Description

As special results in extensional setting, the mafic dykes comprise lamprophyres, dolerites and diabase porphyrites. It is generally accepted that Mesozoic destruction accurred in the North China Craton, large-scale investigation on this have been done at the same time, however, controversies on the age, space, meachnism and contral factors appear due to minor investigation on the mantle-derived rocks. As one important Fault in the North China Craton, Mesozoic mafic dykes are widespread in the Tancheng-Lujiang Fault, indubitably, the special studies on these dykes can provide important evidence for the destruction of the NCC. This study using geochronological, geochemical, and whole-rock Sr-Nd-Pb isotopic data of the Mesozoic mafic dykes from the Tancheng-Lujiang Fault. Based on the systematic study, the main results are as follows: the mafic dykes were derived from the partial melting of an enriched mantle source due to the hybridization of subducted sedimentary rocks from Yangtze Craton during 122-125 Ma. In addition, the parental magmas of these dykes then fractionated olivine and Fe-Ti oxides during ascent and underwent negligible crustal contamination during magma emplacement.