阿姆河右岸复杂碳酸盐气藏上覆巨厚盐膏层优快钻井技术

QUICK AND EFFECTIVE DRILLING TECHNOLOGY OF COMPLEX CARBONATE GAS RESERVOIRS OVERLYING ULTRA-THICK SALT-GYPSUM FORMATION IN AMU DARYA RIGHT BANK

阿姆河右岸钻遇地层具有浅层高压次生气藏、高压盐水层、高压目的层、高产储层、巨厚盐膏层等"四高一厚"的特征,高压层及巨厚盐膏层安全快速钻进、缝洞型高压储层保护难度大,严重影响高效安全钻井。为了实现稀井高产、高效开发的目的,需要大规模实施大斜度井整体开发,由于目的层上覆巨厚盐膏层,导致造斜段增斜段均在盐膏层中,对井眼轨迹控制提出更高要求。针对上述钻井技术瓶颈及生产需求,开展了分段式地层压力预测、井身结构优化、井眼轨迹优化及钻井液体系优选等技术攻关与研究,形成了浅层次生高压气藏安全钻井、巨厚盐膏层大斜度井钻井、高压缝洞型气藏及上覆巨厚盐膏层钻井流体等特色技术,基本解决了长期困扰阿姆河右岸气田开发的钻井技术难题。

The Amu Darya River right bank is characterized by shallow secondary gas reservoirs with high pressures,high pressure brine layers,high pressure target layers,highly productive reservoirs and ultra-thick salt-gypsum layers,which bring challenges to the drilling operation of high pressure and ultra-thick salt-gypsum layers,protection of fractured high pressure reservoirs as well as the overall drilling safety and efficiency. In order to improve production of each well and overall development efficiency, the integrated development program of highly-deviated wells should be carried out by large scale. For the ultra-thick salt-gypsum layer above the target formation resulted in the kick-off section and buildup section in salt-gypsum formation,the higher requirements of borehole trajectory control were put forward. According to above problems,the sectional formation pressure prediction,casing program optimization,optimizing design of wellbore trajectory and optimization selection of drilling fluid etc. techniques were studied,some quick and effective drilling technologies suited for the shallow secondary high pressure gas reservoirs,highly-deviated well in ultra-thick saltgypsum layers and fractured reservoir with high pressure were formed. Field application results showed that the quick and effective drilling technologies could solve the drilling problems of gas field development in Amu Darya River right bank.