频率衰减属性在深层碳酸盐岩油气勘探中的应用

Application of frequency attenuation attributes to oil and gas exploration in deep carbonate rocks

针对BL地区长兴组地层碳酸盐岩礁滩相岩性油气藏具有埋藏深、油气分布不均匀的特征,提出了应用频率衰减梯度属性和低频伴影现象相结合进行油气检测的思路。首先介绍了频率衰减梯度和低频伴影现象的方法原理;其次结合研究区长兴组地层的储层物性参数建立地质模型,运用黏滞弥散型波动方程模拟和分析了该类储层的地震响应特征,模型分析表明利用频率衰减梯度属性和低频伴影现象识别此类储层的含气性是可行的。实际资料的应用证实频率衰减梯度属性和低频伴影现象对该类储层都有较好的指示,其预测结果能够相互验证,提高了储层预测及流体检测的准确性,为BL地区长兴组地层碳酸盐岩礁滩相岩性油气藏及类似油气藏的油气识别及流体检测提供了思路。

According to deep burial depth,uneven oil and gas distribution of carbonate reef flat lithologic reservoir of Changxing Formation in BL area,this paper put forward a train of thought for hydrocarbon detection which combined frequency attenuation attributes and low frequency ad joint-shadow phenomenon.This paper first introduced the principle of frequency attenuation attributes and low frequency ad joint-shadow phenomenon;secondly established geological model combined with the reservoir physical parameters of Changxing Formation in BL area,and simulated and analyzed the seismic response characteristics of the reservoir by using viscosity-diffusivity wave equation.The model analysis result shows that it is feasible to detect gas-bearing properties of reservoir by using frequency attenuation attributes and low frequency ad joint-shadow phenomenon.Application of real data demonstrates that frequency attenuation attributes and low frequency ad joint-shadow phenomenon has good instruction to the reservoir,and improved the accuracy of reservoir prediction and fluid detection,which can provide a way for oil-gas identification and fluid detecttion of carbonate reef flat lithologic reservoir and similar reservoirs of Changxing Formation in BL area.