Spectral decomposition technology has been successfully used in the conventional oil and gas and marine facies shale gas ex⁃ploration and development, but it has not been yet used in continental shale gas exploration practice. The seismic spectrum curves in different fluid reservoirs have different characteristics in such aspects as shapes, slopes, values of dominant frequency and central fre⁃quency. According to these features, continental seismic spectrum properties of mud shale in the Middle Jurassic Dameigou Forma⁃tion of Yuqia sag within northern Qaidam Basin were identified, and gas potential was predicted. The results suggest that the energy coefficient is low in the upper part of Middle Jurassic Dameigou Formation with an average of 0.6719, while it is high in the lower part with an average of 0.7521. The gas content in the field and the total hydrocarbon characteristics show that the gas content in the lower part is better than that in the upper part, with the energy coefficient of 0.7 as the boundary. On such a basis, two favorable tar⁃get areas were delineated and one of them was drilled as Chaiye 1 well. Therefore, spectral decomposition technology can be used in continental shale gas exploration and development.%针对柴达木盆地北缘鱼卡凹陷中侏罗统大煤沟组泥页岩，利用地震频谱曲线在不同流体介质储层中的形态、斜率、主频与中心频率的差值等属性参数特征，识别陆相泥页岩层系的地震频谱属性特征，预测含气性。研究结果表明，中侏罗统大煤沟组上部能量系数较低，平均为0.6719，下部能量系数较高，平均为0.7521，结合现场含气量和全烃特征认为，可以以能量系数0.7为界线，作为识别下部和上部含气性的标志，下部明显比上部含气性好。平面上进一步圈定了2个有利目标区，得到柴页1井勘探验证。因此，频谱分解技术可应用于中国陆相页岩气的勘查开发。
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