在内蒙古草原拜仁达坝矿区上部的地表覆盖层中均匀采集土壤样品, 用X射线衍射和近红外光谱技术对样品进行分析测试, 旨在探讨草原矿区土壤成分来源及其与地下岩体的关系。结果表明, 该土壤样品主要由石英、 石墨、 碳酸盐、 角闪石、 云母、 绿泥石、 蒙脱石、 伊利石、 块磷铝矿、 硬水铝石、 蓝铜矿、 赤铁矿等组成, 说明了地表土壤成分不仅来源于地表岩体风化产物, 与地下岩体及其围岩蚀变作用更加密切相关。土壤中所含蓝铜矿和赤铁矿主要来源于矿体氧化带, 可作为找矿标志; 蚀变矿物组合主要为绿泥石-伊利石-蒙脱石, 推测该区域大致经历了钾化→硅化、 碳酸盐化→绢云英岩化→泥化的蚀变过程。通过分析蚀变矿物组合, 可以还原围岩蚀变及物理风化过程, 为深部找矿以及矿床成因研究提供了重要的参考信息, 提高了找矿的成功率。X射线衍射和近红外光谱技术用于矿物、 矿床研究方面, 有着经济、 快速的特点, 能很好的鉴定矿区地表土壤中的矿物成分。尤其是近红外光谱分析技术对样品要求低, 可以对样品进行快速批量的分析, 具有其独特的优越性。随着近红外技术的发展, 其在地质领域中将有越来越广泛的应用, 并且能在找矿勘探中发挥重要的作用。

The soil samples uniformly overlying the Bairendaba deposit of the Inner Mongolia grassland were collected, and analyzed with X-ray diffraction (XRD) and near infrared spectrum (NIR), for exploring the origins of the soil from the grassland mining area and the relationship with the underground rock. The results show that the samples consist of quartz, graphite, carbonate, hornblende, mica, chlorite, montmorillonite, illite, berlinite, diaspore, azurite, hematite, etc. These indicate that the soil samples were not only from the weathering products of the surface rock, but also from the underground rock mass and the alteration of the wall rock. The azurite and the hematite contained in the soil, mainly coming from the oxidation zone of the ore-bodies, can be used as the prospecting marks. The alteration mineral assemblage is mainly chlorite-illite-montmorillonite and it experienced the alteration process of potassic alteration→silicification→carbonatization→silk greisenization→clayization. Also, the wall rock alteration and the physical weathering processes can be accurately restored by analyzing the combination of the alteration minerals, which can provide important reference information for the deep ore prospecting and the ore deposit genesis study, improving the rate of the prospecting. The XRD and NIR with the characteristics of the economy and quickness can be used for the identification of mineral composition of soil, and in the study of mineral and mineral deposits. Especially, NIR has its unique superiority, that is, its sample request is low, and it can analyze a batch of samples quickly. With the development of INR, it will be more and more widely applied in geological field, and can play an important role in the ore exploration.