U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2011-3085 

July 2011

Monitoring and Analysis of Sand Dune Movement and 

Growth on the Navajo Nation, Southwestern United States

An increasingly dry climate in the U.S. Southwest has led to accelerated migration of active sand dunes and 

reactivation of previously inactive dunes. In the Native lands of the Colorado Plateau, sand dunes and sand 

sheets cover one-third of the area. Migration of these dunes can threaten housing and roads, as at this Navajo 

settlement. Dominant wind direction (arrow) is to the northeast. (USGS photo by Jon Mason.)

U.S. Geological 

Survey (USGS) 

scientists have been 

studying the migration 

of sand dunes and the 

movement of sand 

and dust at several 

sites (diamonds) 

within the lands of 

the Navajo Nation. 

These studies indicate 

increasing movement 

of dunes, which is a 

cause for concern to 

local communities.

stabilized by vegetation), partly active 

(exposed dune crests with some vegetation 

cover), and fully active (wind-driven with no 

vegetation cover). 

U.S. Geological Survey (USGS) scientists 

are conducting research with the aim of 

providing critical data to the Native peoples 

of the region in response to growing dune 

activity, diminished vegetation cover, and an 

increasingly arid environment (Redsteer, 

2002). The USGS interdisciplinary studies 

are focused on understanding the processes 

responsible for initiation of eolian (windblown) sand movement, including the 

influence of source sediment availability, 

climate, vegetation, and land use. Reactivation 

of inactive dunes could have serious 

consequences on human and animal 

Introduction

The Native Navajo people of the southwestern United States are currently 

challenged by an increasingly dry climate. 

Increased aridity from warmer temperatures, 

combined with recurring drought, has 

resulted in a large amount of migrating sand 

that threatens housing, health, and 

transportation. More than one-third of Native 

lands on the Colorado Plateau (Navajo 

Nation and Hopi Tribal Lands) are covered 

with sand dunes and sand sheets. Such dunes 

and sand sheets are common features of arid 

and semiarid environments across the globe, 

where specific conditions of abundant sand 

supply, wind, and minimum vegetation cover 

promote their occurrence. Existing dunes can 

be grouped into three climatic threshold 

classes (Lancaster, 1988): immobile (fully 

Recurring drought and rising temperatures have caused 

reactivation and renewed growth of 

sand dunes on the lands of the Navajo 

Nation on the Colorado Plateau. 

Migrating dunes threaten health, 

housing, and transportation pathways. 

U.S. Geological Survey (USGS) 

scientists are conducting research 

to better understand the processes 

of dune growth and movement. This 

research will provide critical data to 

the Native peoples of the region in their 

response to the changing environment.

Hopi Tribal Lands

Hopi

Grand Falls Site

Navajo Nation

Navajo Nation

UTAH COLORADO

NEW

MEXICO

ARIZONA

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populations, agriculture, grazing, and 

infrastructure on the Navajo Nation and 

similar areas of the Southwest. Annual 

rainfall in the western Navajo Nation has 

fallen below 3 inches (75 mm) during the 

most recent drought (Redsteer and others, 

2010). As a result, the areal extent of sand 

susceptible to mobilization has increased 

significantly. Moreover, regionally significant 

sand and dust storms are becoming 

commonplace during the spring, which is 

typically dry and windy. 

Methods and Results

Monitoring efforts to measure rates of 

dune movement and growth in active dune 

fields are accomplished through a number 

of methods. The migration of dunes is 

measured by combining surficial mapping 

with aerial and satellite imagery, GPS (global 

positioning system), and ground-based lidar 

(light detection and ranging) measurements. 

Rates of dune movement and the incidence 

of accompanying dust storms are compared 

to meteorological conditions measured at 

established monitoring sites. An historical 

survey of available aerial and satellite 

imagery, with resolutions of 3.3 feet (1 m) per 

pixel or better, has been compiled for the dune 

field studied. The compiled imagery spans 

the lifetime of the dune field, from before its 

appearance in the mid 1950s until 2010. In 

each image, the leading edge of the active 

dune field was identified and delineated, 

Prevailing wind
facilitating calculations of the areal extent and 

migration-rate changes for the dune field over 

the past 60 years.

Survey-grade GPS instruments allow the 

mapping and monitoring of dune slip faces to 

within 4 inches (10 cm) while also providing great flexibility in timing data-collection 

efforts. The ground-based lidar was used to 

record volumetric changes in two individual 

dunes within the Grand Falls monitoring 

site (see map). The lidar instrument collects 

data at six locations surrounding each dune, 

recording millions of relative point locations 

in three dimensions during its scans. These 

data allow the creation of highly detailed spatial models of the dunes. Repeat scans, before 

and after the winter/spring windy season, help 

in understanding the geomorphic changes of 

the dunes as they move across the landscape.

