Field evidence and thin section observations indicate that the dyke swarms of the EB are similar with those of the WB in distribution characteristics, morphology, petrochemistry, and so on. They were formed in the same mechanism and unified paleostress field, and could be researched as a unit.
The study of the magma flow in the fractures is useful to understand how the dyke swarms form. The researches on the dyke swarms of the EB indicate that the paleostress field offered the space for the magma, and the flow structures of the dykes indicate the magma intruded subhorizontally into the pre-existing fractures.
Some writers have given the result of the simulation of the paleostress field of the NCC (Hou et al., 2006b). The result suggests that extensional fractures were widely formed under the compression from the northern and southern boundaries of the NCC, and offered space for the magma to form the dykes.
Based on the flow structures of the dykes and the previous research on the geochemistry and the magma source, the dyke swarms of the EB are related to the COB similarly as the mafic dyke swarms of the WB.