Near-surface model building is a crucial step in seismic imaging to ensure accurate interpretation of subsurface features. Here is a breakdown of the process: 1. **Data Collection**: - **First Arrival Picking**: Identifying the first seismic arrivals to estimate the near-surface velocity structure [[1](https://wiki.seg.org/wiki/Near-Surface_Modeling_and_Imaging)]. - **Seismic Surveys**: Gathering data through various seismic methods to capture detailed near-surface information [[3](https://www.mdpi.com/2076-3417/11/22/10827)]. 2. **Initial Model Creation**: - **Initial Velocity Model**: Building an initial velocity model from the collected seismic data using first arrival travel-times [[4](https://www.researchgate.net/publication/325060084_Near-surface_Seismic_Velocity_Model_Building_from_First_Arrival_Travel-times_-_A_Case_Study_from_an_Onshore_Niger_Delta_Field)]. - **Geological Constraints**: Incorporating geological information to constrain the initial model. 3. **Model Refinement**: - **Full Waveform Inversion (FWI)**: Using FWI techniques to refine the velocity model, enhancing the resolution and accuracy of subsurface features [[2](https://www.cgg.com/geoscience/subsurface-imaging/full-waveform-inversion)]. - **Iterative Updates**: Repeatedly updating the model with new data and refinements to improve accuracy [[1](https://wiki.seg.org/wiki/Near-Surface_Modeling_and_Imaging)]. 4. **Data Processing**: - **Static Corrections**: Applying corrections to account for near-surface velocity variations and ensure consistent seismic data [[4](https://www.researchgate.net/publication/325060084_Near-surface_Seismic_Velocity_Model_Building_from_First_Arrival_Travel-times_-_A_Case_Study_from_an_Onshore_Niger_Delta_Field)]. - **Noise Attenuation**: Reducing noise from the data to enhance signal quality. 5. **Validation and Finalization**: - **Model Validation**: Validating the near-surface model against known geological features and other geophysical data. - **Final Model Application**: Using the final near-surface model to process and interpret the deeper seismic data accurately [[1](https://wiki.seg.org/wiki/Near-Surface_Modeling_and_Imaging)]. This systematic approach ensures that the near-surface effects are accurately accounted for, leading to better imaging of deeper subsurface structures and more reliable geological interpretations.