Measurements of dune migration are 

accompanied by meteorological monitoring 

to understand conditions that contribute to 

differing rates of sand transport and dune 

movement. The Grand Falls monitoring 

station is equipped with a precipitation gage, 

a temperature probe, soil moisture probe, and 

anemometers at the upwind and downwind 

portions of the dune field that measure wind 

direction and speed. It also has a digital 

camera that captures images when wind 

speeds exceed 10 miles per hour (15 km/hr), 

providing visual evidence of sediment 

movement across the surface during windstorms and information on visibility during 

dust storms. These data are being used to 

evaluate how weather fluctuations contribute 

to changes in dune shape, size, and migration 

rates, and under what conditions sand storms 

are accompanied by dust transport.

The results of this research show that the 

rate of dune migration in active regions varies 

from year to year, depending on local 

meteorological conditions. In 2009, an 

unusually windy and dry year, we measured 

dune migration rates as high as 112-157 feet 

per year (34 to 48 m/yr), depending on the 

locality. With current drought conditions and 

typical springtime winds, dunes in the region 

of study can move more than 3.3 feet (1 m) in 

a single windstorm. The overall size of active 

dune fields and the overall number of dunes 

have also changed. Assessment of archived 

imagery shows that the Grand Falls dune field 

has grown in areal extent by 70 percent (both 

laterally and downwind) from 1992 to 2007, a 

period of only 15 years.

Conclusion

Initial data from this study indicate that 

sand-dune migration rates are currently about 

115 feet per year (35 m/yr) or more in the arid 

southwestern portion of the Navajo Nation. 

Fieldwork and data from photo archives show 

growth of active dune fields and reactivation 

of formerly stabilized surfaces. The formation and movement of active dunes on the 

downwind side of stream-bed sand sources is 

presently endangering housing and transportation, potentially jeopardizing native plants 

and grazing lands, increasing health hazards 

to humans and animals, and affecting regional 

air quality.

A more complete understanding of the 

complex environmental processes that 

have such a profound influence on the 

Navajo Nation requires more detailed 

datasets. USGS scientists, with the 

cooperation of Navajo communities, are 

working to expand the sensor network in 

the southwestern Navajo Nation and 

concurrently develop new analysis 

techniques. The resulting analyses will 

provide the Navajo people with a deeper 

Archival imagery has allowed 

plotting the migration of the 

dune field at the Grand Falls 

site (see map) from 1953 to 

2010. Left: Here the dune front 

at various times is plotted 

on an image from 2005. The 

dominant wind direction has 

been from the southwest (lower 

left) throughout the time period 

studied. Right: Enlarged view of 

a small part of the Grand Falls 

dune field showing recent (2005 

to 2010) migration of dunes 

plotted on a satellite image 

taken in 2005. These dunes 

are migrating at a rapid rate—

more than 330 feet 

(100 m) in just 5 years.

understanding of the processes driving dune 

migration and will help identify possible 

techniques for mitigating hazards from sand 

and dust transport.

References

Lancaster, N., 1988, Development of linear dunes in the 

southwestern Kalahari, southern Africa: Journal of 

Arid Environments, v. 14, p. 233-244.

Redsteer, M.H., 2002, Factors effecting dune mobility on the Navajo Nation, Arizona, USA, in 5th 

International Conference on Aeolian Research and 

The Global Change & Terrestrial Ecosystem-Soil 

Erosion Network, Lubbock Texas, July 22-25, 2002, 

Proceedings: Lubbock Texas, Texas Tech University, 

International Center for Arid and Semiarid Lands 

Studies, Publication number 02-2, p. 385.

Redsteer, M.H., Bogle, R., Vogel, J., Block, D., Velasco, 

M., and Middleton, B., 2010, The history and growth 

of a recent dune field at Grand Falls, Navajo Nation, 

NE Arizona [abs.]: Geological Society of America 

Abstracts with Programs, v. 42, no. 5, p. 416.

For more information contact:

Margaret Hiza Redsteer

U.S. Geological Survey, 2255 North Gemini Drive

Flagstaff, AZ 86001

mhiza@usgs.gov

http://geomaps.wr.usgs.gov/navajo/index.htm

http://sgst.wr.usgs.gov/dunes/

This fact sheet and any updates to it are available 

online at

http://pubs.usgs.gov/fs/2011/3085/

Margaret Hiza Redsteer,

Rian C. Bogle, and John M. Vogel

Edited by Peter H. Stauffer

Layout by Jeanne S. DiLeo

The Leupp Chapter of the Navajo Nation passed a resolution in 

support of this research, and of the monitoring site. Our work 

has been conducted with the support of the Navajo Nation 

Department of Water Management, Navajo Nation Historic 

Preservation Office, and a research permit granted by the 

Navajo Nation Department of Minerals. Any persons wishing to 

conduct geologic investigations on the Navajo Nation must first 

apply, and receive, a permit from the Navajo Nation Mineral 

Department, P.O. Box 1910, Window Rock, Arizona 86515, 

telephone (928) 871-6587.

Grand Falls Dune Field

Migration 1953–2010

Detail of Grand Falls Dune Field 

Migration 2005–2010

2007

1953

2009

2010

2005

1997

1992

1979

1968

2010

2007

2009

2010

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