In order to analyze the factors influencing sandstone mechanical compaction and its physical property evolution during compaction processes, simulation exper- iments on sandstone mechanical compaction were carried out...In order to analyze the factors influencing sandstone mechanical compaction and its physical property evolution during compaction processes, simulation exper- iments on sandstone mechanical compaction were carried out with a self-designed diagenetic simulation system. The experimental materials were modem sediments from dif- ferent sources, and the experiments were conducted under high temperature and high pressure. Results of the exper- iments show a binary function relation between primary porosity and mean size as well as sorting. With increasing overburden pressure during mechanical compaction, the evolution of porosity and permeability can be divided into rapid compaction at an early stage and slow compaction at a late stage, and the dividing pressure value of the two stages is about 12 MPa and the corresponding depth is about 600 m. In the slow compaction stage, there is a good exponential relationship between porosity and overburden pressure, while a good power function relationship exists between permeability and overburden pressure. There is also a good exponential relationship between porosity and permeability. The influence of particle size on sandstone mechanical compaction is mainly reflected in the slowcompaction stage, and the influence of sorting is mainly reflected in the rapid compaction stage. Abnormally high pressure effectively inhibits sandstone mechanical com- paction, and its control on sandstone mechanical com- paction is stronger than that of particle size and sorting. The influence of burial time on sandstone mechanical compaction is mainly in the slow compaction stage, and the porosity reduction caused by compaction is mainly con- trolled by average particle size.展开更多
Diagenesis of clastic rock and hydrocarbon generating capacity are closely related with diagenetic stages.Based on diagenetic evolution,reservoir diagenetic stages prediction method is proposed through making a contra...Diagenesis of clastic rock and hydrocarbon generating capacity are closely related with diagenetic stages.Based on diagenetic evolution,reservoir diagenetic stages prediction method is proposed through making a contrastive study of simulation results and test results using core measurement data.The essence of this method is illustrated and its effectiveness is demonstrated using Ed2 clastic sandstones in the west of Bozhong sag,Bohai Bay Basin,China.Measurement of paleo temperature(T),vitrinite reflectivity(Ro%)and the proportion of smectite in illite/smectite interstratified minerals(I/S-S%)indicate that there are there types of diagenetic stages in the study area,including early diagenetic stage B,middle diagenetic stage A1 and middle diagenetic stage A2.When only considering T index for diagenetic stages prediction,the simulation results are more conservative than measured data with some situations,and the simulation result using Ro%for diagenetic prediction is less than measured data in some wells.When I/S-S%is used,the two situations above both exist.Because depth,temperature,time duration,pressure and some chemical variables can change synchronously or asynchronously,it is difficult to attribute with certainty the parameters that affect the apparent diagenetic stages evolution series.Diagenetic stage variations can be significantly different in different parts of one sedimentary basin.A synthetic indexes method considering T,Ro%,I/S-S%to predict its distribution,and the simulation result has proved that the reliability of the model has greatly improved.展开更多
基金co-funded by the National Natural Science Foundation of China (Grant No.U1262203)the National Science and Technology Special Grant (Grant No.2011ZX05009003)+1 种基金the Fundamental Research Funds for the Central Universities (Grant No.14CX06013A)the Chinese Scholarship Council (No.201406450019)
文摘In order to analyze the factors influencing sandstone mechanical compaction and its physical property evolution during compaction processes, simulation exper- iments on sandstone mechanical compaction were carried out with a self-designed diagenetic simulation system. The experimental materials were modem sediments from dif- ferent sources, and the experiments were conducted under high temperature and high pressure. Results of the exper- iments show a binary function relation between primary porosity and mean size as well as sorting. With increasing overburden pressure during mechanical compaction, the evolution of porosity and permeability can be divided into rapid compaction at an early stage and slow compaction at a late stage, and the dividing pressure value of the two stages is about 12 MPa and the corresponding depth is about 600 m. In the slow compaction stage, there is a good exponential relationship between porosity and overburden pressure, while a good power function relationship exists between permeability and overburden pressure. There is also a good exponential relationship between porosity and permeability. The influence of particle size on sandstone mechanical compaction is mainly reflected in the slowcompaction stage, and the influence of sorting is mainly reflected in the rapid compaction stage. Abnormally high pressure effectively inhibits sandstone mechanical com- paction, and its control on sandstone mechanical com- paction is stronger than that of particle size and sorting. The influence of burial time on sandstone mechanical compaction is mainly in the slow compaction stage, and the porosity reduction caused by compaction is mainly con- trolled by average particle size.
基金This research work was funded by Major Projects of National Science and Technology“Large Oil and Gas Fields and CBM Development”(Grant No.2016ZX05027-02-007)Major Projects of National Science and Technology“Large Oil and Gas Fields and CBM Development”(Grant No.2016ZX05024-003-004)the National Natural Science Foundation of China(Grant No.41672119).
文摘Diagenesis of clastic rock and hydrocarbon generating capacity are closely related with diagenetic stages.Based on diagenetic evolution,reservoir diagenetic stages prediction method is proposed through making a contrastive study of simulation results and test results using core measurement data.The essence of this method is illustrated and its effectiveness is demonstrated using Ed2 clastic sandstones in the west of Bozhong sag,Bohai Bay Basin,China.Measurement of paleo temperature(T),vitrinite reflectivity(Ro%)and the proportion of smectite in illite/smectite interstratified minerals(I/S-S%)indicate that there are there types of diagenetic stages in the study area,including early diagenetic stage B,middle diagenetic stage A1 and middle diagenetic stage A2.When only considering T index for diagenetic stages prediction,the simulation results are more conservative than measured data with some situations,and the simulation result using Ro%for diagenetic prediction is less than measured data in some wells.When I/S-S%is used,the two situations above both exist.Because depth,temperature,time duration,pressure and some chemical variables can change synchronously or asynchronously,it is difficult to attribute with certainty the parameters that affect the apparent diagenetic stages evolution series.Diagenetic stage variations can be significantly different in different parts of one sedimentary basin.A synthetic indexes method considering T,Ro%,I/S-S%to predict its distribution,and the simulation result has proved that the reliability of the model has greatly improved.
