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辽西地区广泛发育中生代火山岩，其中以义县旋回火山岩最为发育。本文在对辽西地区义县旋回火山岩微量元素地球化学特征研究的基础上，认为义县旋回火山岩具有同源性质，由壳幔混溶物质作用于统一的火山活动过程中产生。火山活动总体逐渐减弱，前期以部分熔融作用为主，后期发生了结晶分异作用。所建立的详细的微量元素变化剖面很好地反映了本旋回火山活动具有脉动性的特点。火山活动形成于与俯冲作用有关的远离大陆活动边缘的板内环境，处在由区域的挤压应力场向拉伸应力场转变期之后，这种转变可能与岩石圈的拆沉作用有关。
Mesozoic volcanic rocks are widely developed in western Liaoning, of which cyclotron volcanic rocks are the most developed in Yi County. Based on the study of the trace element geochemical characteristics of the Yixian cyclotrion volcanic rocks in western Liaoning Province, this paper argues that the Yixian cycle volcanic rocks have the same source and are produced by the action of the crust-mantle mixed material on a unified volcanic activity. The volcanic activity is generally weakened gradually, mainly by the partial melting in the early stage and the crystallization differentiation in the late stage. The detailed profile of trace elements established reflects the pulsatile nature of this volcanic volcano. The volcanic activity is formed in the intraplate environment far from the edge of the continental activities related to the subduction, which may be related to the delamination of the lithosphere after the period from the compressive stress field to the tensile stress field in the region.