【摘要】 疏松砂岩储层是一种重要的储层类型,此类储层具有未固结沉积特征明显,胶结物含量少,胶结程度低,砂岩呈疏松状的特点,研究难度相当大。国内外很多学者采用AVO和衰减梯度等烃类检测方法对该类型储层进行预测,结果存在很大的不确定性。以柴达木盆地三湖地区的疏松砂岩为例,比较了各种谱分解方法的分辨能力,采用高精度的指数匹配追踪谱分解技术,利用含气地层对高频能量的吸收,含气储层的主频向低频移动的特点进行气藏检测。结果表明,该方法能够准确刻画地震信号在时频空间分布特征,能够有效检测三湖地区气藏位置,提供可钻探圈闭,具有很强的实际生产价值。更多还原

【Abstract】 Unconsolidated sandstone reservoir was an important reservoir characterized by unconsolidated sedimentary,less cement,and low cementation,therefore it was very difficult for studying the reservoir.Some geophysicists both at home and abroad tried to predict this type of reservoir by using hydrocarbon detection methods such as AVO,and attenuation gradient,yet the result was highly uncertain.By tacking unconsolidated sandstone in Sanhu Region of Qaidam Basin for example,the resolution of several spectrum decomposition methods was compared and high precision index matching tracing spectral decomposition was used for hydrocarbon detection,the gas-bearing reservoirs were detected through the absorption of high frequency energy in gas-bearing formation and the dominant frequency shifting toward the low band.The result demonstrates that this method can accurately map seismic signal in time-frequency domain,and effectively predict gas reservoir location in Sanhu Region,which is valuable for trap positioning and drilling.更多还原