The backwash imbibition may compromise the reservoir protection effects of WBM underbalanced drilling.However, research on this subject has seldom been done up till now.

• 这种自吸效应可能对砂岩气藏水基欠平衡钻井的储层保护效果产生影响，但目前与之有关的实验研究还很缺乏。