Panxi Rift with the dome-shaped volcano pattern has undergone three evolutionary processes：the lithosphere dome by mantle bulge, the continen- tal crust dome and the subvolca,no-dome, With the dome structure develop- ang, the magmatism gradually evolved from deep-seated matte source, mid- hypabyssal mantle source assimilated and contaminated by the continental crust to super-hypabys}al mantle source mixed with the crust.So we believe that there exist two-times magma chambers of lower, middle and high seats under the Rift during the developmental stage of the Rift with dame-sha- ped volcano pattern, The primary magma rising to the surface from the magma source had suffered stagnation, tra.etional crystallization and assimi- lative五ybridization of the continental crust in chambers at different depths, therefore it might have produced different paragenetic association types of the equilibrium minerals and different trends of the magmatic differentia- tion, Panxi Rift belongs to undeveloped type but with longer evolutionary time. It has a geological history about 200 million years(418-21OMa)，evo- lying from the lithosphere dome by mantle diapir (O-S)-the continental crust dome(D-C)一the continental crust fracture(P)-the subvolcano dome