Abstract:

Aim at the situations of structure formation characteristic and the damage tended fracture reservoir in the Shizigou ofChaidamu, also high formation water salinity that easy to bring sedimentation from the physical chemistry reaction with the external fluid, which blocking the oil and gas passage, a drilling fluid with high formationwater salinity has been usedwhich is proximity to the formationwater characteristic and reduce the damage of the formation. According to the mechanics research results of damage reservoir of Shizigou E13, we design the shielding and temporary block technology and select the formulation of drilling fluid to protect formation. By field application in the 25-1 the Tianshi ofShizigou, results show that the shielding and blocking up technologymay not onlymeet demand in the horizontalwell construction but also has good effects on reservoir protection.

Key words: sdrilling fluid, formation damage, reservoir protection, the shielding and temporary block technology, inverted drain