关键词: 基性岩墙群, 燕辽-中条拗拉谷, 磁组构, 流动构造, 侵位机制

Abstract: Mesoproterozoic mafic dyke swarms are extensively developed in the Western Shandong, the east of the North China Craton, which intruded the Early Precambrian crystal basement. The dorminant orientation of these mafic dykes is nearly N-S trending. The mafic dyke swarms in the Western Shandong belong to LREE enrichment magmatic rocks, and are formed in a continental rift environment according to petrology and geochemistry of these mafic dykes. The flow structures and geometry evidences of the dykes indicatethat the magma source of these dykes intruded the pre-existingtensional rupture . The dyke swarms in the Western Shandong intruded from North to South. Angles between the long axis orientations of magnetic fabric textures and the middle line of dykes suggest that the flow direction of these dykes is from North to South. Further it indicate that the dykes intruded fromNorth to South. These flow structures, geochemistry and magnetic fabric textures suggest that magma come from enriched mantle magma source beneath the Yanliao-Zhongtiao aulacogens based on space-time relationship between the mafic dyke swarms and Yanliao-Zhongtiao aulacogens.

Key words: mafic dyke swarms, Yanliao-Zhongtiao aulacogens, magnetic fabric, flowstructure, emplacement mechanism