华南大陆边缘新生代构造地貌演化机制研究

研究表明,从中生代安第斯型大陆边缘发展到现代弧盆体系,华南大陆边缘的地貌演化经历了中生代末期的古华夏山脉、新生代早期的准平原和中新世以来的海盆三个阶段。古华夏山脉的夷平导致本区陆壳减薄、莫霍面埋深变浅和区域性的重力升高;而地壳温度的整体下降则导致中生代壳内岩浆层自上而下的固结和盖层断裂的向下延伸。两者的耦合最终导致陆缘地区从中新世起发生大规模的断块沉陷,其结果是古准平原面下降到海面之下、海区正断层体系形成、地幔岩浆大量溢出、莫霍面位置被压低、沉降区两侧地块被顶托隆起并形成岛弧和断块山。

Mechanism of the Cenozoic tecto-geomorphologic evolution in the Southeast China continental margin

From the Mesozoic Andean continental margin to the present-day arc-basin system,the evolution of landform of Southeast China continental margin underwent three stages,i.e.,Palaeocathysian mountains at the end of the Cretaceous,peneplain in the late Paleogene,and sea-basins in the Neogene.Leveling of the Palaeocathysian mountains reduced the crustal thickness and thus decreased the imbedding depths of the Moho and increased the bouguer gravity.On the other hand,descending crustal temperature resulted in both...