Richard L Reynolds
I investigate how climatic variability, weather, and land uses affect surfaces and ecosystems of deserts, with emphasis on sediment eroded, transported, and deposited by wind, mostly as atmospheric dust.
My studies probe the geologic, biologic, and human controls on dust generation as well as the mineralogic and geochemical properties of dust that in turn affect climate, weather, ecosystem health, water resources (effects of dust on melting of snow and ice), ocean fertility, and the health of a large proportion of earth’s people. I have also conducted research on:
- Hawaiian coral-reef health in settings of coastal erosion
- Quaternary climate and responses of landscapes to climatic change and human activities
- Iron-sulfur diagenesis and its effects on lake-sediment paleoenvironmental records
- Magnetic and chemical records of airborne pollution and environmental change
- Paleomagnetism of Tertiary and Quaternary sedimentary and igneous rocks
- Sources of magnetic anomalies in the shallow crust
- Field geology, Antarctica (1970-1971; 1978-1979)
Professional Experience
Research Geologist, USGS (periodic supervisory positions) 1975-2012
Acting Program Manager, Global Change Program USGS 2002
Senior Scientist, USGS 2012-2013 Emeritus since 2013
Adjunct Research Professor, Univ. of Minnesota
Affiliate, Institute for Arctic and Alpine Research Univ. of Colorado
Education and Certifications
Ph.D., Univ. of Colorado, 1975
M.S., Univ. of Colorado, 1970
A.B., Princeton University, 1968
Affiliations and Memberships*
Geological Society of America; Fellow
American Geophysical Union. Assoc. Editor, Jour. Geophysical Res. 1992-1995
Yellowstone-Bighorn Research Assoc.
American Quaternary Assoc.
International Medical Geology Assoc.
International Society for Aeolian Research (guest editor, 2013-14; Board of Directors, 2014-2016)
Honors and Awards
2012 Elected Senior Scientist, USGS
2012-2014 Distinguished Visiting Scholar, School of Geography and the Environment, Univ. of Oxford
2011 Astor Visiting Lecturer for the Humanities, Univ. of Oxford
2007 Co-recipient, Kirk Bryan Award; best publication in Quaternary Geology and Geomorphology, Geological Society of America
Meritorious Service Award, Dept. of the Interior (1995)
1995 Best Paper Award, Jour. Great Lakes Res.
1994 Elected Fellow, Geological Society of America
1993 Visiting Fellow, Institute for Rock Magnetism, Univ. Minnesota
1992 Best Paper Award, Geophysics
Science and Products
Filter Total Items: 116
Dust emission at Franklin Lake Playa, Mojave Desert (USA): Response to meteorological and hydrologic changes 2005-2008
Playa type, size, and setting; playa hydrology; and surface-sediment characteristics are important controls on the type and amount of atmospheric dust emitted from playas. Soft, evaporite-rich sediment develops on the surfaces of some Mojave Desert (USA) playas (wet playas), where the water table is shallow (< 4 m). These areas are sources of atmospheric dust because of continuous or episodic repl
Authors
Richard L. Reynolds, Rian Bogle, John Vogel, Harland L. Goldstein, James Yount
Sediment losses and gains across a gradient of livestock grazing and plant invasion in a cool, semi-arid grassland, Colorado Plateau, USA
Large sediment fluxes can have significant impacts on ecosystems. We measured incoming and outgoing sediment across a gradient of soil disturbance (livestock grazing, plowing) and annual plant invasion for 9 years. Our sites included two currently ungrazed sites: one never grazed by livestock and dominated by perennial grasses/well-developed biocrusts and one not grazed since 1974 and dominated by
Authors
Jayne Belnap, Richard L. Reynolds, Marith C. Reheis, Susan L. Phillips, Frank Urban, Harland L. Goldstein
Paleomagnetism and environmental magnetism of GLAD800 sediment cores from Bear Lake, Utah and Idaho
A ???220,000-year record recovered in a 120-m-long sediment core from Bear Lake, Utah and Idaho, provides an opportunity to reconstruct climate change in the Great Basin and compare it with global climate records. Paleomagnetic data exhibit a geomagnetic feature that possibly occurred during the Laschamp excursion (ca. 40 ka). Although the feature does not exhibit excursional behavior (???40?? dep
Authors
C.W. Heil, J.W. King, J. G. Rosenbaum, R. L. Reynolds, Steven M. Colman
Allogenic sedimentary components of Bear Lake, Utah and Idaho
