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岩石学及同位素地质学研究均表明，含榴辉岩的胶南地块在高温高压变质后经历过快速降压过程，这一过程在构造上表现为隆升－伸展构造。这种构造在胶南地块有两种形式：其一为地块内部的垂向缩短、水平向伸展构造，以浅色脉体的变形为特征，并反映出从深层次向浅层次的转化；另一为地块边部的正滑型构造带，可分为早期塑性变形和叠加于其上的且分布于地块外侧的晚期脆性－半脆性变形。反映运动矢量的拉伸线理走向呈放射状：北段走向近南北，中西段近东西。这是地块北西侧的变形特点，东南侧情况不明。北部正滑型剪切带中白云母40Ar／39Ar坪年龄表明，伸展构造的时代为146Ma±。这次构造运动可能由俯冲至上地幔的大洋板块与地壳拆离造成的重力均衡所引起，其结果不仅使得大陆地壳上隆，而且还使榴辉岩从下地壳上升至地表。
Both petrology and isotopic geology have shown that the Jiaonan block containing eclogites experienced a rapid step-down process after high-temperature and high-pressure metamorphism. This process is characterized by uplifted-extensional structures. This kind of structure has two forms in the Jiaonan block: one is the vertical shortening and the horizontal extension structure within the block, which is characterized by the deformation of the light veins and reflects the transformation from deep to shallow level; The other is the positive slippery tectonic belt at the edge of the block. It can be divided into early plastic deformation and late brittle-semi-brittle deformation superimposed on the outside of the block. The stretching lineage that reflects the motion vector is radial: the north section goes near north and south and the middle and west sections close to east and west. This is a deformation feature on the north west side of the block, with unknown conditions on the southeast. The age of 40Ar / 39Ar plateau of muscovites in the northern FWP shows that the age of extensional structure is 146Ma ±. This tectonic movement may be caused by the gravitational balance caused by the detachment of the oceanic plate from the subducting to the upper mantle and the crust. As a result, the tectonic movement not only makes the continental crust uplift but also raises the eclogite from the lower crust to the surface.