Mineralogical and compositional characteristics of Late Permian coals from an area of high lung cancer rate in Xuan Wei, Yunnan, China: Occurrence and origin of quartz and chamosite
Mineralogical and compositional characteristics of Late Permian coals from an area of high lung cancer rate in Xuan Wei, Yunnan, China: Occurrence and origin of quartz and chamosite
复制标题
DOI：
10.1016/j.coal.2008.09.001
复制
发表时间：
2008-12-01
影响因子：
5.6
通讯作者：
Ren, Deyi
中科院分区：
文献类型：
--
作者：
Dai, Shifeng;Tian, Linwei;Ren, Deyi
云南省宣威县部分乡镇是我国肺癌死亡率最高的地区之一，该地区的流行病通常被归因于家庭燃煤释放的多环芳烃（PAHs）。然而，引起癌症的罪魁祸首并不确定为Tian [Tian，L，2005.中国宣威燃煤排放与肺癌。博士论文，加州大学伯克利分校。]在这些煤、煤烟排放物和肺癌组织中发现了纳米石英。本文对宣威煤进行了矿物学和地球化学研究，旨在揭示与肺癌流行有关的矿物。本文采用光学显微镜、低温灰化、X射线衍射分析、扫描电子显微镜和能谱仪、电感耦合等离子体质谱等方法，对宣威两个矿区煤中矿物和元素的丰度、赋存状态和来源进行了研究。煤中的矿物主要由石英、高岭石、高岭石和方解石组成。石英粒度较小，多小于20目，属自生石英。菱沸石主要以细胞填充物的形式出现。石英和高岭石的产出表明它们来自热液流体。后生方解石来源于含钙流体。高岭石主要来源于煤盆地西部的康滇古陆沉积物源区。宣威煤的化学成分中SiO2、Fe2O3、TiO2、CaO、MnO、V、Co、Ni、Cu、Zn含量较高。高SiO_2含量主要来源于石英，高Fe_2O_3含量主要来源于绿泥石。煤中Mn含量高、Mg含量低，表明有热液输入。CaO主要赋存于后生方解石中。元素Ti、Co、Ni、Cu、Zn和稀土元素来源于源区玄武岩。(c)2008 Elsevier B.V.保留所有权利。
Some townships in Xuan Wei County, Yunnan Province, have one of the highest lung cancer mortality rates in China and the epidemic disease in the area has generally been attributed to the polycyclic aromatic hydrocarbons (PAHs) released from domestic coal burning. However, the cancer-causing culprit is not settled as Tian [Tian, L, 2005. Coal Combustion Emissions and Lung Cancer in Xuan Wei, China. Ph.D. thesis, University of California, Berkeley.] found nanometer quartz in these coals, soot emissions, and lung cancer tissues. We have conducted mineralogical and geochemical studies of the coals from Xuan Wei for the purpose of shedding light on the minerals which may be related to the epidemic lung cancer. In this paper, abundances, modes of occurrence, and origins of minerals and elements in the coals from two mines in Xuan Wei have been studied using optical microscope, low-temperature ashing, X-ray diffraction analysis, scanning electron microscope equipped with energy-dispersive X-ray spectrometer, and inductively-coupled plasma mass spectrometry. The minerals in the coals are mainly composed of quartz, chamosite, kaolinite, and calcite. The particle size of quartz is rather small, mostly less than 20 pin and it is of authigenic origin. Chamosite occurs mainly as cell-fillings. The occurrence of quartz and chamosite indicates that they were derived from the hydrothermal fluids. Epigenetic calcite is derived from calcic fluids. Kaolinite is derived mainly from sediment source region of Kangdian Oldland to the west of coal basin. The composition of Xuan Wei coal is high in SiO2, Fe2O3, TiO2, CaO, MnO, V, Co, Ni, Cu, and Zn. The high SiO2 content is attributed to quartz, and the Fe2O3 content to chamosite. The high Mn and low Mg contents in the coal indicate the inputs of hydrothermal fluids. CaO occurs mainly in epigenetic calcite. Elements Ti, Co, Ni, Cu, Zn, and rare earth elements were derived from the basaltic rocks at sediment source region. (c) 2008 Elsevier B.V. All rights reserved.