Boletín de la Sociedad Geológica Mexicana Volumen 75, núm. 3, A240823, 2023 http://dx.doi.org/10.18268/BSGM2023v75n3a240823

Morphometry of the Samalayuca dunes, northern Chihuahua, Mexico

Morfometría de las dunas de Samalayuca, norte de Chihuahua, México

Miguel Domínguez-Acosta^1,*, Richard P. Langford², Thomas E. Gill²

¹ Departamento de Ingeniería Civil y Ambiental, Universidad Autónoma de Ciudad Juárez, Ave. del Charro 450 norte, 32310, Ciudad Juárez, Chihuahua, Mexico

² Department of Earth, Environmental and Resource Sciences, The University of Texas at El Paso, 500 West University Avenue, 79968, El Paso, Texas, USA.

* Corresponding author: (M. Domínguez- Acosta) This email address is being protected from spambots. You need JavaScript enabled to view it.

How to cite this article:

Domínguez Acosta, M., Langford, R.P., Gill, T.E., 2023, Morphometry of the Samalayuca dunes, Northern Chihuahua, Mexico: Boletín de la Sociedad Geológica Mexicana, 75 (3), A240823. http://dx.doi.org/10.18268/BSGM2023v75n3a240823

Manuscript received: May 9, 2023; Corrected manuscript received: August 13, 2023; Manuscript accepted: August 22, 2023.

ABSTRACT

The Samalayuca Dunes (SMD) (Médanos de Samalayuca), Chihuahua, México, are one of México’s largest and least studied dune fields, now managed as a Protected Area for their ecological characteristics. We present a morphometric characterization of the dune field based on remote sensing and field studies, to advance understanding of its physical environment. SMD’s generally-fine sands originate from shoreline deposits of Paleolake Palomas, transported eastward (downwind) along an aeolian corridor, accumulating primarily as echo dunes upwind of the sierras of Samalayuca and Presidio. A complex wind regime, with northerly and southerly winds complementing regionally-prevailing southwesterlies, modified by topographic effects, shapes the SMD’s morphology. The sand sea covers ~139.7 km², with ~113.8 km² in the main eastern body and ~25.9 km² in a northwestern subfield. We describe six major dune forms: north to south straight-crested dunes, east to west straight-crested dunes, star dunes, vegetated parabolic dunes, relict transverse dunes, and “megastar” (draa) dunes. Mean interdune centroid spacing is 76.5 m. The active dunes, previously described as an “aklé” pattern, are predominantly straight-crested dune sets oriented near-perpendicular to each other with general north-south and east-west crest orientations, 4-5 m high, spaced ~67 m apart for north-south trending crests and ~53 m for east-west trending crests, representing a nearly perpendicular interference pattern in some locations. The active dunes are superimposed in a compound and complex arrangement on relict remnants of much larger north-northwest trending transverse dune ridges fanning out from south to north-northwest, spaced approximately ~1 km apart and ~50 m high. The easternmost dune ridge contains an active set of at least 15 active megastar and reversing dunes up to 120 m tall, increasing in size and complexity from south to north. As a protected area with historical and ecological value, additional geologic investigations should be performed at the SMD, to help conserve this remarkable geologic feature.

Keywords: dunes, sand, aeolian processes, Samalayuca, Chihuahua.