Kerrostuva

Kerrostuva is a Finnish adjective meaning layered or stratified. It is used to describe materials, structures, or landscapes where matter has accumulated in distinct layers. The term is common in geology, where it characterizes sediments and rocks formed by deposition in successive beds, but it can also apply to soils or man-made sequences that show clear layering.

In geology, kerrostuva describes bedding and stratification visible in sedimentary rocks. Layering arises from changes in sediment supply, energy conditions, or depositional environments over time, such as river channels, deltas, lakes, or marine settings. The result is bedding planes that separate layers with different grain size, composition, or color. Sedimentary rocks such as shale, sandstone, and limestone display kerrostuva structure to varying degrees. In some cases, secondary processes like compaction or diagenesis accentuate or diminish visible layering.

Beyond rocks, the concept appears in soil science and geomorphology, where soil profiles or landforms can show vertical or horizontal layering. Layering can reflect historical changes in climate, vegetation, or disturbance.

Etymology-wise, kerrostuva derives from kerros (layer, floor) and the sense of accumulating in layers through the verb kerrostua. Related terms include kerrostuminen (the process of becoming layered) and kerrostuneisuus (the state of being layered). The usage is primarily scientific, with the term serving as a concise descriptor for stratified natural materials and formations.