摘要
新疆于田塔木其铜锌矿是西昆仑造山带内众多与火山作用有关的热水喷流沉积块状硫化物矿床之一,但该矿的空间位态与典型层控矿床不一致。研究区经历的主要构造运动期次可分为3期,S2期构造运动对现今岩石及矿体的空间分布状态起决定性作用。野外及镜下详细观察表明,S2期构造变形为强压应力兼具一定剪切性质的脆韧性变形,对研究区内原始层理及矿体进行了构造置换。S2期构造透镜体长轴及劈理产状统计表明,构造透镜体空间展布状态小受S2期劈理控制,透镜体最大压扁面平行于S2期劈理面分布,研究区在S2期遭受了强烈的南北挤压应力。通过对小型褶皱、透镜体的观测及劈理的统计,结合构造剖面的测制,推测矿体上一级构造样式为大型无根褶皱,矿体本身为加厚的Z型次级褶皱形成的透镜体,矿体所处部位可能为无根褶皱的背形南翼或向形北翼。S3期节理产状要素统计表明,在S3期研究区发生了南北挤压应力作用下的脆性破裂,这些破裂对矿体的分布有一定影响。
The Tamuqi copper zinc ore deposit in Yutian county,Xinjiang is one of the sedimentary massive sulfide deposits in west Kunlun orogenic belt which was related with volcano exhalation,but its spatial state is not consistent with typical stratabound deposits. The major tectonic movements can be divided into 3 stages,and the S2 stage movement plays a decisive role on the rock and orebody spatial distribution. Field investigation and microscopic observations show that the S2 structural deformation level is brittle-ductile deformation formed by strong compressive and shear stress. The S2 tectonic lens axis and the occurrence of the cleavage statistics shows the distribution of tectonic lens is parallel to the S2 cleavage,and the study area in the phase S2suffered a strong north-south compressive stress. Through statistical analysis and observations of cleavage and folds,structural lens,combined with structural profile,we speculate that the higher tectonic style of the orebody is rootless fold. Orebody itself as Z-type secondary fold formed thick tectonic lens,and located in limb of higher fold. Statistics of S3 joint occurrence show that the S3 brittle fracture in study area formed by south-north compressive stress.
出处
《地质与勘探》
CAS
CSCD
北大核心
2014年第2期360-368,共9页
Geology and Exploration
关键词
构造控矿
多期变形
构造置换
塔木其
structural control of mineralization,multiple deformations,structural transposition,Tamuqi
