Discontinuities in archaeological settlement sequences constitute one of the major challenges in geoarchaeological research, and identifying their origin requires reconstructing the geomorphological processes responsible for sediment accumulation within archaeological sites. The open-air archaeological site of Komishani, located adjacent to Komishan Cave in Mazandaran Province, northern Iran, preserves evidence of human occupation dating from the Mesolithic to the Bronze Age. Occupational hiatus, occurring between the archaeological horizons and dated to between 8600 and 8200 BCE, has raised important questions regarding the origin of the natural deposits responsible for the interruption. To address this issue, sedimentological analyses and geomorphological observations were integrated to reconstruct the depositional history of the site. Sediment samples were analyzed using dry sieving, grain-size distribution, statistical grain-size parameters, and morphometric indices of coarse clasts. The results indicate that the natural deposits are predominantly composed of coarse-grained sediments exhibiting poor to very poor sorting. The predominance of discoidal and bladed clasts, moderate sphericity, angular particle morphology, lithological similarity between the clasts and adjacent limestone outcrops, together with the geomorphological characteristics of the area, including steep hillslopes, faulted geological structures, and unstable bedrock, indicate a local sediment source and short transport distances. Collectively, these lines of evidence suggest that the deposits were generated by hillslope and mass-wasting processes, which rapidly transported and accumulated clastic materials, burying parts of the occupation surface and producing the observed sedimentary discontinuity within the archaeological sequence. These findings emphasize the fundamental role of geomorphological processes in controlling natural sediment accumulation and generating occupational discontinuities in archaeological sites.