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江西广丰－上饶地区沿江绍断裂带和信江断裂带展布有一系列ＮＥ－ＮＥＥ走向的白垩系断陷盆地，在断陷盆地沉积的同时发育了大面积分布的白垩系玄武岩，这套玄武岩被划分为与盆地演化阶段有关的两个喷发亚旋回，即早期的茅店亚旋回和中晚期的塘边亚旋回，分属拉斑玄武岩系列和钾玄岩系列。前者喷发于陆相陆上环境，相对低钾、轻稀土及地幔不相容元素，具接近原始幔源岩浆的Ｓｍ－Ｎｄ、Ｒｂ－Ｓｒ同位素组成，岩浆来源深度较浅（５６ｋｍ），经历了以橄榄石为主的镁铁矿物的分离结晶作用。后者喷发于陆相水下环境，富钾、轻稀土及地幔不相容元素，具壳幔混源的Ｓｍ－Ｎｄ、Ｒｂ－Ｓｒ同位素组成，岩浆来源较深（８３ｋｍ），在莫霍面附近混染了壳源物质。这两类玄武岩在成因上的上述差异，主要受控于盆地下应力状态及裂谷深度的变化。
A series of NE-NEE strike-slip Cretaceous rift basins are distributed along the Jiangshao-Shangrao areas along the Jiangshao-Shahe fault zone and the Xinjiang fault zone. Cretaceous basalts with large area are developed at the same time as the sedimentary basins It is divided into two eruption sub-cycles related to the evolution stage of the basin, namely, the Early Mao Sub-Cyclone and the Late Tangbian Sub-Cyclone, belonging to the series of tholeiite basalts and potassium basalts. The former erupted in the terrestrial environment, relatively low potassium, light rare earth and mantle incompatible elements, with the close to the original mantle magma Sm-Nd, Rb-Sr isotopic composition, shallow magma source depth (56km), experienced Olivine-based mafic mineral separation and crystallization. The latter is erupted in the marine facies environment and is rich in potassium, light rare earth and mantle incompatible elements, with the crust-mantle mixed source Sm-Nd and Rb-Sr isotopes. The magma source is deep (83km) Dyed shell material. The above differences in the genetic causes of these two types of basalts are mainly controlled by the changes in the underlying stress state and rift depth in the basin.