Due to the diversity and heterogeneity of shale composition, the surface of shale is negatively charged and contains clay minerals. When exposed to water, shale is prone to hydrolysis, which is not conducive to the stability of shale formation. Therefore, in this paper; we have optimized the formulation of the positive-gel drilling fluid that can effectively reduce the surface tension and increase the contact angle between the drilling fluid and the shale. To study the parameters of the optimized formula, the basic performance test, swellability test, and rolling recovery test of the water-based drilling fluid were carried out. The results show that both the organic positive gel MMH-1 and inorganic positive gel MMH-2 can effectively reduce the electrical properties of the shale surface. The drilling fluid containing a composite positive gel 0.6% MMH-1 + 1.5% MMH-2 can reduce the surface tension of the shale by 15.2% and increase the contact angle of the shale by 22.1%. The temperature resistance of the composite drilling fluid B is satisfactory, and the rolling recovery rate is as high as 98.4%, which can effectively enhance the stability of the shale formation.

由于页岩成分的多样性和非均质性，页岩表面带负电并含有粘土矿物。当暴露于水时，页岩易于水解，这不利于页岩形成的稳定性。因此，本文 我们优化了正凝胶钻井液配方，可以有效降低表面张力并增加钻井液与页岩之间的接触角。为了研究优化配方的参数，进行了水基钻井液的基本性能测试，溶胀性测试和滚动恢复测试。结果表明，有机正凝胶MMH-1和无机正凝胶MMH-2均可有效降低页岩表面的电学性质。含有复合正胶0的钻井液。6％MMH-1 + 1.5％MMH-2可使页岩的表面张力降低15.2％，并使页岩的接触角增加22.1％。复合钻井液B的耐热性令人满意，轧制回复率高达98.4％，可以有效提高页岩地层的稳定性。