A. P. Annan, “Practical Processing of GPR Data,” Sensors and Software, Ontario, 1999. (http://www.ees.nmt.edu/outside/courses/Geop446/Docs/GPR_data_process.pdf)

As a starting point.

Static Correct (max phase) to set the surface to zero depth.

Energy decay gain to compensate for attenuation.

Background Removal to remove noise bands.

You can also finesse data using different 1D filters, 2 D filters, gain function and Migration tailored to you data set and what you are trying to achieve. Note every processing may add or subtract some spurious data. Be aware of the limitations and try to keep processing to a minimum to achieve you goal.

Recommended reading:

"Ground Penetrating Radar" David J. Daniels

"Ground Penetrating Radar: Theory and Apllication" Harry M Jol

"Tutorial 1 - Introduction to Ground Penetrating Radar" A.P.Annan GPR2000 International Conference

Utilizing Ground-Penetrating Radar (GPR) for geological layer picking involves several key processing steps:

1) Data Acquisition: Ensure suitable frequency and configuration, transmitting radar pulses into the ground and recording returned signals.

2) Time-Zero Correction: Align traces for synchronization, adjusting the starting time of the recorded signals.

3) Background Subtraction: Remove low-frequency noise and unwanted trends to highlight desired signals.

4) Gain Recovery: Apply correctional gains to compensate for signal attenuation with depth.

5) Filtering: Employ filters, such as band-pass, to suppress undesired frequencies and enhance signal quality.

6) Migration: Implement migration algorithms to locate reflectors in their accurate subsurface positions, providing a coherent image of the subsurface. These steps guide practitioners in achieving clear, interpretable GPR profiles for effective geological layer identification and analysis.

Thank you all for your valuable and very helpful answers. I will definitely follow the steps and go through recommendations