南雄断裂构造剥离作用及其与铀成矿的关系

南雄断裂带下盘发育规模较大，平行于断裂走向的糜棱岩带，上盘为一中新生代盆地，随着地层时代的变新，沉积中心向断层一侧迁移。本文通过对断裂下盘糜棱岩带的剖面测量，对糜校岩中Ｓ－Ｃ面理、旋转碎斑和拉伸线理等各种韧性变形组构的详细研究，根据变形组构的运动学指向，结合断裂带内脆性构造岩及盆地中正断层的发育状况和展布特征，确定南雄断裂为一规模巨大的剥离断层。对剥离断层与铀成矿的关系本文也进行了初步探讨。

TECTONO-DENUDATIONAL PROCESS OF NANXIONG FAULT AND ITS RELATIONS TO URANIUM METALLOGENESIS

A large mylonite zone is distributed on the footwall of Nanxiong fault,which is parallelto the fault. On the hanging wall,there is a Meso-Cenozoic basin. As sedimentation centersare moved towards the side of the fault,the strata become more younger. By investigation ofthe mylonite zone along the profile on the footwall of the fault,the author studies in detailvarious kinds of ductile deformation fabrics in mylonites such as S--C fabrics,rotational porphyroclasts and stretching lineations etc. In the light of the kinematic direction of deformational fabrics,together with the characteristics of brittle tectonites in the fault and the distribution of normal faults in the basin,the author believes that Nanxiong fault is a big--size denudational fault. According to the formation and evolution of the denudational fault,its rockand ore-controlling roles,the relations between the fault and uranium metallogenesis are alsopreliminarily discussed.