采空区勘查新技术及应用

Seismic scattering technology and its application in goaf exploration

采空区危害巨大,但常用物探方法往往难以准确探测.为了寻找适合的采空区探测物探方法,本文介绍了基于散射地震理论的SSP地震散射技术的原理和技术要点,SSP技术以非均匀地质模型为基础,适应复杂地质、地形条件;通过波场分离、速度分析、偏移成像技术,可得到地层的波速分布与地质界面分布图像.同时本文结合实例研究了SSP技术在采空区勘查中的应用效果.结果表明:相比于反射地震方法将时间同相轴形态变化作为判定采空区标准,SSP技术依据低速区分布判定采空区的方式更加直观、准确;并结合界面形态综合解释采空区,进一步提高了勘探的准确度;该方法具有分辨率高、探测深度大等特点;在应用中取得了令人满意的结果.

Goafs have great impact on the mine safety and engineering. Goals could lead to shock bump, gush out, rock burst, ground subsidence, landslide, or decrease of planting land. At present, goafs lead to many hazard in China. Exploration of goals is essential for mine disasters prevention and engineering safety. But goafs detection is a difficult probleM. There is no appropriate geophysics method to explore goals, especially when the geological or terrain conditions are complex or when goafs are lack of groundwater. It is because that frequently used geophysics method, for example, seismic refection method and electromagnetic methods are not effective for detecting goals. As a new seismic exploration technique, SSP seismic scattering technology is based on inhomogeneous geological model. So it is suitable for the complex terrain, geological conditions. Profit from wave field separation technology, velocity analysis technology and migration imaging technology, SSP seismic scattering technology can get seismic velocity distribution, geological interfaces ~ morphology and geological interfaces ~ mechanical property of underground medium. And these geological characteristics and information help us to interpret goals. This paper also introduces the application effect of goals~ exploration with an example. The results indicate that, compared with seismic reflection method, SSP technology take low velocity zone as the main indicator of goal, And the result of SSP is more intuitive than reflection method. If we take geological interfaces＇ morphology as another indicator of goal, too, the result can be more sufficient. In addition, SSP technology has high resolution and deep probing depth. Because of these characteristics, SSP seismic scattering technique has great advantages in exploration of goals After many practical application, satisfactory results are obtained.