摘要：According to reservoir damage problems in Lower Paleozoic of Jingnan Block, the geological and physical characteristics of target reservoirs were analyzed. Then potential reservoir damage factors and damage mechanism were studied through comprehensive sensitivity experiments and water lock test. The results show that the target reservoir has strong water sensitivity damage, water-lock effect and pressure sensitivity damage. Based on fractured reservoir damage mechanism analysis, temporary blocking countermeasures were carried out. In addition, environmentally spherical particles and fibrous temporary plugging materials (QXZ and XWZ) were optimized and combined to achieve ideal temporary plugging effect. Considering complicated drilling case in target block, novel reservoir protection drilling fluid HPW was established. It exhibits good rheological properties, lubricating performance and filter loss properties. Furthermore, preferable inhibition and reservoir protection performance can be achieved. On this basis, the field trial results show that density, rheological properties, loss properties and lubricating performance of HPW have a greater improvement. And the drilling cycle and operation cost have been greatly shortened.
