Author(s): PA Enikanselu
A total of twenty-nine (29) reverse-shooting seismic refraction lines and uphole survey data from one well have been analyzed, aimed at unraveling the weathered layer geophysical characteristics in “Mono” field, onshore NW Niger delta, Nigeria. The time-intercept technique of seismic refraction interpretation was employed while the conventional method of well shooting analysis used in the uphole well surveys. Results of data interpretation revealed that the thickness of the weathered layer is fairly uniformly thin in the area, ranging from 3.50m around the western and eastern flanks to 5.30m at the north central location with a regional average of 4.4 m. The average weathered layer compressional wave velocity was about 525 m/s; ranging from 300 m/s to 750 m/s around the north west and south eastern flanks and central portion of the study area respectively. The underlying consolidated layer has an average velocity of about 1800 m/s adjudged sufficiently competent to withstand engineering structures.