基于高斯束偏移方法的远偏移距构造成像研究  

Research on imaging construction with far offset distance based on Gaussian beam offset method

作　　者：霍亮 杨飞龙 张慧莉 房文振 HUO Liang;YANG Feilong;ZHANG Huili;FANG Wenzhen(School of Earth Sciences and Engineering,Xi'an Shiyou University,Xi'an Shaanxi 710065,China;Shaanxi Key Laboratory of PetroleumAccumulation Geology,Xi'an Shaanxi 710065,China)

机构地区：[1]西安石油大学地球科学与工程学院,陕西西安710065 [2]陕西省油气成藏地质学重点实验室,陕西西安710065

出　　处：《石油化工应用》2024年第10期44-49,共6页Petrochemical Industry Application

摘　　要：VSP高斯束偏移方法是一种高效和高精度的地震成像方法,可以获得井旁的高精度结构特性。然而,传统一次反射偏移方法受观测系统的限制,无法在远距离处成像地层结构。VSP一阶表面多次波可以有效扩大远距离成像范围。本文提出了一种VSP高斯束偏移方法来成像VSP数据中的一阶表面多次波。首先,优化了VSP观测系统的平面波分解算法,在井口接收的地震波场用高斯窗函数分解为不同方向的平面波。其次,对速度模型进行镜像,并应用反褶积独立成像每个方向的平面波。最后,通过对VSP速度模型和检波点坐标的镜像,将VSP自由表面多次波转换为一次反射波,并利用VSP一次反射波高斯束偏移方法对一阶表面多次波进行成像。模型和数据验证了所提出方法的有效性和可靠性。VSP Gaussian beam offset method is an efficient and high-precision seismic imaging method that can obtain high-precision structural characteristics near boreholes.However,traditional single-reflection migration methods are limited by the observation system and cannot image distant stratigraphic structures.VSP first-order surface multiples can effectively extend the imaging range to greater distances.This paper proposes a VSP Gaussian beam offset method to image first-order surface multiples in VSP data.First,the plane wave decomposition algorithm of the VSP observation system is optimized.The seismic wavefield received at the wellhead is decomposed into plane waves in different directions using a Gaussian window function.Then,the velocity model is mirrored,and deconvolution is applied to independently image the plane waves in each direction.Finally,by mirroring the VSP velocity model and geophone coordinates,the VSP free surface multiples are converted into primary reflections,and the VSP Gaussian beam offset method for primary reflections is used to image the first-order surface multiples.Models and data verify the effectiveness and reliability of the proposed method.

关 键 词：VSP高斯束 一阶表面多次波 远偏移距 速度镜像 

分 类 号：TE132.14[石油与天然气工程—油气勘探]