靖边气田“硫水耦合”现象的成因与启示

靖边气田膏岩稳定发育，地层水和硫化氢分布局限，气田富硫区不受膏岩控制，而与富水区叠置耦合。通过模拟实验和地层埋藏演化史分析，从硫化氢生成条件及地层流体运动学角度探讨了这一现象的成因。结果表明，地层水对硫化氢生成的控制作用和储层强非均质性导致的气水分离不彻底是 “硫水耦合”的关键。该问题的研究说明：①靖边气田含硫天然气生成过程始终受地层水控制；②现今硫化氢分布是气水分离结果，并受储层非均质限制；③揭示地层水体分布的局限性可能是形成我国低含硫气田的一个重要机制。

Causation and Implication of the Coincidence of Formation Water and Hydrogen Sulphide in Jingbian Gas Field

       Gypsum rocks are stably developed and the distribution of formation water and hydrogen sulphide is limited in the Jingbian gas field. Sulphur\|rich areas are not controlled by the gypsum rocks and are associated with water\|rich areas. Through experiment and the analysis of tectonic evolvement, this paper discusses the causation of the coincidence of formation water and hydrogen sulphide. The phenomenon is caused by the control of formation water on the hydrogen sulphide formation and by the incomplete separation of water and gas due to strong heterogeneity of reservoirs. The study shows: (1) the generation of sulphur\|bearing gas is controlled by the formation water; (2) the present distribution of hydrogen sulphide is the result of the segregation of water and gas, and it is also influenced by the heterogeneity of reservoirs; (3) the limited distribution of formation water is an important mechanism for forming gas fields of low sulphur content in China.