昆明地区碳酸盐岩发育红土载磁矿物的提取与鉴定

Extraction and Identification of Magnetic Carrier Minerals in Red Soil Derived from Carbonate Rock in Kunming

利用重液分离工艺对昆明地区磁化率最高的碳酸盐岩发育的红土进行载磁矿物的分离提取,并对提取出的样品进行X射线衍射(XRD)鉴定,结果显示碳酸盐岩发育红土的主要载磁矿物为磁赤铁矿(γ-Fe_(2)O_(3))、赤铁矿(α-Fe_(2)O_(3))和针铁矿(α-FeOOH),它们占总载磁矿物的半定量比例分别为30%、37%和33%,这些测定结果大体上与传统的磁学参数测定方法推测的结果吻合,但在准确鉴定、识别和半定量分析上明显优于前者。

The magnetic carrier minerals were separated by heavy liquid from the red soil in Kunming derived from carbonate rock and with the highest magnetic susceptibility,and then identified by the method of X-ray diffraction(XRD).The results showed that the main magnetic carrier minerals were maghemite(γ-Fe_(2)O_(3)),hematite(α-Fe_(2)O_(3))and goethite(α-FeOOH)and their semi-quantitative proportions were accounted for 30%,37%and 33%of total magnetic carrier minerals respectively,which were generally in agreement with those inferred by traditional magnetic parameter determination method,but superior to the latter in terms of identification accuracy and semi-quantitative analysis.