The Luzong basin locates at northeastern margin of the Yangtze craton and the foreland area of the DabieSulu orogen, and convergent section of the Tanlu fault and the Yangtze River fault, is a typical tectonic place. The volcanicsubvolcanic rocks in the basin are characterized by highK and rich in alkali, belong to typical shoshonite series. In geochemistry, these rocks exhibit obvious depletion in highfieldstrongelements (HFSE) such as Nb and Ta, enriched in strong incompatible elements such as Rb, Th, U and K as well as light rare earth elements (LREE). Nd and Sr isotope compositions of the rocks indicate that their parental magma mainly formed by partial melting of the enriched subcontinental lithospheric mantle. The volcanic rocks developed in the Luzong basin can divided into Longmenyuan Formation, Zhuanqiao Formation, Shuangmiao Formation and Fushan Formation respectively from early to late, with clear extrusive gap among different Formations. In this work, we used zircon SHRIMP UPb technique accurately dating samples from four Formations in the Luzong basin, yield emplacement ages of 131±1 Ma, 133±1 Ma, 130±1Ma and 127±1 Ma respectively, show that whole volcanic rocks in the Luzong basin formed in a very short period of time (≤6 Ma). These data, combined with the time of whole volcanism in the Middle and Lower Yangtze River reaches, predicate an "sudden" volcanic event, imply delamination as the main model for lithospheric thinning of the region (and the whole lower Yangtze region).