Spring tides, storm surges, and the destruction of coastal middens: A case study from the upper Gulf of California, México

Abstract

This study used photogrammetry to analyze digital video taken before and after a new moon perigean spring tide that caused extensive damage to archaeological sites along the Upper Gulf of California coastline, south of San Felipe, Baja California, México. We created a 3D digital surface model (DSM) and orthophoto of the Conchero 4 site, a large multicomponent shell midden and sand dune. Results showed mass wasting (∼100 linear meters and ∼1500 m³) across the entire east-facing dune front and particularly heavy damage along the site’s southern boundary, which faces the mouth of a large drainage. Our research adds a significant dimension to mounting global evidence that cultural heritage sites are eroding away in a wide variety of types of coastal environments, including low-energy tidally-dominated coastlines like the Upper Gulf of California.

Keywords:

• Spring tides
• storm surges
• coastal erosion
• Gulf of California
• Baja California
• México

Acknowledgements

Thanks to Centro INAH Baja California and the Archaeology Council for their permission and support for this project. We thank Jennie Stott for her assistance with the production of figures. We also thank Jim Potter and Vanessa Mirro from the PaleoWest Foundation. Finally, we thank the editors of The Journal of Coastal and Island Archaeology and anonymous reviewers for helpful comments that greatly improved this paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Permission for this field work was granted by INAH (Permits: 401.1S.3-2017/2440; 401.1S.3-2018/1157) under the project name “Proyecto Registro y Rescate de Sitios Arqueológicos de Baja California: Fase Municipio de Mexicali (Doceava y Treceava Temporada de campo).” Funding was provided by a research grant from the PaleoWest Foundation and support from California State University, Los Angeles.