霍尔果斯背斜深井井身结构优化设计

Casing Program Optimization of Deep Well in Horgos Anticline

摘要:

霍尔果斯背斜受山前构造的影响，存在地质情况复杂、倾角大、多套压力体系并存以及泥岩含量高等问题，在钻进过程中复杂事故频发，严重制约了该地区油气勘探开发的进程。通过对完钻井的测井资料、地破实验数据、钻井复杂等资料的分析，确定必封点位置，形成适合霍尔果斯背斜深探井的四开井身结构，并针对安集海河组复杂事故率高的情况，采用高密度油基钻井液抑制泥岩水化，从而实现安全钻进。优化后的井身结构在霍尔果斯背斜深探井H11井进行了应用，首次实现了在安集海河组、紫泥泉子组两套压力系统下进行套打，历时5.5 d钻穿“死亡之海”安集海河组，未出现井漏现象，取得了良好的应用效果。优化后的井身结构在H11井的成功应用，不仅为该地区深探井的井身结构设计提供依据，也为该地区后续常规井的四开转三开井身结构提供了指导。

Abstract:

Affected by tectonic, there are problems of complex geological conditions, large inclination, multiple pressure systems coexisting and high mudstone content in Horgos anticline, frequent complicated accidents seriously restricted the oil and gas exploitation and development process in this area. Based on the analysis on logging data, ground breaking experimental data and complicated well drilling and completion situation, the setting position was determined for 4interval casing program of deep exploration well in Horgos anticline, and aiming at high complicated accident rate in Anjihaihe formation, by using high density oil-based drilling fluid, mudstone hydration was inhibited to realize safe drilling. The optimized casing program was applied in deep exploration well H11 in Horgos anticline, drilling was carried out under the pressure of Anjihaihe and Ziniquanzi formations for the first time, it took 5.5 days to penetrate Anjihaihe formation without well leakage. This successful application not only provides the basis for the design of the casing program of the deep exploratory well in the area, but also provides guidance for subsequent conventional casing program with 4 sections changed to be 3 sections.