基于地质与重磁数据集成的河北迁安铁矿集区三维成矿预测

3D Metallogenic Prediction Based on Geological and Gravity-magnetic Data Integration in the Qian'an Iron Ore Concentration Area, Hebei Province

河北迁安铁矿矿集区是我国典型的早前寒武纪条带状铁矿富集区和重要的铁矿石原料基地,近年来其保有资源量不断下降,急需开展深部资源找矿工作。基于地质与重磁数据等多源信息融合开展地质理论指导下的三维地质建模是当前深部矿产资源勘查与评价的重要途径和研究热点。本文以迁安铁矿集区为研究对象,基于地质与重磁数据资料综合解译,建立了1:5万迁安幅三维地质结构模型;在此基础上,以区域成矿理论和找矿勘查模型为指导,总结沉积-变质型铁矿的控矿要素,建立了综合信息定量预测模型;进一步应用"立方体预测模型"提取成矿有利信息,依据信息量值,圈定了5个找矿远景区。研究表明,重磁异常能够有效推断矿集区内断裂构造分布和含铁建造,为区域性三维地质模型的建立提供支撑;同时将传统的二维综合信息成矿预测方法拓展到三维空间,预测结果为该区深部及外围找矿工作提供参考。

The Qian’an iron ore concentration area is a typical Precambrian BIF enrichment area and also an important raw material base for iron ore.In recent years,the proven reserves have been declining continuously,so it is urgent to carry out deep iron resources prospecting work.3D geological modeling based on geological and gravity-magnetic data integration,under the guidance of geological theory,is an important method and frontier of mineral resources exploration and assessment in the world.The Qian’an iron ore concentration area was taken as the study area.Based on geological and gravity-magnetic interpretation data,the authors established 3D geological model of Qian’an geological map(1:50 000)and then,guided by regional metallogenic theory and prospecting model,the authors summed up some favorable geological conditions for ore control,and established the quantitative prediction model.By using“cubic predicting model”prospecting method,the authors delineated 5 predicted targets according to the value of prospecting information.The research results show that the gravity and magnetic anomalies can effectively infer fault structures and iron-bearing formations distribution in the ore-concentrating area,which provides support for regional 3D geological modeling.Meanwhile,this research extends the traditional metallogenic prediction method to 3D space,which can provide reference for prospecting work in the deep and peripheral areas.