椭球定位速度分析方法在黑松驿地区超前预报中的应用  

Application of ellipsoidal positioning velocity analysis method in advance forecast in Heisongyi area

作　　者：高振 王伟[2] 王祥春[1] 李开富 GAO Zhen;WANG Wei;WANG XiangChun;LI KaiFu(School of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China;State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Science and Natural Resources Research,CAS,Chaoyang District,Beijing 100101,China;Company Profile of China Railway Engineering Services Co.,Ltd.,Chengdu 610000,China)

机构地区：[1]中国地质大学(北京)地球物理与信息技术学院,北京100083 [2]中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室,北京100101 [3]中铁工程服务有限公司,成都610000

出　　处：《地球物理学进展》2023年第2期790-802,共13页Progress in Geophysics

摘　　要：超前地质预报中,地震波速度信息是预报隧道前方地质危害的重要载体或评价指标.速度模型不仅影响偏移成像效果,还影响着预报解释的可靠性.由于超前预报观测系统和探测方向是同向的,传统基于拉平同相轴的速度分析方法不适用于此.本文提出椭球定位速度分析方法,依据超前预报观测系统特点,结合三分量数据方向约束,来确定地层射线平均速度,可准确反演空间速度模型.建立典型破碎带地质模型,通过波场快照与地震数据对比分析,表明正演结果的准确性.通过对模型正演数据和工程实例数据的速度分析,研究结果表明,椭球定位速度分析方法在超前预报中,能获得掌子面前方准确的速度分布,利用速度和波速比信息判定异常体破碎程度、含水性、岩性变化,并提高了预测准确性.In advance geological prediction,seismic wave velocity information is an important carrier or evaluation index for predicting geological hazards in front of the tunnel.The velocity model influences not only the migration imaging effect,but also the predictability and interpretation of results.The traditional velocity analysis method based on flattening the in-phase axis is unsuitable for this because the advance prediction observation system and the detection direction are in the same direction.In this paper,proposed an ellipsoidal positioning velocity analysis method to determine the mean velocity of stratigraphic rays based on the characteristics of the over-the-top expedition observation system,combined with three-component data direction constraints,which can accurately invert the spatial velocity model.The accuracy of the orthorectified result was determined by establishing a geologic model of a typical rock fracture zone and comparing and analyzing wavefield snapshots with seismic data.Through velocity analysis of manually established model orthorectified data and engineering example data,the research results show that the ellipsoidal localization velocity analysis method can obtain accurate velocity distribution in front of the palm face in overcasting,determine the degree of anomaly fragmentation,water content,and lithological changes using wave velocity ratio information,and improve the prediction accuracy.

关 键 词：地质超前预报 地震 反射波法 速度分析 

分 类 号：P631[天文地球—地质矿产勘探]