@article{Avirut Puttiwongrak_Pham Huy Giao_Sakanann Vann_2020, title={AN EASILY USED MATHEMATICAL MODEL OF POROSITY CHANGE WITH DEPTH AND GEOLOGIC TIME IN DEEP SHALE COMPACTION}, volume={19}, url={https://geomatejournal.com/geomate/article/view/1781}, abstractNote={<p>Shale compaction behavior is complex and differs from sandstone. The compaction trend shows<br>marked changes in the physical properties with increasing depth. Therefore, the porosity-depth curve in the<br>shallow section is not well established. Several authors published porosity-depth curves in which vary<br>considerably, particularly in the shallow part of the compaction trend. Deep shale compaction curves show<br>deviations in the trend of porosity decreasing with depth, especially at shallow depths where mechanical<br>compaction is dominant and this suggests that mechanical compaction is not the only factor causing porosity<br>change and that geological time is another important factor to be considered. In this study twenty-two sets of<br>published data on deep shale compaction up to a depth of 5 km from various sedimentary basins around the<br>world were synthesized and analyzed to depict the effect of geological age on deep shale compaction curves.<br>A time-dependent solution of the compaction equation with porosity as the variable was revisited, based on<br>which and in combination with multivariate curve-fitting of the collected compaction data, a new and easilyused mathematical model of porosity-depth-geological time was derived. Finally, research results substantiate<br>that a burial depth (overburden pressure) cannot be considered only for studying mechanical compaction of<br>shales, the geological age (an effect of time) is necessary to take into account.<br><br></p>}, number={73}, journal={GEOMATE Journal}, author={Avirut Puttiwongrak and Pham Huy Giao and Sakanann Vann}, year={2020}, month={Sep.}, pages={108–115} }