基于GIS的证据权法在浙西铜矿资源成矿预测中的应用

Application of GIS-based weights of evidence method in metallogenic prediction of copper resources in western Zhejiang

浙江西部地区构造与岩浆活动频繁,区内分布有元古宙和古生代的铜矿成矿有利层位,北东向为主的深大断裂发育且多次活动,神功期和燕山早期的岩浆活动与成矿关系较密切。长期而复杂的地质演化、构造作用和岩浆活动为区内许多矿产的形成提供了良好的条件,铜、金、银等矿产的成矿条件较好。在分析研究区构造、地层、岩石、断裂等特点并在对浙江西部铜矿床的成矿规律深入研究的基础上,利用MapGIS 6.7和MORPAS 3.0软件平台提取构置了来自地质异常、成矿异常等多源信息的多个地质变量信息,将研究区划分为5 km×5 km的网格单元共1 755个,利用证据权法的数学模型对研究区铜矿资源进行预测,最终圈定了5个成矿远景区作为今后工作的重点区域。

In the western region of Zhejiang Province,tectonic and magma activities occurred frequently,and favorable layers for copper resource in Proterozoic era and Paleozoic era were distributed there,deep fractures of NE strike were developed and active,magma activities Shengong period and the early stage of Yanshan magma activity was relative to mineralization. The long-term and complexed geological evolution,tectonic and magmatic activities provided well metallogenic conditions for Au,Ag and Cu minerals in the study area. Based on analyses of structure,strata,rocks,fractures and minerogenetic regular patterns in the western region of Zhejiang and with the help of MapGIS 6. 7 and MORPAS 3. 0 soft wares,the multi-source information of geological anomaly,mineralization abnormalities and geological variables were obtained. The study area was divided into 1 755 units with a range of 5 km × 5 km for each unit.The potential value of copper resource was calculated by weights of evidence model and five metallogenic prospects were obtained.