排序方式： 共有3条查询结果，搜索用时 15 毫秒
1
1.
在克希霍夫叠前时间偏移处理中，地震波走时的计算方法是决定大偏移距地震资料成像品质的重要因素.在常规的三维转换波各向异性叠前时间偏移公式中，走时的计算是基于等效单层各向异性介质的非双曲线方法.用这种方法处理的成像道集，在偏移/深度比超过一定阈值后，成像道集中的反射同相轴将出现过偏现象，这种偏移不平的同相轴将影响偏移叠加的最佳响应，使得偏移成像波组呈低频化特征，最终降低三维转换波偏移成像质量.我们采用层状介质的走时计算方法代替常规算法，并且利用了常规方法的转换波各向异性偏移速度模型.基于层状介质的算法能够提高大偏移距转换波走时计算精度，克服中浅地层大偏移距远道成像道集中反射同相轴逐渐上翘的问题.两个地区的三维转换波资料处理结果证实，基于层状各向异性介质的转换波克希霍夫叠前时间偏移方法，明显改善了反射成像剖面的连续性和分辨率，提高成像剖面构造的可解释性. 相似文献
2.
Spectral decomposition using the method of Matching Pursuit Decomposition （MPD） for PP- and PS-wave data has higher resolution and higher consistency over the entire time-frequency plane. The MPD algorithm avoids the problems of inaccurate analytic time point and the time window size choice that may occur during a Fourier transform. The PP-wave attenuation is greater than the PS-wave attenuation while propagating through gas reservoirs. There are some stronger amplitude low-frequency shadows on the PP-wave single frequency sections beneath gas reservoirs which are not seen on corresponding PS- wave single frequency sections. Therefore, hydrocarbons are predicted from comparing the behavior on both frequency sections. The time-frequency analysis for multi-component data is decomposed by MPD for data from northeast China containing rich gas reservoirs. The gas response character is analyzed on different wave mode single frequency sections. We describe the MPD algorithm, compare it to other spectral decomposition methods, and show some examples of detecting low-frequency shadows beneath gas reservoirs. 相似文献
3.
应用拟合追逐分解MPD(Matching pursuit decomposition)法对地震数据进行谱分解能够提供更好的分辨率,在时间分辨率和频率分辨率上到达一致,避免付氏变换方法中时窗大小选择和分析时间点不准确的问题。含气地层对纵波资料产生较大的频率衰减,在储层下方可能见到低频强振幅的低频阴影现象。而转换波资料受气藏影响小,在转换波剖面中不会出现同纵波类似的低频阴影区。因此,综合两种资料在分频剖面上的表现,可以进行含气性异常的预测。对已知气藏的实际多波地震资料,进行MPD分频处理,在不同波场的分频剖面上,分析气层响应特征。 相似文献
1