克依构造带气藏储层特征及伤害因素分析

克依构造带是塔里木盆地最大的储气构造。由于对储层特征及储层潜在伤害的因素认识不足,导致工艺措施不当对储层造成伤害,从而影响气井产能。通过岩心分析测试和室内试验评价,对克依构造带储层特征作了分析研究,并对储层潜在伤害因素进行了简要分析,提出了相应的储层保护措施。研究表明,克依构造带气藏储层属于碎屑岩、中—小孔—微孔、中—低渗、中—细短喉道,具有强层内和平面非均质性的气藏。对于不同区块、不同层位的储层应采取不同的储层保护措施。对于克拉苏区块巴什基奇克组应防止固相颗粒侵入、液相侵入和各种敏感性伤害;对于大北、吐北和吐孜区块的浅层气藏应注意各种敏感性伤害、水锁和固相颗粒及液相的侵入;对于依奇克里克构造带阳霞组和阿合组主要应防止储层的水锁伤害和自吸水,同时注意各种敏感性伤害,储层段如果发育各种成因的裂缝,在高比重泥浆条件下要防止压裂式井漏。

Analysis of Characteristics of Gas Reservoir and Damage Factors of Key Tectonic Zone

Keyi tectonic zone is the largest gas - producing structure in Tarim Basin. Because of the deficient knowledge of reservoir characteristics and the factors, which can result in formation damage, some technological measure damaged the reservoir, which affected the gas well production. According to laboratory core- analysis and in - house damage test of sensibility, the reservoir characteristics of Key tectonic zone and the factors which damaged the reservoir are studied, and latent damage factors of reservoir are briefly analyzed, and the relevant reservoir safeguards are proposed. Through investigation, the type of rock is debrital rock, and the types of reservoir spaces are medium - fine - micro porosity, and the reservoir has medium - low permeability and medium -fine throat. The reservoir is a gas reservoir with strong internal and planar heterogeneity. For different reservoir, different measures to safeguard reservoir should be carried out. For Bashijiqike in Kelasu tectonic zone, the invasion of solid particle, liquid and other sensibility damage should be avoided. For shallow gas reservoir in Dabei?Tubei and Tuzi area, we should take more attention to sensibility damage, block by water and invasion of solid particle and liquid. For Yangxia and Ahe of Yiqikelike tectonic zone, we should prevent block by water and spontaneous imbibitions, and at the same time, we should notice other sensibility damage. If there developed some crack, we should avoid fracturing circulation loss under the high proportion mud.