lithologiaan

Lithologiaan refers to the study and description of rocks and their physical properties within geology. The term emphasizes observable characteristics such as rock type, texture, mineral content, grain size, color, porosity, permeability, and structure as they appear in outcrops, cores, or collected samples. Lithology provides the basis for describing, classifying, and mapping rocks and for interpreting their geological history. It deals with how rocks differ from one another in appearance and composition, while mineralogy, by contrast, focuses on the minerals themselves.

Rocks are commonly grouped into igneous, sedimentary, and metamorphic categories, but lithology adds finer detail by naming specific lithologies such as basalt, granite, sandstone, limestone, shale, quartzite, or schist. Descriptions often include texture (coarse- versus fine-grained), cementation, bedding or foliation, and weathering state. In practice, lithology is central to lithostratigraphy, enabling correlation of rock units across exposure and boreholes.

Methods include field logging of lithology, hand specimen analysis, petrographic microscopy (thin sections), and laboratory techniques such as X-ray diffraction and geochemical assays. Data are integrated into lithologic logs and lithology maps used in geological models, mineral exploration, groundwater assessments, and civil engineering projects.

Etymologically, lithologiaan derives from Greek lithos "stone" and -logia "study of," and in Finnish usage corresponds to the study and description of rocks, though regional terminology may vary.