Objective The purpose of this study is to explore the formation mechanism and dynamic background of Changma kimberlite, enhancing the research level of kimberlite-type diamonds to facilitate new breakthroughs in mineral exploration.

Methods Based on petrogeochemistry and inclusion analysis of Changma kimberlite in western Shandong Province, combined with published Sr−Nd−Hf isotopic data.

Results The MgO content of Changma Kimberlites has the range of 21.78%~29.67%, with the average value of 26.41%; the CaO content varies between 6.41%~12.85%, with the average value of 9.31%, which has the characteristics of primitive magma, Nb/Ta is 13.74~15.0, the average is 14.23, Nb/U is 32.1~35.42, the average value is 34.07, Fe/Mn is 54.68~97.87, the average is 69.70, CaO/Al₂O₃ is 2.02~4.28, the average is 2.98, CaO/TiO₂ is 2.82~9.18, the average is 4.89. The kimberlites show negative anomaly of K, Ba, Hf and enrichment of the light rare earth elements, with ∑LREE/∑HREE varying from 28.81~37.51.

Conclusions The discovery of coesite inclusions in diamondiferous kimberlites suggests that the source region has contributions from continental or oceanic crustal materials. Sr−Nd−Hf isotope studies document the participation of recycled crust−sourced multicomponents in the formation of kimberlites. Based on the above evidence, it is concluded that the formation of Changma kimberlites in Western Shandong is closely related to the subduction of the Proto−Tethys Ocean (520~460 Ma). It provides a new idea for the exploration of kimberlite−type diamond deposits.