中国是世界上地震多发的地区之一。在各省份中，处于中国西南部的云南省是地震发生最多的省份之一。云南省省会昆明以南60 km处的抚仙湖位于小江地震带和通海-石屏地震带的交汇处，该地区的地震频次又居云南省之首。如果能在抚仙湖的沉积物中找到历史地震的自然记录并解释其机理，就意味着发现了一个由抚仙湖自然形成的地震记录仪。提供了证明抚仙湖区域历史地震自然记录存在的证据---抚仙湖沉积物的磁化率。我们在抚仙湖的中心地带、水深108 m处，钻取到了170 cm长的抚仙湖沉积物剖面，经测试证明它对应着近1 000年，约公元1025年至今的沉积年代。在研究中，沉积物磁化率的峰值突变与过去1 000年中许多有历史记载的地震事件相吻合。此外，一些尚没有记载的古地震事件也通过对湖底沉积物磁化率的分析而得以发现。

China is one of the countries in the world with a frequent occurrence of earthquakes. Among all provinces in China, Yunnan province in southwest China has the most frequent occurrence of earthquakes. Located 60 km south of Kunming, the capital city of Yunnan province, Fuxian lake is situated in a region where the Xiaojiang earthquake belt and the Tonghai-Shiping earthquake belt intersect. The Fuxian lake area is the region in Yunnan that has the most frequent occurrence of earthquakes. If we could find a natural recorder of historical earthquakes in the lake deposits of Fuxian lake and explain its mechanism, it means that we have discovered a seismic detector installed by nature in Fuxian lake. It is therefore important for us to discover the evidence in nature. In this paper, proven evidence has been found for the existence of a natural recorder of historical earthquakes in Fuxian lake area—the magnetic susceptibility of lake sediments in Fuxian lake. A 170 cm-long sediment core was taken from Fuxian lake, which was tested to be representing the sedimentation for the past one thousand years from 1 025 to now. In our research, the magnetic susceptibility peaks of the lake sediments correlate to many earthquakes recorded in history that occurred during the past one thousand years. In addition, earthquakes without a record in history have been recovered by testing the magnetic susceptibility of the lake sediments.