Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption
Fractal dimension (D) is a critical parameter to estimate the heterogeneity of complex pore structure in shale gas reservoirs. To quantify the fractal dimension of various pore types and evaluate their implications on shale effective porosity and gas storage capacity in potential, we performed fract...
| Main Authors: | , |
|---|---|
| Format: | Journal Article |
| Language: | English |
| Published: |
ELSEVIER SCIENCE BV
2019
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/89569 |
| _version_ | 1848765247981092864 |
|---|---|
| author | Yuan, Yujie Rezaee, Reza |
| author_facet | Yuan, Yujie Rezaee, Reza |
| author_sort | Yuan, Yujie |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Fractal dimension (D) is a critical parameter to estimate the heterogeneity of complex pore structure in shale gas reservoirs. To quantify the fractal dimension of various pore types and evaluate their implications on shale effective porosity and gas storage capacity in potential, we performed fractal analysis based on experimental results of low-field nuclear magnetic resonance (LF-NMR) and low-pressure N2 gas adsorption (LP-N2-GA) in Permian Carynginia shales. By comparing the calculated fractal dimensions based on the two approaches, we analyzed the ‘surface fractal dimension’ for ineffective pores occupied by clay bound water (CBW) and the ‘volume fractal dimension’ for effective pores (Deff) holding removable fluids for the first time in shales. The NMR-based CBW pore fractal dimension (Dcbw) is linear positively correlated with the fractal dimension of micropore surface (D1) (R2 = 0.91) and the volume of CBW (R2 = 0.58), while negatively correlated with effective porosity (R2 = 0.58). The NMR-based effective pore fractal dimension (Deff) is linear positively correlated with the fractal dimension of meso/macropore volume (D2) (R2 = 0.82) and presents a good positive correlation with gas storage capacity (R2 = 0.80). The results indicate that CBW largely complicates the fractal geometry of nanoscaled pore network and potentially resist effective fluid flows in shales. The pore surface of higher heterogeneity (higher D1) associates with larger surficial CBW retention and would further block the effective pore space for fluid transport. The meso/macropore volumes of higher complexity (higher D2) is intimate with the larger heterogeneity in effective pores for the higher potential of hydrocarbon storage capacity in gas shales. |
| first_indexed | 2025-11-14T11:32:14Z |
| format | Journal Article |
| id | curtin-20.500.11937-89569 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:32:14Z |
| publishDate | 2019 |
| publisher | ELSEVIER SCIENCE BV |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-895692022-11-14T05:10:59Z Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption Yuan, Yujie Rezaee, Reza Science & Technology Technology Energy & Fuels Engineering, Petroleum Engineering Shale NMR Low-pressure gas adsorption Fractal dimension Clay-bound water Gas storage capacity MISSISSIPPIAN BARNETT SHALE FORT-WORTH BASIN SURFACE-AREA POROSITY DIMENSION MODEL POROSIMETRY SYSTEMS QUANTIFICATION LITHOFACIES Fractal dimension (D) is a critical parameter to estimate the heterogeneity of complex pore structure in shale gas reservoirs. To quantify the fractal dimension of various pore types and evaluate their implications on shale effective porosity and gas storage capacity in potential, we performed fractal analysis based on experimental results of low-field nuclear magnetic resonance (LF-NMR) and low-pressure N2 gas adsorption (LP-N2-GA) in Permian Carynginia shales. By comparing the calculated fractal dimensions based on the two approaches, we analyzed the ‘surface fractal dimension’ for ineffective pores occupied by clay bound water (CBW) and the ‘volume fractal dimension’ for effective pores (Deff) holding removable fluids for the first time in shales. The NMR-based CBW pore fractal dimension (Dcbw) is linear positively correlated with the fractal dimension of micropore surface (D1) (R2 = 0.91) and the volume of CBW (R2 = 0.58), while negatively correlated with effective porosity (R2 = 0.58). The NMR-based effective pore fractal dimension (Deff) is linear positively correlated with the fractal dimension of meso/macropore volume (D2) (R2 = 0.82) and presents a good positive correlation with gas storage capacity (R2 = 0.80). The results indicate that CBW largely complicates the fractal geometry of nanoscaled pore network and potentially resist effective fluid flows in shales. The pore surface of higher heterogeneity (higher D1) associates with larger surficial CBW retention and would further block the effective pore space for fluid transport. The meso/macropore volumes of higher complexity (higher D2) is intimate with the larger heterogeneity in effective pores for the higher potential of hydrocarbon storage capacity in gas shales. 2019 Journal Article http://hdl.handle.net/20.500.11937/89569 10.1016/j.petrol.2019.02.082 English ELSEVIER SCIENCE BV restricted |
| spellingShingle | Science & Technology Technology Energy & Fuels Engineering, Petroleum Engineering Shale NMR Low-pressure gas adsorption Fractal dimension Clay-bound water Gas storage capacity MISSISSIPPIAN BARNETT SHALE FORT-WORTH BASIN SURFACE-AREA POROSITY DIMENSION MODEL POROSIMETRY SYSTEMS QUANTIFICATION LITHOFACIES Yuan, Yujie Rezaee, Reza Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption |
| title | Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption |
| title_full | Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption |
| title_fullStr | Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption |
| title_full_unstemmed | Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption |
| title_short | Fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on NMR and N2 gas adsorption |
| title_sort | fractal analysis of the pore structure for clay bound water and potential gas storage in shales based on nmr and n2 gas adsorption |
| topic | Science & Technology Technology Energy & Fuels Engineering, Petroleum Engineering Shale NMR Low-pressure gas adsorption Fractal dimension Clay-bound water Gas storage capacity MISSISSIPPIAN BARNETT SHALE FORT-WORTH BASIN SURFACE-AREA POROSITY DIMENSION MODEL POROSIMETRY SYSTEMS QUANTIFICATION LITHOFACIES |
| url | http://hdl.handle.net/20.500.11937/89569 |