基于数字检波器的奥灰内部溶洞地震成像技术研究  

Research on seismic imaging technology of karst cave in Ordovician limestone based on digital geophone

作　　者：张宪旭 ZHANG Xianxu(Xian Research Institute Of China Coal Research Institute,Xi’an 710077,China)

机构地区：[1]中煤科工集团西安研究院有限公司,西安710077

出　　处：《物探化探计算技术》2021年第2期194-201,共8页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：淮北矿业集团2018年科学技术项目(2018-05-036)。

摘　　要：针对淮北矿区常规地震勘探中奥灰反射弱且成像效果不佳的问题,在建立奥灰数字模型和总结碳酸盐岩地震响应的基础之上,利用数字检波器无畸变记录低频信息的优势,开展全数字高密度地震勘探处理方法研究,在保护低频、补偿高频、速度更新和偏移等环节进行改进,总结出了一套针对奥灰地层成像的处理方法,获得了煤层下伏奥灰顶界面以及灰岩内部溶洞的成像。结果表明:数字检波器记录的低频信息是解决煤层屏蔽难题的前提,奥灰顶界面的成像是灰岩速度精确求取的关键,叠前时间偏移技术是奥灰内部溶洞成像的核心。This paper aims at the problem of weak reflection and poor imaging effect of Ordovician limestone from conventional seismic exploration in Huaibei mining area.On the basis of building Ordovician digital model,the typical seismic response of carbonate rocks are summarized using the advantage of digital geophone to record low frequency information without distortion,and studying on processing method of all digital high density seismic as well.The key links such as protection low frequency,high frequency compensation,velocity updating and migration were improved.A set of processing methods aiming at the imaging of Ordovician limestone stratum are summarized.Finally,the image of the Ordovician limestone top boundary under the coal seam and the karst cave inside the limestone is obtained.The results show that the low-frequency information recorded by digital geophone is the prerequisite to solve the problem of coal seam shielding.The imaging of the Ordovician limestone top interface is the key for accurate calculation of limestone velocity.The pre-stack time migration technology is the core of the Ordovician limestone cave imaging.

关 键 词：地震勘探 奥灰成像 数字检波器 叠前时间偏移 

分 类 号：P631.4[天文地球—地质矿产勘探]