Clay minerals are fine-grained material, which become pliable when they interact with water. The minerals comprise silica, alumina, water and also iron, alkalis and alkaline earth elements. There are several ways of formation of clay minerals: (i) Aqueous alternation, (ii) Authigenesis, (iii) Diagenesis, (iv) Terrestrial weathering, and (v) Biomediated clay mineralization. These processes drive chemical composition and properties of the clay minerals. Depending upon their chemical and physical properties, clay minerals can be applied to different areas such as geology, water science, soil science, geotechnical engineering, geomorphology, seismology, astrobiology and atmospheric science.
Due to the high surface charges originating from isomorphous substitution in the crystal lattice, and from the presence of pH dependent surface edges or broken bond sites, clay minerals can absorb positively charged ions and organic components on their surface. Some chemical elements in clay minerals can be potential sources of nutrients for bacteria. Clay mineral-bacteria interaction can play a major role in formation of new minerals. Such properties of clay minerals can also be used in some internal and external medical treatment. Clay minerals are also good indicators for the study of past climatic conditions and sea level changes.
Dr Elshan Abdullayev is a geoscience programme coordinator at French-Azerbaijani University (UFAZ). He completed his Ph.D at Leipzig University (Germany) in 2015. After his PhD, Elshan started work as a researcher at Institute of Geography, Azerbaijan National Academy of Science. Elshan has done his post-doc at Mugla Sitki Kochman University (Turkey) between 2016-2017. He was DAAD fellow at University of Greifswald (Germany) in 2018 and Institute of Advanced Study fellow at Durham University (UK) in 2019. Elshan was appointed as a geoscience programme coordinator at UFAZ in 2019. He studies clay minerals and geochemical composition of the sediments and also application of clay minerals in water treatment.