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通常认为中国东南大陆中生代时地壳裂解作用发生在燕山晚期。对赣南地区广泛分布的双峰式火山岩和A型花岗岩进行了Rb -Sr同位素定年研究 ,确定基性端元玄武岩的Rb -Sr等时线年龄为 170～ 180Ma ,酸性端员流纹岩和A型花岗岩的Rb -Sr等时线年龄为 160～ 180Ma ,表明它们形成于中侏罗世早期。由此提出东南大陆中生代时最早的裂解作用应该始于燕山早期。
It is generally believed that the crustal lysis during the Mesozoic in the southeastern China occurred in the late Yanshan period. The Rb-Sr isotope dating of widely distributed bimodal and A-type granites in southern Jiangxi Province was studied. The Rb-Sr isochron age of the basic terminal basalts is 170-180 Ma, The A-type granites have an Rb-Sr isochron age of 160-180 Ma, indicating that they were formed in the early Middle Jurassic. It is suggested that the earliest lysis of Mesozoic in the southeast China should begin with the early Yanshanian.