Carbonate minerals are a major reservoir in the global carbon cycle and a key player in the sequestration and emission of atmospheric CO₂. In addition to the minerals’ frequent use in agriculture and construction, carbonate formation has been targeted for anthropogenic CO₂ sequestration. Due to carbonate’s importance in geological and anthropogenic realms, research on carbonate characterization and quantification is of interest. Here, we demonstrate a method to identify and quantify calcite (CaCO₃) and dolomite (CaMg(CO₃)₂) in sediment matrices using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Needing only a few minutes per sample, DRIFTS is a rapid technique that does not require hazardous chemicals and does not destroy samples during analysis. We selected the 2515 ± 9 cm⁻¹ absorbance bands for quantification as they exhibited little interference from sediment matrix minerals and large peak areas relative to other bands. The DRIFTS technique was compared to the traditional acidification headspace analysis method on artificial mixtures of sediment and carbonate as well as natural lake bed and river bank samples from the Upper Sangamon River Basin in Illinois, USA. DRIFTS offers an additional advantage over acidification in that it permits carbonate mineral identification simultaneously with its quantification. Though DRIFTS estimates were higher, a good correlation was found between DRIFTS and acidification estimates for both lake sediments (R² = 0.99) and bank samples (R² = 0.92), indicating DRIFTS is a reliable method for carbonate quantification in sediment matrices.

碳酸盐矿物是全球碳循环中的主要储层，并且是隔离和排放大气中CO _{2的关键因素}。除了这些矿物质在农业和建筑业中的频繁使用外，碳酸盐的形成还被人为地封存了CO ₂。由于碳酸盐在地质和人为领域中的重要性，因此有关碳酸盐表征和定量研究的研究备受关注。在这里，我们演示一种识别和定量方解石（CaCO ₃）和白云石（CaMg（CO ₃）₂使用漫反射红外傅里叶变换光谱仪（DRIFTS）在沉积物基质中测定）。每个样品仅需几分钟，DRIFTS是一种快速的技术，它不需要有害化学物质，并且在分析过程中不会破坏样品。我们选择2515±9 cm ^-1用于定量的吸光度谱带，因为它们几乎不受沉积物基质矿物的干扰，并且相对于其他谱带而言，峰面积较大。将DRIFTS技术与传统的酸化顶空分析方法进行了比较，该方法对美国伊利诺伊州上加蒙河流域的沉积物和碳酸盐的人工混合物以及天然湖床和河岸样品进行了分析。与酸化相比，DRIFTS具有另一个优势，因为它可以在定量分析的同时识别碳酸盐矿物。尽管DRIFTS估算值较高，但对于湖泊沉积物（R ²  = 0.99）和河岸样品（R ²），DRIFTS与酸化估算值之间存在良好的相关性。 = 0.92），表明DRIFTS是定量测定沉积物基质中碳酸盐的可靠方法。