对五八区佳木河组沉积特征和储层特征的整体认识

Abstract

准噶尔盆地西北缘五八区佳木河组地层厚度较大，火山岩和碎屑岩共存。研究区发育有5个相，分别是冲积扇相、扇三角洲相、喷溢相、爆发相和再搬运火山碎屑岩相。佳木河组一段发育火山岩相和扇三角洲相以及冲积扇的扇中亚相，而火山岩分布范围广，且多岩断层分布。佳木河组一段物性较好，I、II类储层较多，且多发育在火山相中，而碎屑岩多为III类储层。佳木河组二段和三段以扇三角洲为主，三段的火山岩相比二段发育。佳木河组二段和三段以III类储层为主，同样发育有I、II类储层。佳木河组多为好储层，且试油量较高，因此佳木河组可作为油气勘探开发的重点层位。佳木河组的I、II类储层主要发育在喷溢相的下部亚相和爆发相的热碎屑流亚相，火山岩储层值得重视，重点对裂缝和溶蚀带进行预测。 The stratum of Jiamuhe Formation in northwestern margin of the Junggar basin is very thick, which consists of volcano rock and clastic rock. There are 5 facies in the study area including alluvial fan facies, fan delta facies, effusive facies, eruption facies and retransported volcano clastic facies. The first member of Jiamuhe Formation, in which volcanic rock widely distributes along the fault, develops volcano facies, fan delta facies and middle alluvial fan sub-facies. The physical property of the first member of Jiamuhe Formation is better, which develops I or II class reservoir in the volcano clastic rock facies while the class III reservoir mostly develops in the clastic rocks. The fan delta facies are widely developed in the second member and third member of Jiamuhe Formation, and the volcanics in the third member are much more than the second member. The mainly reservoir type in the second member and third member of Jiamuhe Formation is III class reservoir, while I, II class reservoirs are also developed in it. Jiamuhe Formation is a good reservoir, the oil content is high, and soit can be taken as a key position for oil & gas exploration and development. The I class and II class reservoirs in the Jiamuhe Formation are mainly developed in the lower subfacies of effusive facies and hot detrital flow subfacies of outbreak facies. Volcanic rock reservoir is worth paying attention to and focusing on the prediction of fractures and dissolution zone.