公开(公告)号：US10393901B2

公开(公告)日：2019-08-27

申请号：US15238460

申请日：2016-08-16

Applicant: PGS Geophysical AS

Inventor： Shaoping Lu ,  Norman Daniel Whitmore, Jr. ,  Alejandro Antonio Valenciano Mavilio ,  Nizar Chemingui

IPC: G01V1/32 ,  G01V1/36 ,  G01V1/38

Abstract: Methods and systems of generating seismic images from primaries and multiples are described. Methods separate pressure data into up-going pressure data and down-going pressure data from pressure data and vertical velocity data. Irregularly spaced receiver coordinates of the down-going and up-going pressure data are regularized to grid points of a migration grid and interpolation is used to fill in down-going and up-going pressure data at grid points of the migration grid. A seismic image is calculated at grid points of the migration grid based on the interpolated and regularized down-going pressure data and the interpolated and regularized up-going pressure data. The seismic images are high-resolution, have lower signal-to-noise ratio than seismic images generated by other methods, and have reduced acquisition artifacts and crosstalk effects.

公开(公告)号：US20190187312A1

公开(公告)日：2019-06-20

申请号：US16221128

申请日：2018-12-14

Applicant: PGS Geophysical AS

Inventor： Jaime Ramox-Martinez ,  Alejandro A. Valenciana Mavilio ,  Nizar Chemingui

IPC: G01V1/28 ,  G01V1/38 ,  G01V1/30 ,  G01V1/20

CPC classification number: G01V1/282 ,  G01V1/201 ,  G01V1/303 ,  G01V1/3808 ,  G01V1/3843 ,  G01V2210/671 ,  G01V2210/675 ,  G01V2210/74

Abstract: This disclosure describes processes and systems for generating a high-resolution velocity model of a subterranean formation from recorded seismic data gathers obtained in a marine seismic survey of the subterranean formation. A velocity model is computed by iterative FWI using reflections, resolving the velocity field of deep subterranean targets without requiring ultralong offsets. The processes and systems use of an impedance sensitivity kernel to characterize reflections in a modeled wavefield, and then use the reflections to compute a velocity sensitivity kernel that is used to produce low-wavenumber updates to the velocity model. The iterative process is applied in a cascade such that position of reflectors and background velocity are simultaneously updated. Once the low-wavenumber components of the velocity model are updated, the velocity model is used as an input of conventional FWI to introduce missing velocity components (i.e., high-wavenumber) to increase the resolution of the velocity model.

公开(公告)号：US20150362611A1

公开(公告)日：2015-12-17

申请号：US14550001

申请日：2014-11-21

Applicant: PGS Geophysical AS

Inventor： Didier B. P. Lecerf ,  Nizar Chemingui ,  Alejandro A. Valenciano Mavilio ,  Shaoping Lu

IPC: G01V1/34

CPC classification number: G01V1/28 ,  G01V2210/1293 ,  G01V2210/1423 ,  G01V2210/56 ,  G01V2210/57

Abstract: Techniques are disclosed relating to geophysical analysis. In one embodiment, a method includes receiving seismic data for a geophysical formation recorded during a seismic survey using one or more seabed sensors and one or more sources. In this embodiment, the method includes determining a seismic gather for a location in the geophysical formation, modifying the seismic gather by interchanging source-receiver definitions for the seismic gather, and imaging the location using the modified gather. In this embodiment, the imaging uses higher-order reflections recorded in the seismic gather. In some embodiments, the method includes separating up-going and down-going wavefields and separately imaging using the up-going wavefield and the down-going wavefield.

Abstract translation: 公开了与地球物理分析有关的技术。 在一个实施例中，一种方法包括使用一个或多个海底传感器和一个或多个源接收在地震勘测期间记录的地球物理地层的地震数据。 在该实施例中，该方法包括确定用于地球物理地层中的位置的地震采集，通过交换地震采集的源 - 接收机定义来修改地震采集，以及使用修改的集合对位置进行成像。 在该实施例中，成像使用记录在地震采集中的高阶反射。 在一些实施例中，该方法包括使用上行波场和下行波场分离上行和下行波场并分开成像。