安徽拂晓地区地物化特征及找矿意义

Geophysical and Geochemical Characteristics of the Fuxiao Area,Anhui Province and Their Prospecting Significance

拂晓地区位于苏鲁超高压变质带安徽段的张八岭地区,地质构造条件与山东段的胶东金矿矿集区类似,具有较好的成矿地质条件和找矿前景。为探索拂晓地区金矿找矿前景,本次研究系统开展地物化工作,以面积性的磁法、化探异常为依据,圈定隐伏岩体范围,提供多目标的直接找矿信息,减小找矿范围,预测出两个重点找矿远景区。在重点找矿远景区内,部署了两条可控源音频大地电磁和频谱激电剖面对重点区域的深部纵向结构特征进行探索。综合研究拂晓地区的地物化资料,提出以“弱磁异常-化探异常中心-中等强度的电性异常”为特征的物化探找矿标志;“煌斑岩脉-闪长质脉岩”为特征的地质直接找矿标志;“次级断裂带-不同岩体间的接触带区域”为重点找矿区域的地物化综合找矿方法,有效增强了找矿能力。本研究可为安徽拂晓地区及其邻区的矿产勘查工作提供一定的指示。

The Fuxiao area is located in the Zhangbaling region of the Anhui section of the Sulu UHP metamorphic belt,where geological conditions are similar to those of the Jiaodong gold deposit in the Shandong section,showing good ore-forming geological conditions and ore-search prospect.To further reveal the gold ore prospecting potential,a systematic geophysical and geochemical survey has been conduced in this area.Based on areal magnetic and geochemical anomalies,the range of concealed rock bodies was delineated,providing multi-target direct prospecting information and reducing the prospecting scope.Two key prospecting areas were predicted,where two electrical profiles were deployed to explore the longitudinal structural features at depth.Integrating geological,geophysical and geochemical data,it is suggested that“weak magnetic anomalies-centers of geochemical anomalies-medium intensity electrical anomalies”should be ore-search marks,while“lamprophyre veins-diorites veins”are a direct sign for prospecting,and the“secondary fault zones-contact zones between different rock masses”are the target sites for further geophysical and geochemical surveys.These results would permit to effectively enhance the prospecting ability and shed light on the mineral exploration in the Fuxiao area of Anhui and neighboring regions.