菱铁矿经过适当温度热处理后的异常等温剩磁（ＩＲＭ）曲线的全部形态与初始剩磁态的３个集合相对应。根据ＩＲＭ曲线存在负微商线段这一事实，提出有逆磁相存在，并用正常磁相和逆磁相的耦合来解释这种异常等温剩磁行为。这种逆向剩磁是在室温下获得的，在磁化时没有任何热过程和化学过程发生，在本质上与已观察到的逆向热剩磁和逆向化学剩磁不同。 The total IRM curve of siderite after appropriate temperature heat treatment corresponds to the three sets of initial remanence. According to the fact that the negative derivative line exists in the IRM curve, this paper proposes the existence of the inverse magnetic phase, and uses the coupling of the normal magnetic phase and the inverse magnetic phase to explain this abnormal isothermal remanent magnetization. This reverse remanence is obtained at room temperature without any thermal or chemical processes during magnetization and is essentially different from what has been observed in reverse thermal remanence and reverse chemical remanence.