使用连续1000hr的数据计算甚宽频带地震计自噪声，应用概率统计方法对计算结果进行分析，分别以单小时结果众值、单频点概率统计及分频带概率统计等3种表达方式对分析结果进行展示。通过比较分析，发现第1种方式便于异常结果溯源，但无法获取自噪声非均匀分布特征；第2种方式可以获取固定频点上自噪声水平非均匀分布的详细特征，但高概率值呈现条带分布，没有明显量级差异；第3种方式得到了对应于中心频点的且具有量级差异的高概率值，为地震计自噪声的数学数值建模提供了支持。在异常数据数量较少的情况下，异常结果在后2种方式中得不到体现。

we calculated the seismometer's self-noise level with 1000 consecutive hours of data, and proposed using the probability and statistics method to analyze the calculation results. the analysis results are demonstrated by three expressions:multi-hour result overlap, probability statistics on single frequency point and probability statistics in subband. Through the comparison and analysis, we found that it is easy to track anomalies but hard to get the non-uniform distribution characteristic for the first expression. For the second one, it is easy to get the non-uniform distribution characteristic of the self-noise level at the fixed frequency point without obvious difference in orders of magnitude. the third method is to obtain a high probability value corresponding to the center frequency point and having a magnitude difference. In the case of a small amount of abnormal data, the abnormal results are not reflected in the latter two ways.

P315

河北省地震局星火计划重点项目“宽频带地震计低频段自噪声水平检测技术研究”（DZ20160621074）、河北省地震局测震专业仪器系统检测评估与观测场地遴选创新团队、中国地震局地震科技星火计划项目“我国东部陆地及近海地区背景噪声源的定位与特性研究”（XH19014）共同资助