摘要
以"矿床成矿系列"理论为指导,利用"矿床模型综合地质信息预测"方法分析提取石墨典型矿床预测要素,结合典型矿床及石墨成矿地质特征提取区域预测要素,建立了区域成矿模式及区域预测模型。在陆缘海相对稳定的沉积环境下沉积形成的古元古代荆山群陡崖组徐村段含碳碎屑岩-有机质黏土岩-镁质碳酸盐岩建造、古元古代晚期区内的高角闪岩-麻粒岩相的中—高级变质作用是区内晶质石墨矿床形成的必要条件。区域性褶皱构造的翼部、次级褶皱构造的核部及转折端附近,角闪石、透闪石、透辉石、石墨、黑云母矿物组合特征是石墨矿床成矿、赋矿的重要要素,陡崖组徐村段石墨黑云斜长片麻岩或石墨透辉变粒岩是石墨矿床的重要找矿标志。石墨赋矿层位的高极化率、低电阻率、低磁异常特征是石墨矿床存在的重要指示标志。按照赋矿变质建造分布范围,控矿构造展布方向及区内电性、重磁异常特征等综合因素圈定预测区平面及深部延伸边界。全区圈定预测区85个,其中A级14个,B级11个,C级60个,分区域、地段、深度、级别(类别)定量估算500 m以浅资源量,预测晶质石墨矿物量1亿多t。
This work used the ＂metallogenic series of ore deposits＂ theory to extract the prediction factors of typical graphite deposits in Shandong Province with the method of ＂deposit model based on comprehensive geological information＂. With typical ore deposits and the geological characteristics of graphite deposits, we extracted the regional prediction factors and established regional metallogenic pat- tern and model. Those carbonaceous clastic rocks-organic clay rocks-magnesian carbonate formations of the Xucun Member, Douya Formation in the Paleoproterozoic Jingshan Group deposited in relatively stable epicontinental sea environment, and the middle-high metamorphism of the late Paleoproterozoie high amphibolites facies-granulite facies are necessary for the formation of the crystalline graphite deposits in this region. Near the wing of regional fold structures, the core and turning points of secondary folds, and the miner- al assemblage of amphibole, tremolite, diopside, graphite and biotite are important factors for the mineralization and ore hosting of these graphite deposits. The graphite biotite plagiogneiss or graphite diopside granulitite in the Xucun Member of Douya Formation is an important prospecting indicator of the graphite ore deposits. The high polarizability, low resistivity and low magnetic anomalies are im- portant indicators for the existence of graphite deposits. We delineated the planar distribution and deep-extending boundary based on the distribution of ore-hosting metamorphic formation, the extending range of ore-controlling structures and electrical, gravity and magnetic anomalies. A total of 85 prediction areas, including 14 A-class, 11 B-class, 60 C-class areas, were determined. We quantitatively estimated the resource amount shallower than 500 m based on region, section, depth and grade （category）, which amounts to more than 100 million tons in total.
出处
《地质学刊》
CAS
2016年第3期410-423,共14页
Journal of Geology
基金
国家地质勘查专项"全国矿产资源潜力动态评价--新兴矿种资源评价示范"(121201103000150003)
中国地质调查局地质矿产调查评价专项"全国重要矿种成矿区划部署研究"(12120114051501)
关键词
石墨矿
矿床模型综合地质信息
预测要素
预测区
山东西北地区
graphite ore deposit
deposit model based on comprehensive geological information
prediction factors
prediction areas
northwestern Shandong Province
