On the Debao platform margin, the authors firstly discover numerous multi-phased limestone dikes of the Lower Carboniferous Tournaisian stage in the Devonian limestone. The shapes, sedimentary characteristics, age and distribution pattern of the dikes are made clear. The authors have found many conodonts of Early Carboniferous as well as the phenomena that Gnathodus and Siphnodella mixed in sedimentary dikes. The authors get a new understanding for the genesis of the dikes. The dykes are the incorporation products of tectonic movements and earthquakes.