走滑拉分作用与相山产铀火山盆地的就位

Strike-slip pull-apart process and emplacement of Xiangshan uranium-producing volcanic basin

相山火山盆地是我国著名的产铀火山盆地。本文依据相山盆地深部地质研究成果以及大陆动力学理论 ,探讨了相山产铀火山盆地的就位机制。研究表明 ,相山火山盆地火山活动划分为两个旋回 ,其就位受制于区域深断裂的走滑拉分作用。即第一旋回的火山机构就位于NE向深断裂右旋走滑复活产生的EW向拉分构造 ,形成了东西向展布的裂隙式火山喷溢带 ;第二旋回的火山机构就位于NE向深断裂左旋走滑复活产生的SN向拉分构造与EW向基底断裂的结点 ,产生了中心式火山岩浆喷溢侵出。此外 。

Xiangshan volcanic basin is one of the famous uranium producing volcanic basins in China. In this paper, emplacement mechanism of Xiangshan uranium producing volcanic basin is discussed on the basis of the latest research achievements of deep geology in Xiangshan area and the theory of continental dynamics. The study shows that volcanic activity in Xiangshan volcanic basin may be divided into two cycles, and its emplacement is controlled by strike slip pull apart process originated from the deep regional faults. Volcanic apparatus in the first cycle was emplaced in EW trending structure activated by clockwise strike slipping of NE trending deep fault, forming the EW trending fissure type volcanic effusion belt. Volcanic apparatus in the second cycle was emplaced at junction points of SN trending pull apart structure activated by sinistral strike slipping of NE trending deep faults and EW trending basement faults causing the center type volcanic magma effusion and extrusion. Moreover, the formation mechanism of large rich uranium deposits is discussed in this paper as well.