论文部分内容阅读
首次将沉积波动过程分析这一新技术方法应用于米仓山前陆冲断带的构造沉积演化和油气成藏条件研究中,通过对研究区内典型井和露头剖面的波动特征分析,得出米仓山前陆冲断带存在有2个一级沉积波动周期(220Ma),其分别与加里东-海西和印支-燕山-喜马拉雅两个构造旋回相对应;4个二级沉积波动周期(100Ma),其与研究区两个沉积高峰期和两个剥蚀高峰期相对应;12个三级沉积波动(35Ma)和21个四级沉积波动周期(20Ma),它们与研究区不同时期沉积—剥蚀过程相对应.研究还发现35Ma周期和20Ma周期的波动曲线特征与生油层、储集层和盖层发育规律具有成因联系:生油层一般发育在“波峰”与“波谷”之间的转折部位,或是不同波动周期的波动曲线转折部位的叠加,呈现“X”型;储集层多发育在波动特征曲线的“波峰”部位;盖层多发育在波动特征曲线位于沉积-剥蚀基准线右侧的“波谷”部位.因此,应用沉积波动过程分析这一新技术方法,即可以从成因角度重新认识研究区构造沉积演化过程,同时可以预测生储盖层的发育规律,对成藏条件研究具有重要的意义.
For the first time, the new method of sedimentary fluctuation analysis was applied to tectonic evolution and hydrocarbon accumulation in the Micangshan foreland thrust belt. By analyzing the fluctuation characteristics of typical wells and outcrop sections in the study area, There are two first-order sedimentary cycles (220Ma) in the Micangshan foreland thrust belt corresponding to two tectonic cycles of the Caledonian-Hercynian and Indo-Yanshan-Himalayas respectively. Four second-order sedimentary cycles (100Ma) corresponding to two depositional peaks and two erosion peaks in the study area. Twelve tertiary sedimentation fluctuations (35Ma) and 21 fourth-order sedimentation fluctuation cycles (20Ma), which were deposited in different periods of the study area - denudation process.The study also found that the characteristics of fluctuation curves in 35Ma cycle and 20Ma cycle have a genetic relationship with the genesis of oil and gas reservoir and caprock: the oil layer generally develops in “crest” and “trough” , Or “” pattern of the transitional parts of the fluctuation curve with different fluctuation periods. The reservoirs mostly develop in the “ridges” of the fluctuation curve; The characteristic curve is to the right of the sedimentation-erosion baseline Therefore, applying the new technique and method of sedimentary fluctuation analysis can re-understand the tectonic evolution and evolution of the study area from the genetic point of view, meanwhile, it can predict the developmental rules of the reservoirs and reservoirs, It is of great significance.