由于地震孕育过程的复杂性和观测技术的局限性，不同地震观测资料表现出异常变化与后续较大地震的对应关系存在不确定性，因此对预测意见进行概率表达是一种科学恰当的做法。本文基于泊松分布的危险区背景地震概率预测和单项预测方法（包括测震、流体、形变、电磁等学科）的历史预测效能，采用贝叶斯定理计算得到单项预测方法的短期或年度地震危险概率预测结果，进而采用综合概率方法，给出基于多种单项预测方法的短期或年度地震危险概率预测结果。短期概率预测初步结果表明，2018年2~9月，中国大陆72%的5级以上地震都位于相对高概率预测区域。

The genetic of earthquake is complicate;the observation technique is limited, and the relationship between different observed anomaly and the subsequent earthquake is uncertain. Therefore, probabilistic expression of predictions is a scientific and appropriate approach. In this paper, we calculate the probabilistic prediction results in the risk area suggested by the single prediction method(such as seismicity, underground fluid, deformation, electromagnetic, etc.), taking account of the background earthquake recurrence probability and the forecast efficiency of the corresponding prediction method based on the Bayesian Formula. Then we calculate the earthquake risk probability based on different prediction method by utilizing the comprehensive probability analysis method. In 2018, from February to September, we calculated the probabilistic earthquake prediction for the next every 3 months and for the every 3 months in the next year. Short-term prediction result shows that about 75% earthquakes(M_S ≥ 5.0) in Chinese Mainland are distributed in the relative high probability region.

P315

国家重点研发计划课题“年尺度和短临强震发震紧迫程度判定技术研究”（2017YFC1500502）、中国地震局震情跟踪定向工作任务（2019010118）共同资助