赣南龙潭金矿地质构造特征及形成机制分析

Analysis of Geological Structure Characteristics and Formation Mechanism of Longtan Gold Deposit in Southern Jiangxi

龙潭矿区金矿体空间赋存状态主要受区内SN向裂隙-断裂系统控制。通过对矿区裂隙-断裂穿插切割关系分析,认为区内SN向裂隙-断裂为加里东旋回陈公排倒转背斜伴生的2组交角很小的走向近SN的“X”型扭裂隙,在燕山期NE—NNE向构造应力的作用下,“X”型扭裂隙进一步扩大、贯通,成为矿区的容矿构造;区内EW向断裂形成于燕山早期,与NE—NNE向断裂交替发育,主要为成矿前期断裂;燕山晚期成矿作用结束,表现为强烈的断裂活动,生成一系列的NE—NNE向和EW向破坏性断裂构造。区内裂隙-断裂构造表现为具有多期次、压扭-张扭性特征。

The spatial occurrence state of gold ore body in Longtan mining area is mainly controlled by SN direction fracture-fault system in the area.Through the analysis of the fracture-fault interspersed cutting relationship in the mining area,it is considered that the SN direction fracture-fault in the area is two groups of X-type torsional fractures with small intersection angle and nearly SN direction associated with the Cale-donian cycle Chengongpai inverted anticline.Under the action of the NE-NNE direction tectonic stress in the Yanshan period,the X-type torsional fractures further expand and penetrate,becoming the ore-bearing structure of the mining area.The EW direction faults in the area were formed in the early Yanshan period and alternately developed with NE-NNE direction faults,mainly pre-mineralization faults.The late Yansha-nian mineralization ended,showing strong fault activity,generating a series of NE-NNE and EW direction destructive fault structures.The fracture-fault structure in the area is characteried by multi-stage,compres-sion-torsion-tension-torsion.