79-3 A Gypseous Soil Chronosequence on a Long Parabolic Dune, White Sands National Park, New Mexico, USA

Session: Soil, Dust, and Everything in Between: Current, Quaternary and Earlier Geological Processes and Records

Presenting Author:

Mark Sweeney

Authors:

Sweeney, Mark R.¹, Pietrasiak, Nicole², Bustos, David³, Alameda-Martin, Aitor⁴

(1) U. South Dakota, Vermillion, SD, USA, (2) University of Nevada, Las Vegas, Las Vegas, NV, USA, (3) White Sands National Park, Holloman AFB, NM, USA, (4) University of Almeria, Almeria, Spain,

Abstract:

White Sands National Park in New Mexico is the largest gypsum dune field in the world, bounded on its southern border by a ~20 km-long arm of a vegetated parabolic dune. Prevailing winds are from the southwest and the arm of the parabolic dune becomes progressively younger in the downwind direction to the northeast. Previous work has demonstrated that these parabolic dunes may be as old as ~12 ka, derived from the wind erosion of late Pleistocene Lake Otero, and were occupied by ancient indigenous people. We described a soil chronosequence at the crest of the long parabolic dune arm at five different developmental stages demonstrating the succession from active to inactive stabilized soils with associated microhabitats. The geomorphology of the parabolic dune arm differs by age, with the younger part of the dune containing adjacent blowouts and migrating sand with steep, active slipfaces. The upwind, older part of the dune arm is entirely stabilized with a hard gypsum crust, lower dune heights and slope angles. From young to old, pedogenic development increases as showcased by increased 1) biological soil crust development, 2) gypsum cementation at the surface, 3) travertinic development, 4) calcium carbonate accumulation, 5) rhizolith exposure, and 6) erosion. Gypseous soils, where the parent material is primarily gypsum, are susceptible to dissolution and reprecipitation, leading to surface cementation and travertinic development. Biological soil crust aids in capturing and trapping dust at the surface of the dunes and may be a source of calcium carbonate over time. The gypsum chemical crust, as well as animal activity, have facilitated surface erosion by wind and water of the older stabilized portion of the dune, revealing dense networks of rhizoliths and cemented dune slipfaces at the surface. Compared to more common stabilized quartzo-feldspathic dunes, gypsum parent material may eventually accelerate dune stabilization and rates of erosion as the stabilized dune becomes older due to pervasive crusting and cementation. The fate of these dunes and their cultural resources are threatened by accelerated erosion due to non-native oryx populations that create trails which concentrate overland flow, emphasizing the importance of management in the preservation of park resources.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-9047

© Copyright 2025 The Geological Society of America (GSA), all rights reserved.