Higher Institute of Water Sciences and Techniques of Gabès (ISSTEG), University of Gabès, Gabès, Tunisia.
Research Laboratory Geo-Systems, Geo-Resources, Geo-Environment (LR3G), Department of Geology, Faculty of Sciences of Gabès, University of Gabès, City Campus Erriadh-Zrig, 6072, Gabès, Tunisia.
Environ Monit Assess. 2024 Mar 26;196(4):398. doi: 10.1007/s10661-024-12523-3.
The current study was conducted within the context of the Holocene era in Sebkha El-Guettiate, located in southeastern Tunisia. The aim was to determine the factors influencing the geochemical and mineralogical composition of sediments and to elucidate the sedimentary characteristics of the Holocene within the Sebkha core. We examined a sediment core extending 100 cm from this Sebkha, subjecting it to comprehensive analysis to uncover its sedimentological, mineralogical, and geochemical properties. Several techniques were employed to strengthen and validate the connections between geochemical and mineralogical analyses, including X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and infrared (IR) spectroscopy, among others. Furthermore, statistical analyses utilizing principal component analysis (PCA) were applied to the results of the geochemical and mineralogical studies, aiding in the identification of patterns and relationships. A comprehensive mineralogical assessment of the core's sediments revealed the presence and interpretation of carbonate minerals, evaporite minerals, and detrital minerals. Through the application of infrared (IR) spectrometer techniques to all sediment samples, we gained insight into the mineralogical components and the distribution of key elements such as quartz, kaolinite, calcite, feldspar, and organic carbon. The geochemical composition demonstrated a clear dominance of silica (SiO2), accompanied by fluctuations in carbonate percentages (CaCO3). The prominent major elements, primarily magnesium (Mg) and calcium (Ca) originating from dolomitization, sodium (Na) and chlorine (Cl) from halite, and calcium (Ca) from gypsum, exhibited varying levels. Results from Rock-Eval 6 pyrolysis indicated that the organic matter within the sediments is generally a mixture of terrestrial and aquatic origins. This study provides practical information that underscores the diverse origins contributing to Sebkha sediment formation, often influenced by saline systems.
本研究在突尼斯东南部 Sebkha El-Guettiate 的全新世背景下进行。目的是确定影响沉积物地球化学和矿物组成的因素，并阐明 Sebkha 岩芯内全新世的沉积特征。我们对来自该 Sebkha 的 100 厘米长的沉积岩芯进行了综合分析，以揭示其沉积学、矿物学和地球化学性质。采用了多种技术来加强和验证地球化学和矿物学分析之间的联系，包括 X 射线衍射（XRD）、X 射线荧光（XRF）、扫描电子显微镜（SEM）和红外（IR）光谱等。此外，还应用了主成分分析（PCA）等统计分析方法对地球化学和矿物学研究的结果进行分析，以帮助识别模式和关系。对岩芯沉积物的全面矿物学评估揭示了碳酸盐矿物、蒸发盐矿物和碎屑矿物的存在和解释。通过对所有沉积物样品应用红外（IR）光谱仪技术，我们深入了解了矿物成分和关键元素（如石英、高岭石、方解石、长石和有机碳）的分布。地球化学组成显示出明显的硅（SiO2）优势，同时碳酸盐百分比（CaCO3）波动。主要元素（Mg 和 Ca 源自白云石化，Na 和 Cl 源自石盐，Ca 源自石膏）的含量也有所不同。Rock-Eval 6 热解分析结果表明，沉积物中的有机质通常是陆地和水生来源的混合物。本研究提供了实用信息，强调了多种来源对 Sebkha 沉积物形成的贡献，这些贡献通常受到盐水系统的影响。
