Research And Implementation Of Six-component Geophone

As one of the effective methods for gasoline resource exploration,seismic survey has been widely used.The geophone is the core component of the seismic exploration instrument system.At present,single-component and three-component seismic exploration has entered the stage of industrial application,and has made considerable contributions to the development of gasoline in China.However,under the influence of complex geological environment,stratum structure and other factors,the interpretation processing of the obtained seismic data is difficult,and the imaging accuracy of formation inversion is poor.The reason is that the current single-component and three-component seismic surveys lack seismic wave rotation vector information.Therefore,in complex mountainous environment exploration operations,new requirements are placed on exploration equipment and methods,that is,obtaining maximum seismic wave vector information.According to the demand for seismic exploration in complex mountains,this article is based on the National Natural Science Foundation of China "a method of simultaneously acquiring seismic wave displacement vector information and rotation vector information" to design a new type of simultaneous acquisition of seismic wave displacement vector and rotation vector six-component geophone.We chiefly got the following research achievements:(1)The design of front end acquisition circuit,using MEMS sensors and 24-bit ?-? AD exclusively used in seismic exploration to achieve high dynamic range,high sampling rate,and wide band data output.To further improve the quality of seismic data acquisition,we used programmable chip design to control simple,low-noise signal processing circuit.(2)We used a three-stage cascade connection structure in the design of the digital decimation filter based on FPGA.It not only simplifies the filter design,but also conspicuously reduces the total operand of the smoothing extraction and the memory space occupied by the system.Compared with the dedicated hardware extract the chip of filter,this design not only saves the space of detectors,but also effectively reduces the cost.(3)We adopted asynchronous FIFO to achieve data synchronization in different clock domains,based on the development of FPGA seismic data transmission controller signals.It effectively reduces the occurrence of metastable status of data crossing clock domains.In addition,we designed SDRAM data stored logic,solving the problems of multi-channel data storage,and reducing the probability of errors caused by true time data upload.Through performance testing and experiments on the completed system prototype,the displacement vector information and rotation vector information can be obtained simultaneously,and The dynamic range of the detector is more than 130 d B,and the harmonic wave distortion is less than-100 d B,which can satisfy the needs of complex mountain seismic exploration.