Automated near surface analysis by surface-consistent refraction methods

A data processing system forming measures of near surface corrections of seismic survey data in the form of a set of seismic survey traces obtained from records of seismic energy travel from seismic sources to an array of seismic detector geophones during a seismic survey, comprising:

• a memory storing computer operable instructions causing the data processing system to form the measures of near surface corrections of the seismic survey data;
• a processor performing under control of the computer operable instructions stored in the memory steps of:
• (a) assembling in the computer a seismic trace first break dataset detected by the array of detector geophones during the seismic survey as a result of first arrival times at the detector geophones of seismic energy from the sources;
• (b) sorting the arrival times of the seismic trace first break dataset into offset bins of a travel time attribute cube according to common midpoints for refracted seismic wave travel between the seismic sources and individual ones of the detector geophones of the array, the common midpoints being organized into dimensional offsets of the detector geophones of the array;
• (c) removing anomalous arrival times from the sorted arrival times in the offset bins to form a refined first break dataset;
• (d) forming common midpoint velocity functions for the traces of the offset bins based on the refined first break dataset;
• (e) forming measures of field static corrections for traces of the offset bins based on the common midpoint velocity functions;
• (f) applying the measures of field statics corrections to the set of seismic survey traces to form a set of field statics corrected seismic traces;
• (g) forming measures of refraction residual statics corrections for the set of field statics corrected seismic traces;
• and
• (h) applying the measures of refraction residual statics corrections to the traces of set of field statics corrected seismic traces to form near surface corrected seismic traces;
• and
• a memory receiving for storage the near surface corrected seismic traces.

A data storage device having stored in a non-transitory computer readable medium computer operable instructions for causing a data processing system comprising a memory and a processor to form measures of near surface corrections of seismic survey data in the form of a set of seismic survey traces obtained from records of seismic energy travel from seismic sources to an array of seismic detector geophones during a seismic survey, the instructions stored in the data storage device causing the data processing system to perform the following steps:

• storing in the memory computer operable instructions causing the data processing system to form the measures of near surface corrections of the seismic survey data;
• performing in the processor, under control of the stored computer operable instructions, steps to form measures of near surface corrections of seismic survey data comprising:
• (a) assembling in the computer a seismic trace first break dataset detected by the array of detector geophones during the seismic survey as a result of first arrival times at the detector geophones of seismic energy from the sources;
• (b) sorting the arrival times of the seismic trace first break dataset into offset bins of a travel time attribute cube according to common midpoints for refracted seismic wave travel between the seismic sources and individual ones of the detector geophones of the array, the common midpoints being organized into dimensional offsets of the detector geophones of the array;
• (c) removing anomalous arrival times from the sorted arrival times in the offset bins to form refined a first break dataset;
• (d) forming common midpoint velocity functions for the traces of the offset bins based on the refined first break dataset;
• (e) forming measures of field static corrections for traces of the offset bins based on the common midpoint velocity functions;
• (f) applying the measures of field statics corrections to the set of seismic survey traces to form a set of field statics corrected seismic traces;
• (g) forming measures of refraction residual statics corrections for the set of field statics corrected seismic traces;
• and
• (h) applying the measures of refraction residual statics corrections to the traces of set of field statics corrected seismic traces to form near surface corrected seismic traces.