Taiwan is located on the convergent boundary between the Eurasian plate and the Philippine Sea plate. Plate interaction is marked mainly by the collision of the Luzon volcanic arc and the Asiatic continental margin. The Longitudinal Valley of eastern Taiwan is the suture zone between these two plates in Taiwan. In this plate tectonic event, the Ryukyu Arc is on the east and northeast of Taiwan where convergence is marked by northward subduction of the Philippine Sea plate beneath the Ryukyu Arc on the Eurasian plate along the Ryukyu Trench. The Luzon Arc System is south of Taiwan. In this system, convergence is marked by eastward subduction of the Eurasian plate underneath the Luzon Arc on the Philippine Sea plate (CENTRAL GEOLOGICAL SURVEY, MOEA, n.d.)

Both volcanic arcs extend onto the island of Taiwan. The Tatun Volcano Group, the Chilung Volcano Group, and the northeastern offshore volcanic islands represent the western extension of the Ryukyu volcanic arc. On the other hand, the Chimei Igneous Complex and the southeastern offshore volcanic islands, Lanhsu and Lutao, are all located on the northern extension of the Luzon volcanic arc. Therefore the Cenozoic geology of Taiwan is closely related to the Ryukyu and Luzon arc-trench systems (CENTRAL GEOLOGICAL SURVEY, MOEA, n.d.).