表层Q值确定性求取与空变补偿方法

实际地震资料处理中，基于地层吸收补偿的传统方法大多数偏于解决中、深层地层的吸收衰减问题，没有考虑速度、厚度变化剧烈的近地表吸收衰减作用，因此不能获得令人满意的结果。为此，提出了一种基于近地表模型的确定性定量补偿方法，该方法基于地表一致性原理，引入表层相对衰减系数的概念，在共炮检域迭代计算相对衰减系数，结合表层旅行时求表层相对品质因子Q，由实测的绝对Q约束标定相对Q，建立表层Q模型，然后实现稳定的表层Q时空变补偿。经模型数据和实际数据验证，所提方法具有较高的计算精度，目前在多个地区实际资料应用取得了实质性效果。

Near-surface Q value estimation and quantitative amplitude compensation

Most strata compensation methods only consider the middle and the deep absorption rather than the strong lateral velocity and thickness variations at the near-surface,so the results are not satisfactory.To solve the problem,we propose a deterministic quantitative compensation method based on near-surface model to realize quantitative Q prediction and space-time variation compensation.Based on the principle of surface consistency,the conception of surface relative attenuation coefficient is introduced.A relative attenuation coefficient is calculated with statistics iterations in the common offset domain,and a near-surface relative Q is obtained.Then the near-surface relative Q is calibrated with the measured absolute Q and a near-surface Q model is built.Finally,a stable near-surface Q space-time variation compensation is realized.Model tests verify the high accuracy of the proposed method,and 3D seismic data applications in a few oil fields prove the validity of the proposed method.