摘要
为研究包古图斑岩铜矿的矿床模型,文章引入基于特征光谱的矿物组分快速提取方法对岩芯样品的光谱进行蚀变矿物含量提取。该方法是将光谱曲线每个吸收峰近似为三角形,提取三顶点数值(波长与反射率)。假设每个顶点反射率为纯矿物光谱的线性叠加,结合含量来建立等式。以美国地质调查局矿物光谱库光谱为端元光谱。通过解方程组获取矿物组分。将提取出的钾化、石英—绢云母化和青磐岩化三种蚀变生成柱状图,结合实地测量的铜元素含量柱状图进行对比分析,总结出包古图斑岩铜矿垂向上的蚀变分带规律和铜矿化的分布规律。基于特征光谱的矿物组分快速提取方法可有效提取感兴趣的蚀变矿物,在矿床研究中具广泛应用前景。
To investigate the deposit model of Baogutu porphyry copper deposit,mineral instant identification method based on characteristics absorption features is applied to extract alteration mineral abundances from spectra of borehole samples in study area.By this method,each absorption wavelength has been simplified to a triangle（left,right shoulder and absorption peak）.Vertexes coordinates（wavelength and reflectance）of these triangles have been extracted.There is an assumption that reflectance of each vertex is a linear combination of spectra of pure minerals at relative wavelength.Thus,equations between extracted reflectance and spectra of end-members and relative abundances can be established.Mineral contents can be obtained by solving equations.Abundances of three kinds of alteration minerals（potassic alteration,quartz-sericite-alteration,and propylitic-alteration）have been chosen to draw histograms compared with histograms of in situ measured copper contents.Vertical distribution laws of alteration minerals and copper were summarized via these histograms.So this mineral identification method is an effective tool to extract alternation minerals and can be widely used in deposits research.
出处
《有色金属（选矿部分）》
CAS
北大核心
2012年第5期6-11,20,共7页
Nonferrous Metals（Mineral Processing Section）
基金
中国地质调查局项目(1212011120340)
国家自然科学基金资助(41001266)
关键词
特征光谱
矿物组分
斑岩铜矿
蚀变分带
characteristic spectrum
mineral composition
porphyry copper deposit
alteration zoning
