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为了选择最佳的石灰岩出露区地震资料的采集参数，我们在川东高院构造石灰岩出露区作了近源地震波频谱测试及资料采集试验。其方法是将地震加速度传感器分别置于井下和地表，测试来自不同激发条件（井深、药量及岩性）的近源地震波激发频谱，并与用地震检波器同时接收的地震信号进行对比，以验证其结果的精度。试验结果表明：①山区的低速带，不仅限于表土，而且岩石露头也存在约10m厚的低速带，②受这10m度低速带的影响，在井下和地表测试的激发频谱存在着显著的差异；③三种岩性对高频成分吸收的程度明显不同，其中央岩最严重，砂岩次之，泥岩最弱；④延迟组会爆炸对降低激发频谱、减轻地震波能量的衰减具有明显作用；⑤受低速带的影响，地震波旅行时间、振幅、频率及相位都要发生很大变化。最后指出，要想提高石灰岩出露区原始资料的信噪比，不仅应选择合理的激发参数，而且也要重视接收条件的改善，必要时应考虑将检波器置于井下接收。
In order to select the best acquisition parameters of seismic data in the limestone outcrop area, we conducted near-surface seismic wave spectrum test and data acquisition experiment in the limestone outcropped area of Chon Dong High Court. The method is to place the seismic acceleration sensors in the downhole and the earth’s surface respectively and test the excitation spectra of the near-source seismic waves from different excitation conditions (well depth, dose and lithology) and compare them with the seismic signals received simultaneously by the geophones Verify the accuracy of the result. The results show that: (1) The low speed zone in the mountainous area is not limited to the topsoil, but there is also a low speed zone about 10m thick in the outcrop of the rock. (2) There is a significant difference in excitation spectrum measured downhole and in the surface under this 10m low speed zone. ③ The three rock types absorb the high-frequency components obviously different degree, of which the central rock is the most serious, followed by sandstone, mudstone is the weakest; ④ delay group will explode to reduce the excitation spectrum, reduce the seismic wave energy attenuation has a significant effect; The impact of low speed, seismic wave travel time, amplitude, frequency and phase have undergone great changes. Finally, it is pointed out that if we want to improve the signal-to-noise ratio of the raw data of limestone outcrops, we should not only select reasonable excitation parameters, but also pay attention to the improvement of receiving conditions. When necessary, the geophones should be placed underground for receiving.