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对辽西四合屯剖面合化石层及其下伏和上覆玄武岩进行了较为详细的岩石磁学和古地磁学研究，结果表明含化石的沉积岩层段和下伏玄武岩段具有正极性，上覆玄武岩则具有负极性．结合最新的同位素测年结果可知，含化石层段的古地磁极性年龄为早白垩世Ｂａｒｒｅｍｉａｎ阶Ｍ３ｎ极性时．岩石磁学参数测量结果揭示出该湖相沉积岩中夹有数层火山凝灰质沉积物，这可能说明由火山活动等地球深部动力学过程引起的剧烈环境变化与古湖区生物的剧生剧灭有关．
The authors conducted a detailed study of rock magnetism and paleomagnetism in the Siheitun coherency layer and its underlying and overlying basalts in Western Liaoning Province. The results show that the fossiliferous sedimentary rock layers and the underlying basalts have positive polarity, Basalt has a negative polarity. According to the latest isotopic dating results, it can be seen that the paleomagnetic geochronology of the fossil-bearing intervals is at the Early Cretaceous Barremian M3n polarity. The measurement results of rock magnetic parameters reveal that there are several layers of volcanic tuffaceous sediments in the lacustrine sedimentary rocks, which may indicate that the violent environmental changes caused by deep Earth's dynamical processes such as volcanic activity are related to the dramatic extinction of ancient living creatures.