The unconsolidated sandstone reservoirs in the WC oilfield in the South China Sea is characterized by severe sand production,strong reservoir heterogeneity and staggered distribution of sandstone-mudstone inter-beds.However,traditional sand control methods are less applicable to such reservoirs,resulting in severe screen blockage and continuous decline in productivity,which seriously affects its normal development.In order to under-stand the mechanism by which sandstone-mudstone interbed blocks the sand control screen and select the sand con-trol method suitable for this type of reservoirs,a rotatable sand control physical simulation test device was devel-oped according to the analogy simulation principle.Then,using the test device,and considering the interbed ratio of sandstone-mudstone interbedded reservoir and the wellbore inclination depending on field conditions,the influ-ences of different factors on sand control methods were evaluated.The results show that the interbed ratio and well-bore inclination have significant impacts on the selection of sand control methods.When the interbed ratio is less than 0.4,high quality screen is preferred for sand control;otherwise,gravel pack sand control is applied.When the wellbore inclination is less than 45°,the interbed ratio has a relatively small impact on the gravel pack and blockage degree of sand control screen.When the wellbore inclination exceeds 45°,the impact of the wellbore in-clination on the blockage degree of sand control screen cannot be ignored.The study results have important guiding significance for optimization of sand control in sandstone-mudstone interbedded reservoirs.
关键词
防砂/砂泥岩互层/互层比/井斜角/筛管防砂/物理模拟
Key words
sand control/sandstone-mudstone interbed/interbed ratio/wellbore inclination/sand control of screen/physical simulation
维普
万方数据