing device for smoothing an original velocity model of a given subsurface such that a travel-time through the given subsurface is preserved, the computing device comprising:

• an interface configured to receive the original velocity model, wherein the original velocity model has a set of model parameters that determine a given parameterization and the original velocity model has velocity discontinuities at various depths;
• and
• a processor connected to the interface and configured to,
• select a non-zero sub-set of model parameters (v, δ, ε) from the set of model parameters of the given parameterization;
• convert the selected sub-set of model parameters (v, δ, ε) to composite parameters (n−1, n1, n3);
• smooth the composite parameters (n−1, n1, n3) by applying a convolutional filter (g) such that velocity moments (m−1, m1, m3) are preserved at the velocity discontinuities;
• and
• generate a smooth velocity model by converting the smoothed composite parameters into a smoothed sub-set of model parameters.

A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a processor, implement a method for smoothing an original velocity model of a given subsurface such that a travel-time through the given subsurface is preserved, the instructions comprising:

• receiving the original velocity model, wherein the original velocity model has a set of model parameters that determine a given parameterization and the original velocity model has velocity discontinuities at various depths;
• selecting a non-zero sub-set of model parameters (v, δ, ε) from the set of model parameters of the given parameterization;
• converting the selected sub-set of model parameters (v, δ, ε) to composite parameters (n−1, n1, n3);
• smoothing with a processor the composite parameters (n−1, n1, n3) by applying a convolutional filter (g) such that velocity moments (m−1, m1, m3) are preserved at the velocity discontinuities;
• and
• generating a smooth velocity model by converting the smoothed composite parameters into a smoothed sub-set of model parameters.