Research On The Application Of Seismic Inversion In Zhongyu Coal Mine

During of the modern large-scale mine construction and production, we need an accurate understanding of changes in coal thickness for the calculation of coal reserves and the rational arrangement of integrated mining. The past coal thickness prediction methods have large errors and not make full use of seismic and geological data. The seam is a typical low-speed thin, and conventional methods can not identify the coal seam thickness. So in this paper, Using seismic inversion method prediction thin-layer.Firstly, in this paper the principle advantages and disadvantages of the various inversion methods were analyzed, and combined with the actual three-dimensional seismic, well logging, drilling and geological data in Zhongyu coal mine. Selected logging constrained inversion method for the prediction of the thickness of coal seam and sand body.In this article we environment correction and standardization the well logs, to ensure the value of the same constrained inversion curve is the same., Also preprocessing seismic data including interpretation six target layers P1X-P1S, C3t2-C3t. Using the three instantaneous attribute technology, coherence technology and 3D visualization technology implement small-faults and small-structure distribution characteristics. On the basis of standard well logs and fine structural interpretation, we can use well impedance to establish the initial model through interpolated extrapolation, we use 3D-Impedance Inversion method from EPS software, through comparative analysis:the intersection graph of the natural curve and impedance curve can better distinguish coal seam, sandstone and mudstone. Using lithology of the threshold value prediction the thickness of coal seam No.2, No. 9+10 and sand body distribution in Shanxi and Taiyuan formation. Coal thickness calculation methed:Setting the threshold value of the coal, and along the coal to open 5ms up and down, then pick up thickness of the seam time value in the time domain. Finally multiply the velocity of the coal in the synthetic seismograms. We can get the main coal seam thickness of the region.Logging constrained inversion have good correlation with seismic data and its results stability, so it can distinguish the thin layers. However, the application should note the following:the seismic data must be pure wave data of high-fidelity, high signal-to-noise ratio, high-resolution; the initial model accurately established can reduce inversion of multi-solvability, Because of layer control the initial model, so precise layer explanation can improve the seam resolution; adjust the wavelet make the synthetic and seismic records of maximum correlation, Fine calibration of the coal seam, the sophistication of a direct impact on the model reliability.