下扬子地区望江坳陷页岩气地质调查皖望地4井钻井技术

Drilling technology of Well Wanwangdi-4 for shale gas geological surveyin the Wangjiang Depression of the Lower Yangtze Area

为查明下扬子地区望江坳陷白垩系-二叠系地层岩性和层序、验证地球物理信息、评价油气资源潜力,中国地质调查局部署了大口径页岩气地质调查井皖望地4井,完钻井深2503.9 m。针对钻遇地层多变、软硬互层、大段多层膏岩层等复杂情况,通过钻头适应性优化、钻具组合稳斜纠斜、稳定可靠的钻井液体系等钻探工艺技术的实施,实现防斜打直快速穿越,保证了岩心采取率,实现了钻井目的。该井钻井技术可为周边地区油气钻探提供有益经验。

In order to investigate the lithology and stratigraphy of the Cretaceous-Permian strata in the Wangjiang Depression of the Lower Yangtze Area,verify the geophysical information,and evaluate the petroleum potential,the Wanwangdi 4 well was deployed by the China Geological Survey,which is a large‑caliber shale gas geological survey well,and the total depth of which is 2503.9m.To deal with the complex drilling situation of variable formations,soft and hard interlayers,and large sections of multi‑layered mudstone layers,drilling technologies such as bit adaptability optimization,inclination correction and reliable drilling fluid system were implemented to achieve anti‑deviation and fast penetration,ensure core recovery rate,and achieve the drilling goals.The drilling technology used in this well can provide useful experience for oil and gas drilling in surrounding areas.