Hunegnaw Yirgalem, Getaneh Worash
Geological Institute of Ethiopia, P.O. Box 2302, Addis Ababa, Ethiopia.
School of Earth Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
Heliyon. 2024 Aug 14;10(16):e36132. doi: 10.1016/j.heliyon.2024.e36132. eCollection 2024 Aug 30.
The Abiyata Diatomite deposit is located in the Main Ethiopian Rift, which is characterized by strong extensional tectonics. The deposit is mostly made up of diatomaceous earth, which is a sedimentary rock made up of the fossilized remnants of diatoms, which are tiny algae. Diatomite's geological, geochemical, and mineralogical features, as well as its formation, are discussed in this research. To characterize diatomite from Abiyata, chemical, mineralogical, technological, and micro paleontological examinations were conducted on samples collected from outcrops and stream sections. The XRD characteristic peaks of diatomite demonstrate that it is primarily made up of Opal A silica, however certain crystalline phases were discovered in adequate amounts. Quartz and feldspar were the predominant crystalline phases, with lesser amounts of Calcite, Cristobalite, Illite, Mordinite, Wairakite, Halloysite, Clinoaptilolite, Adularia, and Tridymite. From SEM photomicrographs diatomites are primarily formed of benthic freshwater diatom species such as . Diatom species, sedimentary profile sections and mineralogical data suggest that diatomite was deposited in lacustrine-type freshwater shallow lake environment. Chemical data obtained from 10 diatomite samples show that while silica is the bodybuilding material for diatomite. i.e., Silica (SiO2), 76.9 %; Alumina (Al2O3), 3.49 %; Sodium Oxide (Na2O), 1.52 %; Potassium Oxide (K2O), 1.107 %; Iron Oxide (Fe2O3), 1.1 %; Loss on ignition (LOI) 13.7 and other oxides are below 1 %. Studies from technological properties like physical tests, chemistry, and mineralogy and micropaleontology of Abiyata diatomite suggest that calcined diatomite can be used for waste treatment processes in the filter aid industry and as filler material.
阿比亚塔硅藻土矿床位于埃塞俄比亚主裂谷，其特点是具有强烈的伸展构造。该矿床主要由硅藻土组成，硅藻土是一种沉积岩，由微小藻类硅藻的化石残骸构成。本研究讨论了硅藻土的地质、地球化学和矿物学特征及其形成过程。为了表征阿比亚塔的硅藻土，对从露头和溪流剖面采集的样本进行了化学、矿物学、工艺和微古生物学检查。硅藻土的XRD特征峰表明，它主要由蛋白石A二氧化硅组成，但也发现了一定数量的某些晶相。石英和长石是主要的晶相，方解石、方石英、伊利石、丝光沸石、歪长石、埃洛石、斜发沸石、冰长石和鳞石英的含量较少。从扫描电子显微镜照片来看，硅藻土主要由底栖淡水硅藻物种形成，如 。硅藻物种、沉积剖面和矿物学数据表明，硅藻土沉积于湖相淡水浅湖环境。从10个硅藻土样本获得的化学数据显示，虽然二氧化硅是硅藻土的主要成分。即二氧化硅（SiO₂），76.9%；氧化铝（Al₂O₃），3.49%；氧化钠（Na₂O），1.52%；氧化钾（K₂O），1.107%；氧化铁（Fe₂O₃），1.1%；烧失量（LOI）13.7%，其他氧化物含量低于1%。对阿比亚塔硅藻土的物理测试（如物理性质、化学、矿物学和微古生物学）等工艺特性研究表明，煅烧硅藻土可用于助滤剂行业的废物处理过程，并用作填充材料。
