Abstract:The Nanjing-Wuhu volcanic basin is bounded by the faults stretching mainly in nearly NE and NW directions. Its western boundary, a tension- shearirng fault, is the Yangtze fragmented zone,developed prior to early Tertiary and, with relatively shallow dissection. The eastern boundary, a compresion-shearing fcult, is the Fangshaa-Xiaodasiyang fault, cutting deep- 1y. As the youngest in age, the northern and southern limits belong to the shearing f ault. The volcanic eruption of Cenozoic basalts is considered to be controlled by the characteristics and tectonic evolution of boundary faults, It may be divided into 3 stages: The first eruption occurred during early Tertiary along the Yangtze fragmented zone with a shallower dissection, resulting in the formation of the high-aluminium basalt to the tholeiite. The second took place during late Tertiary along the Fangshan-Xiaodanyang fault, producing the phonolitic tephrite followed,by the alkali-olivine basalt, which are cha- racterized by the presence of the inclusions of mantle-peridotite and the blocks of underlying rocks, hence implying quite a deep magmatic source. The thin d eruption occurred in early Pleistocene and was controlled by inter- section of NW- and EW-trending faults, forming the aitanium-rich phonoli- tic tephr ite. According to the calculating balance of basalts, it is rather difficult to find diamond in these basalts, but a few depth-derived blocks obtained from basalt pipes here indicate that the boundary fault zones may be a possible target for prospecting iron ore-deposits at lower levels in the Nanjing-Wuhu volcanic basin.