摘要
Mafic dikes are found forming in different periods of the Mesozoic in Southeast China. Ages of the dikes show a spatial variation as that of the Mesozoic granites of this area. Mafic dikes usually occurred limited in tensional cracks developed within granite bodies, seldom to perforate into the fractures in the country rocks of granite bodies. The mafic dikes generally occurred within the corresponding mafic volcanic belt that was located on the west of the intermediated-acid eruption belt of the same time, indicating that the mafic magma of eruption and intrusion should have been derived from the same source. Both reducing scales of the intermediated-acid eruption and the seaward migration of mafic eruption and intrusion belts after the Late Jurassic suggest decreasing crustal temperature of this area in the Late Mesozoic.