LAUSR

Abstract Combining published age data and geological maps, we provide most updated information about the spatio-temporal distributions of Mesozoic granitoids and volcanic rocks in SE China. The outcrop areas of the Mesozoic felsic magmatic rocks with an interval of 10 Myrs are estimated, allowing us to put forward by far the finest evolution pattern of the spatio-temporal distributions of the Mesozoic magmatic rocks, which were not available before. The Early Mesozoic (Indosinian) felsic magmatic rocks originally occurred sporadically in the South China block, and then showed a NE-trending distribution followed by an outward (in particularly northeastward) migration. Subsequently, there was a relative magmatic quiescence from 210 Ma to 180 Ma which was followed by a tectonic transition from Tethys regime to Paleo-Pacific regime at 180–170 Ma (probably very close to 170 Ma). The Late Mesozoic (Yanshanian) magmatic activities also showed an outward expansion and migration. The 170–150 Ma magmatic activities migrated from present inland to the northeastern and coastal areas of SE China, with outcrop area increasing gradually. While the 150–120 Ma felsic magmatic activities showed dominantly a northeastward migration, with outcrop area decreasing gradually. Till the period 120–80 Ma, the felsic magmatic activities migrated to the present southeast coastal areas with increasing intensity of volcanic activity. Based on the detailed spatio-temporal evolution, we suggest that the formation of Mesozoic granitoids and volcanic rocks in SE China was related to multiple stages of subduction and roll-back of oceanic slab on the southeast margin of the South China Block.