In this paper we addresse the changes in physical properties of the Eocene and Paleocene shale from the Atlantic Basin, as a function of burial diagenesis. We also showed the influence of using correct Biot’s coefficient (β) on the estimation of vertical effective stress. We correlated our porosity and P-wave velocity data with the calculated effective stresses to show how different calculated vertical effective stress influences shale compaction trends. This may provide a basis to understand how physical properties vary with effective stress and shale mineralogy. Our results may be relevant for drilling, basin analysis modeling, seismic interpretation and hydrocarbon exploration.