As dense seismic arrays at different scales are deployed,the techniques to make full use of array data with low computing cost become increasingly needed.The wave gradiometry method(WGM)is a new branch in seismic tomo...As dense seismic arrays at different scales are deployed,the techniques to make full use of array data with low computing cost become increasingly needed.The wave gradiometry method(WGM)is a new branch in seismic tomography,which utilizes the spatial gradients of the wavefield to determine the phase velocity,wave propagation direction,geometrical spreading,and radiation pattern.Seismic wave propagation parameters obtained using the WGM can be further applied to invert 3D velocity models,Q values,and anisotropy at lithospheric(crust and/or mantle)and smaller scales(e.g.,industrial oilfield or fault zone).Herein,we review the theoretical foundation,technical development,and major applications of the WGM,and compared the WGM with other commonly used major array imaging methods.Future development of the WGM is also discussed.展开更多
An analysis of a passive seismic method for subsurface imaging is presented in which ambient seismic noise is employed as the source of illumination of subsurface scatterers. The imaging algorithm can incorporate new ...An analysis of a passive seismic method for subsurface imaging is presented in which ambient seismic noise is employed as the source of illumination of subsurface scatterers. The imaging algorithm can incorporate new data into the image in a recursive fashion which causes image background noise to diminish over time. Under the assumption of spatially-incoherent ambient noise, an analytical expression for the point-spread function of the imaging algorithm is derived. The point-spread function （PSF） characterizes the resolution of the image, which is a function of the receiving array length and the ambient bandwidth.展开更多
露天矿山边坡矿体内部存在裂隙、节理等岩体结构,对边坡稳定性产生直接或间接的影响。而单一的物探技术只能获取地质结构某一方面的信息,在地质勘探方面存在局限性。为确保边坡稳定,设计一种综合物探技术下露天矿山边坡地质勘测方法。...露天矿山边坡矿体内部存在裂隙、节理等岩体结构,对边坡稳定性产生直接或间接的影响。而单一的物探技术只能获取地质结构某一方面的信息,在地质勘探方面存在局限性。为确保边坡稳定,设计一种综合物探技术下露天矿山边坡地质勘测方法。以地下介质电阻率、密度等地球物理特征为依据,融合瞬变电磁法、高密度电法、地震映像法作为综合物探手段,在Geogiga Front End Free软件工具上,形成地震映像图和视电阻率截面图。根据所得勘测结果显示,通过地震映像法能准确描述出地质形态、地层结构和厚度,高密度电法能够清晰展示出边坡区域下浅层塌陷部分的空间范围及低阻特性明显的填充物,瞬变电磁法能够准确地对超过百米深的地层中的异常体做出响应,证明综合物探技术具有良好的勘探能力。展开更多
文摘As dense seismic arrays at different scales are deployed,the techniques to make full use of array data with low computing cost become increasingly needed.The wave gradiometry method(WGM)is a new branch in seismic tomography,which utilizes the spatial gradients of the wavefield to determine the phase velocity,wave propagation direction,geometrical spreading,and radiation pattern.Seismic wave propagation parameters obtained using the WGM can be further applied to invert 3D velocity models,Q values,and anisotropy at lithospheric(crust and/or mantle)and smaller scales(e.g.,industrial oilfield or fault zone).Herein,we review the theoretical foundation,technical development,and major applications of the WGM,and compared the WGM with other commonly used major array imaging methods.Future development of the WGM is also discussed.
文摘An analysis of a passive seismic method for subsurface imaging is presented in which ambient seismic noise is employed as the source of illumination of subsurface scatterers. The imaging algorithm can incorporate new data into the image in a recursive fashion which causes image background noise to diminish over time. Under the assumption of spatially-incoherent ambient noise, an analytical expression for the point-spread function of the imaging algorithm is derived. The point-spread function （PSF） characterizes the resolution of the image, which is a function of the receiving array length and the ambient bandwidth.
文摘露天矿山边坡矿体内部存在裂隙、节理等岩体结构,对边坡稳定性产生直接或间接的影响。而单一的物探技术只能获取地质结构某一方面的信息,在地质勘探方面存在局限性。为确保边坡稳定,设计一种综合物探技术下露天矿山边坡地质勘测方法。以地下介质电阻率、密度等地球物理特征为依据,融合瞬变电磁法、高密度电法、地震映像法作为综合物探手段,在Geogiga Front End Free软件工具上,形成地震映像图和视电阻率截面图。根据所得勘测结果显示,通过地震映像法能准确描述出地质形态、地层结构和厚度,高密度电法能够清晰展示出边坡区域下浅层塌陷部分的空间范围及低阻特性明显的填充物,瞬变电磁法能够准确地对超过百米深的地层中的异常体做出响应,证明综合物探技术具有良好的勘探能力。
