Seadustikke

Seadustikke is a term used in coastal geoscience to describe fine, dust-like aggregates found in nearshore sediments and in inland deposits derived from coastal sources. The concept refers to a composite material formed from a mix of organic matter, mineral grains, and transient aerosols that originate in the surf zone and are subsequently redistributed by wind and water.

Composition and characteristics

Seadustikke particles typically range from a few micrometers to tens of micrometers. They are a heterogeneous matrix that can include carbonate minerals (such as calcite and aragonite), silica, clay minerals, degraded organic material from marine sources, and occasionally microinclusions of biogenic shells. In modern environments, trace amounts of anthropogenic material, including microplastics, may be incorporated into the aggregates.

Formation and transport

The formation mechanism involves multiple processes in coastal settings: wave-driven production of foam and aerosolized droplets, flocculation of organic-rich sediments, and mechanical aggregation of fine mineral grains. These aggregates can be resuspended by wind or currents and transported inland, where they settle in dune systems, soils, or in sediment cores as discrete layers. Storm events typically increase their inland reach and deposition rate.

Sedimentology and interpretation

Seadustikke layers serve as a potential proxy for past coastal dynamics, including storm frequency, wave energy, and sediment supply. They are studied using grain-size analysis, microscopy, and compositional techniques such as SEM-EDS and isotopic measurements. Their interpretation requires careful separation from other fine aeolian or marine-derived dust sources.

See also

Sea spray aerosol, aeolian dust, coastal sedimentology, marine sediment cores.

Note: Seadustikke is used as a descriptive term in coastal science and may appear in regionally specific literature.