中伊朗盆地卡山地区Aran构造带油气成藏

Hydrocarbon reservoirs formation of Aran structural belt in Kashan area,central Iran Basin

中伊朗盆地卡山地区Aran构造带已钻探井3口,其中Arn-1井获工业性油气流,随后勘探失利。为了揭示该构造带在Arn-1井和Arn-2井地区的构造差异,分析勘探失利的原因,通过对Aran构造带过井地震剖面的构造演化分析,明确了构造运动与圈闭形成和烃源岩生烃时间与空间的匹配关系;并根据流体地化性质探讨了Aran构造带油气成藏特征。研究结果表明,Arn-1井和Arn-2井地区都经历了相同的构造运动,但库姆组沉积末期的构造运动使Arn-2井地区遭受抬升剥蚀;Arn-2井库姆组中所充注的流体,均来自于寄主围岩以外的库姆组自身,未捕获到侏罗系油气;Aran构造带主要形成了库姆组"自生自储"油气藏。

Three wells have been drilled in the Aran structural belt of Kashan area in the central Iranian Basin. Well Arn-1 obtained commercial petroleum. However,the rest of wells were dry. Structural evolution of seismic section joining wells of Aran structural bell was analyzed to reveal the structural difference between well Arn -1 and Am-2 and the reason of exploration loss. The time-space matching relation among tectonic movement, formation of traps, and hydrocarbon generation was determined. And the characteristics of petroleum accumulation were researched depending on the geochemical data in Aran structural belt. The results show: ( 1 ) the areas of well Arn-1 and Arn-2 experienced the same tectonic movement,but well Arn-2 area was uplifted and eroded by the tectonic movement at the end of Qom formation sedimentation; (2) the fluid in Qom formation of well Arn-2 area was from the Qom formation itself outside the fluid host rocks, and did not capture oil-and-gas from Jurassic rocks; (3) the source rock and reservoir rock in Qom formation were in the same bed. which formed petroleum pools in Aran structural belt.