论文部分内容阅读
准噶尔盆地侏罗系Ⅲ层序底界面结构主要有发育底砾岩的不整合型、发育风化壳的假整合型和具明显沉积型式变化的整合型等 3类。在侏罗系Ⅲ层序底界面上、下延 4 0ms的波形地震相中 ,1～ 2类高频波形对应砂泥岩互层沉积 ;5～ 6类低频波形对应大套砂岩沉积 ;3～ 4类波形介于二者之间。地震波的振幅与界面上的岩石组合有关 ,中强振幅对应于砂、泥岩组合以及砾岩、粉砂岩组合 ,弱振幅对应于大套砂岩组合 ,中振幅介于二者之间。另外 ,低频波和中强振幅与地震前积反射有较好的对应关系。通过波形地震相、振幅以及反射结构的综合分析 ,认为玛湖西北斜坡和腹部的石南 -莫北地区有大面积的砂体分布 ,其中 ,车 -拐水下扇、玛湖辫状三角洲、中拐曲流河三角洲及石南 -夏盐曲流河三角洲等砂体发育区是有利的非构造圈闭发育区 ,具有良好的勘探前景
There are three types of interfacial structures at the bottom of the Jurassic Ⅲ sequence in the Junggar Basin: unconformity of the basement conglomerate, unconformity of the developed weathering crust, and integration of obvious sedimentary changes. At the bottom of the Jurassic Ⅲ sequence interface, 1 to 2 types of high-frequency waveforms correspond to sand-shale interbedded sediments in the waveform seismic facies extended for 4 ms; 5 to 6 low-frequency waveforms correspond to large sets of sandstone sediments; 3 to 4 The class waveform is between the two. The amplitude of the seismic wave is related to the rock assemblage at the interface. The moderate amplitude corresponds to the combination of sand and mudstone, conglomerate and siltstone, and the weak amplitude corresponds to the large sandstone assemblage. The amplitude of the medium amplitude is in between. In addition, there is a good correspondence between low-frequency waves and moderate-strong amplitudes and pre-seismic product reflections. Based on the comprehensive analysis of seismic facies, amplitudes and reflection structures, it is concluded that there is a large area of sand body distribution in the Shensan-Mobei area on the northwestern slope of Mahu and in the abdomen. Among them, the car-braided delta, Sand dune development zones, such as Zhongli meandering stream delta and Shek Nga - Xiayan meandering delta, are favorable non-structural trap areas with good exploration prospects