江苏数字地震台网台址噪声谱分析

江苏数字地震台网已建设改造了 8个台站。对 8个台站记录到的背景噪声进行定量分析 ,测定背景噪声的地动速度均方根值 (RMS)、有效测量动态范围 (D有效)和噪声功率谱。结果表明 :受台基和海潮等观测环境的影响 ,大部分台站的地动速度RMS值高于 2 × 1 0 -8m/s,降低D有效 值。背景噪声功率谱峰值频率为 2 5～ 3 0Hz。这些定量分析为了解数字地震台网的实际监测水平提供了可靠依据

Spectral analysis of noises recorded at station sites of the Jiangsu Digital Seismological Network

stations have been built or rebuilt for the Jiangsu Digital Seismological Network The background noises recorded at the 8 stations have been analysed quantitatively and the square root of mean square (RMS) values of the ground motion velocities of the background noise,the dynamic ranges of the effective measurements (D eff ) and the power spectra of the noises have been determined The results have shown that due to the influences of the observational environment such as the ground conditions of stations and sea tides,the RMS of the ground motion velocities at most stations are greater than 2×10 -8 m/s,thus the D eff values are reduced The frequences of the peaks in the power spectra of the background noises range between 2 5～3 0 Hz Results of these quantitative analyses have provided reliable basis for understanding the real monitoring capability of the digital seismological network