Characteristic Analysis And Application Research Of Reflection Wave Group In Coalfield Subsidence Area

After the underground coal seam is mined,a goaf area is left,which will cause the mechanical balance of the overlying rock layer to be broken,and collapse under the action of its own gravity and external force.The scope of this collapse is the collapse area.The subsidence area is a kind of geological disaster that exists widely in the mining area,which can not only cause damage to local buildings,but also adversely affect the engineering construction.In addition,there are a large number of fissures in the subsidence area,which will also aggravate the deterioration of the geological environment.It can be seen that the existence of the subsidence area has seriously affected people's production and life,and also threatened the safety of people's life and property.Therefore,it is necessary to conduct a scientific and reasonable evaluation of the subsidence area,and timely propose targeted control measures to avoid the occurrence of disasters,and the detection of the spatial distribution of the subsidence area is the key technology for reasonable evaluation.At present,the detection of subsidence areas is mainly based on geophysical exploration technology,among which the seismic reflection wave method has been widely used and achieved good detection results.However,the collapse area is not invariable or in a fixed state.The characteristics of the reflected wave group are closely related to the collapse state,collapse type,existing geological conditions and lithology of the collapse area.It brings a lot of difficulties to the analysis and judgment after detection.Therefore,it is the key to solve this difficulty to analyze and study the characteristics of reflected wave groups in different types of collapse areas and summarize them.This paper mainly relies on the reflected wave exploration data in actual engineering projects,and applies the numerical simulation method based on the finite difference method to establish a variety of geological models of different types of subsidence areas,and carry out numerical simulations on these geological models.Then,carry out detailed analysis of the characteristics of the reflected wave group on the obtained original shot set records and the superimposed sections obtained after a series of data processing,to find the differences and similar points,and summarize their different characteristics and identificationmarks.Finally,according to the analysis results of the numerical simulation of various types of collapse areas,the.inversion results of the actual detection data are effectively interpreted and analyzed,and the number,location,type and overlying influence scope of the collapse areas in the exploration area are determined.It also provides a standard for comparison and analysis for the subsequent detection of the collapse area,thereby reducing the threat of the collapse area.