Finkl, C.W. and Makowski, C., 2020. Lateral extrapolation of coastal catenary sequences using the Biophysical Cross-shore Classification System (BCCS) to create shore-parallel situational zonation mapping units. Journal of Coastal Research, 36(3), 457–471. Coconut Creek (Florida), ISSN 0749-0208.The Biophysical Cross-shore Classification System (BCCS), which uses transects to assess shore-normal ecological and geomorphological successions from offshore to onshore within a coastal belt (Finkl and Makowski, 2020a), also provides a basis for extrapolating cross-shore catenas into shore-parallel units. This paper shows that three-dimensional transects can be parameterized in terms of alongshore breadth as well as cross-shore width and depth below or elevation above sea level. The codification of cross-shore environments and habitats in the framework of the BCCS provides an interpretative basis for determining the lateral extent of transect units (archetypes and sub archetypes) by lateral extrapolation to polygonal mapping units. The method discussed here is akin to geological cores or cross-sections that are used to laterally extrapolate units within vertical sequences. Repetitive successions of archetypes, based on cross-shore ecological interpretation of satellite imagery, results in a common master sequence referred to as a Dominant Catenary Sequence (DCS). The DCS is composed of generic archetypes, such as Barrier, Beach, Beach Ridge, Cliff, Coral Reef, Delta, Dune, Flat, Ice, Lagoon, Mountain, Rock, Till (Glacial Material), Upland, and Wetland. The more detailed Coastal Ecological Sequence (CES) of a coastal belt, which is defined by a discrete codification sequence built up from the DCS, is formulated by cognitive geovisual analytics to link the dominant catena with a numbered shore-parallel shape distinction and subscripted sub archetypes to refine the sequential composite archetypes in a DCS. Once the DCS- or CES-labeled transect has been plotted on a satellite image, the identified shore-normal units can be extrapolated into shore-parallel polygons by traditional (i.e. visual, cognitive) image interpretive and mapping techniques to show the spatial extent of classified archetypes and sub archetypes.