lithological

The term lithological relates to lithology, the branch of geology that studies the physical characteristics of rocks. It focuses on rock type, mineral composition, texture, grain size, color, layering, and weathering features to describe and classify rocks in a locality or stratigraphic unit. Lithological information is essential for interpreting geologic history and for building geological maps.

In practice, lithology is used to define lithologies and lithostratigraphic units dominated by particular rock types, such as sandstone, shale, limestone, dolostone, or igneous and metamorphic rocks. Descriptions can be made at the outcrop, borehole, or core scale, and may be complemented by microscopic petrography, X-ray diffraction, and geochemical analyses to identify minerals and textures.

Field and laboratory techniques produce a lithological log or description sheet that records attributes such as color, grain size, sorting, cementation, porosity indicators, fossil content, bedding or foliation, and diagenetic features. These data support interpretations of depositional environment, diagenesis, and tectonic history, and underpin practical tasks in resource exploration, groundwater studies, and engineering geology.

Applications include hydrocarbon exploration and reservoir characterization, groundwater assessment, mineral exploration, environmental geology, and construction planning. The term lithological is widely used to describe the rock-based character of a region or formation and is often used alongside lithostratigraphy and lithology to organize geological description.