| dc.description.abstract | To calculate the porosity-depth and permeability-depth relationship in TPCS-M1 borehole, we establish the stress-history dependent porosity/permeability model of rock cores based on rock sample porosity/permeability measurements. First, we categorize the sedimentary lithology of each rock samples into four types (sandstone, muddy sandstone, sandy mudstone and mudstone) according to their pore size distribution information. Second, we measure the porosity/permeability of sedimentary rock samples under various effective confining pressure to establish the stress-history dependent porosity/permeability model for four types of sedimentary rocks. Last, we calculate the porosity-depth and permeability-depth relationship in TPCS-M1 borehole based on these model. To check if the calculated porosity is reasonable or not, we compare the calculated result with porosity derived from log and porosity derived from image of thin section. We find using porosity measurement from lab and stress-history dependent porosity model can well calculate the porosity in sandstone layer, and also can estimate the trend of porosity changing in depth with lithology. On the other hand, we use the porosity derived from log and stress-history dependent porosity-permeability relationship for four types of sedimentary rocks to quickly estimated the permeability, comparing with the calculated permeability. The result shows that, the permeability estimated by the stress-history dependent porosity-permeability relationship is always close to the permeability calculated by experimental data and stress-history dependent permeability model in the same layer (same lithology type and depth), but totally different in different layer, it indicates the result of categorizing and building the strata’s lithology will significantly influence the permeability estimated result. Thus, if we want to estimate the permeability-depth relationship by these two methods, the most critical issue will be how to well categorize and build the strata’s lithology. | en_US |