Migration

The Migration group contains modules for seismic imaging and velocity model analysis in both time and depth domains. The group covers Kirchhoff pre-stack time and depth migration, reverse-time migration (RTM) in 2D and 3D, PSDM and PSTM imaging, anisotropy parameter estimation (VTI and HTI), velocity model building and depth conversion, and a range of supporting utilities for travel-time calculation, velocity selection, and Q-factor estimation.

The following modules are available in this group:

Azimuthal Kirchhoff PreSTM-file in/out-migration — performs azimuthally sectored Kirchhoff pre-stack time migration, preserving azimuthal amplitude information for anisotropy analysis.

Check Rikatti equations method — validates the Riccati-equation-based ray tracing used in migration travel-time computation.

Convert time to depth data — converts a time-domain seismic dataset to the depth domain using a velocity model.

Delta and V vertical calculation — estimates VTI anisotropy parameters delta and vertical P-wave velocity from migrated gathers or stacking velocity analysis.

Depth velocity builder (horizontal) — builds a horizontally layered depth velocity model for use in depth migration and depth conversion workflows.

Estimate Q factor — estimates the seismic quality factor Q from spectral attenuation of seismic traces for use in Q-compensation migration.

HTI delta estimation — estimates the HTI (horizontal transverse isotropy) anisotropy parameter from azimuthal amplitude variation in migrated gathers.

Kirchhoff PreSTDeMigration-file in/out-migration — performs Kirchhoff pre-stack time de-migration, converting migrated gathers back to common-offset data space.

Kirchhoff PreSTM-file in/out-migration — performs Kirchhoff pre-stack time migration reading data from and writing results to disk files, suitable for large-volume production runs.

Kirchhoff time demigration — reverses a Kirchhoff time migration to restore data to the unmigrated domain for re-migration with an updated velocity model.

PSDM Imaging — performs pre-stack depth migration (PSDM) imaging using a depth velocity model to produce depth-domain common-image-point gathers.

PSTM Imaging selector 2D (velocity/angle/offset) — applies 2D Kirchhoff PSTM with output selection by velocity, angle, or offset for residual velocity analysis.

RTM 2D — performs 2D reverse-time migration using finite-difference wave propagation for high-fidelity imaging of complex structures.

RTM depth — performs 3D reverse-time migration in the depth domain.

RTM3D depth distributed — performs distributed 3D reverse-time migration using multiple nodes for large-scale depth imaging.

RefBasedStat — computes refraction-based static corrections for input to migration and stacking workflows.

Refill TT — fills missing travel-time table values by interpolation to ensure complete coverage for migration operators.

Stretch depth to time — converts a depth-domain dataset back to the time domain using a velocity model, performing the inverse of time-to-depth conversion.

Time table calculation for tomo update — recomputes travel-time tables after a tomographic velocity model update for use in subsequent migration iterations.

Time tables calculation — computes ray-based travel-time tables from a velocity model for use in Kirchhoff migration operators.

TT viewer — provides interactive visualisation of travel-time tables for QC of migration operators before running the full migration.

VTI epsilon estimation — estimates the VTI anisotropy parameter epsilon from long-offset moveout residuals in pre-stack migrated gathers.

Velocity selector - Kirchhoff PreSTM Engine — selects and applies the RMS velocity function used as input to the 2D Kirchhoff PSTM operator.

Velocity selector 3D - Kirchhoff PreSTM Engine — selects and applies the 3D RMS velocity model used as input to the 3D Kirchhoff PSTM operator.