致密碎屑岩气藏地震频变特征主控因素定量分析

利用地震频变属性进行深层致密碎屑岩气藏含气性检测是重要攻关方向，但是影响地震频变特征的的因素有很多，有必要对控制因素进行定量分析。本文以东营凹陷民丰地区实际地质情况为约束，利用地震正演模拟技术，对影响致密碎屑岩气藏频变特征的埋深、岩性、储层厚度等因素进行了定量分析，并且利用实际地震资料对地震频率变化率和日产气量进行了对比分析。分析表明: 对于埋深较大的深层致密碎屑岩气藏，埋深、地层韵律性、岩性等因素对地震频变特征影响较小，储层厚度和含气性是影响地震频变特征的主要因素，地震频率变化率与日产气量具有较好的相关性。针对某一具体目的层，储层厚度在一定范围内变化时，可以使用地震频变特征预测储层含气性。

Main Controlling Factors Quantitative Analysis of Seismic Frequency-varying Characteristics of Tight Clastic Gas Reservoirs

It is an important research area to detect deep tight clastic gas reservoirs using seismic frequency-varying attributes. But there are many factors affecting the seismic frequency-varying characteristics. It is necessary to conduct quantitative analysis of control factors. This paper is based on the actual geological conditions in Minfeng area of Dongying depression. The seismic forward modeling technique was used and it was carried out that quantitative analysis of buried depth, lithology, reservoir thickness and other factors affecting frequency-varying characteristics of tight clastic gas reservoirs. A comparative analysis of seismic frequency-variation-rate and daily gas production is made by using actual seismic data. The analysis shows that the reservoir thickness and gas-bearing property are the main factors affecting the characteristics of seismic frequency variation under a certain buried depth. There is a good correlation between seismic frequency-variation-rate and daily gas production. For a specific target layer, its thickness varies within a certain range, and the reservoir gas-bearing property can be predicted by using seismic frequency-varying characteristics.