矿物定量分析实验用捷克 FEI 公司生产的 MLA650F 型矿物解离分析仪，采用 MLA 原样法 和 MLA 重矿法分别对毛乌素沙地西南和东南地区典型沙样的矿物组成以及含量进行分析，结果表 明：MLA650F 仪器测量结果的重复性好，精确度高，测得的矿物种类比光学显微镜更丰富，但不能 如同光学显微镜一样直接提供矿物最原始的颜色、形状、透明度、光泽、表面断口等特征。虽然扫 描电镜与光学显微镜测得的单个矿物含量和矿物分析指标存在一定差异，但矿物含量变化趋势基 本一致，均得到毛乌素沙地主要轻矿物以石英-长石为主，重矿物以角闪石-石榴子石为主的结 论。此外，扫描电镜与光学显微镜对同一样品的矿物分析指标变化趋势基本一致，其中 MLA 原样 法与光学显微镜的 Q/TF 和 ATi 指标同化学风化指标 CIA 结果一致，均表明毛乌素沙地西南地区风 化作用较东南地区强。虽然扫描电镜与光学显微镜均能反应沉积物的沉积环境，但在实际工作 中，要注意所使用的数据应建立在同一测量系统内，不同实验室或实验方法测得的实验数据在引 用时要慎重。
The quantitative analysis of mineral experiments with Czech FEI company MLA650F mineral liberation analyzer, use the MLA original sample method and MLA heavy mineral method to analyze the mineral composition in the southwest and southeast of Mu Us Sandy Land in Shaanxi Province and Inner Mongolia Autonomous Region, China. Results show that MLA650F have good repeatability and high accuracy, and the mineral types measured are richer than those measured using the optical microscope. However, unlike the optical microscope, it cannot directly provide the original color, shape, transparency, luster, surface fracture, and other characteristics of the mineral. Although the individual mineral content and the mineral analysis index measured by QEMSCAN and optical microscope have some differences, the mineral change trend is basically the same. It is concluded that the main light minerals in Mu Us Sandy Land are quartz-feldspar and the heavy minerals are hornblende-garnet. In addition, QEMSCAN and optical microscope show similar change trend of mineral analysis indexes of the same sample. The original sample method of MLA is consistent with the Q/TF and ATi indexes of the optical microscope and with the CIA indexes of chemical weathering. Results showed that the weathering in the southwest of Mu Us Sandy Land was stronger than that in the southeast. Although both QEMSCAN and optical microscope can reflect the sedimentary environment, in practice, it should be noted that the data used should be established in the same measurement system, and the experimental data measured by different laboratories or experimental methods should be carefully quoted.
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