Bear Lake is a long-lived lake filling a tectonic depression between the Bear River Range to the west and the Bear River Plateau to the east, and straddling the border between Utah and Idaho. Mineralogy, elemental geochemistry, and magnetic properties provide information about variations in provenance of allogenic lithic material in last-glacial-age, quartz-rich sediment in Bear Lake. Grain-size d
Authors
J. G. Rosenbaum, W.E. Dean, R. L. Reynolds, M. C. Reheis
Compositions of modern dust and surface sediments in the Desert Southwest, United States
Modern dusts across southwestern United States deserts are compositionally similar to dust-rich Av soil horizons (depths of 0-0.5 cm and 1-4 cm at 35 sites) for common crustal elements but distinctly different for some trace elements. Chemical compositions and magnetic properties of the soil samples are similar among sites relative to dust sources, geographic areas, and lithologic substrates. Exce
Authors
M. C. Reheis, J. R. Budahn, P. J. Lamothe, R. L. Reynolds
Increasing eolian dust deposition in the western United States linked to human activity
Mineral aerosols from dust are an important influence on climate and on marine and terrestrial biogeochemical cycles. These aerosols are generated from wind erosion of surface soils. The amount of dust emission can therefore be affected by human activities that alter surface sediments. However, changes in regional- and global-scale dust fluxes following the rapid expansion of human populations and
Authors
J. C. Neff, A. P. Ballantyne, G. L. Farmer, N. M. Mahowald, C. C. Landry, J. T. Overpeck, T. H. Painter, C. R. Lawrence, Richard L. Reynolds
Compositional trends in aeolian dust along a transect across the southwestern United States
Aeolian dust strongly influences ecology and landscape geochemistry over large areas that span several desert ecosystems of the southwestern United States. This study evaluates spatial and temporal variations and trends of the physical and chemical properties of dust in the southwestern United States by examining dust deposited in natural depressions on high isolated surfaces along a transect from
Authors
H.L. Goldstein, R. L. Reynolds, M. C. Reheis, J.C. Yount, J. C. Neff
Biogeochemical and ecological impacts of livestock grazing in semi-arid southeastern Utah, USA
Relatively few studies have examined the ecological and biogeochemical effects of livestock grazing in southeastern Utah. In this study, we evaluated how grazing has affected soil organic carbon and nitrogen to a depth of 50 cm in grasslands located in relict and actively-grazed sites in the Canyonlands physiographic section of the Colorado Plateau. We also evaluated differences in plant ground co
Authors
D. P. Fernandez, J. C. Neff, R. L. Reynolds
Dust emission from wet and dry playas in the Mojave Desert, USA
The interactions between playa hydrology and playa-surface sediments are important factors that control the type and amount of dust emitted from playas as a result of wind erosion. The production of evaporite minerals during evaporative loss of near-surface ground water results in both the creation and maintenance of several centimeters or more of loose sediment on and near the surfaces of wet pla
Authors
Richard L. Reynolds, James C. Yount, Marith C. Reheis, Harland L. Goldstein, Pat F. Chavez, Robert E. Fulton, John W. Whitney, Christopher C. Fuller, Richard M. Forester
Performance of Bromus tectorum L. in relation to soil properties, water additions, and chemical amendments in calcareous soils of southeastern Utah, USA
In drylands of southeastern Utah, USA, the invasive exotic grass Bromus tectorum L. occurs in distinct spatial patterns suggesting soil control of ecosystem susceptibility to invasion. To improve our understanding of these patterns, we examined performance of B. tectorum in relation to additions of water, KCl, MgO, and CaO at seventeen 1600 m2 sites distributed across a calcareous soil gradient in
Authors
Mark E. Miller, Jayne Belnap, Susan W. Beatty, Richard L. Reynolds
Quantity, composition, and source of sediment collected in sediment traps along the fringing coral reef off Molokai, Hawaii
Sediment traps were used to evaluate the frequency, cause, and relative intensity of sediment mobility/resuspension along the fringing coral reef off southern Molokai (February 2000–May 2002). Two storms with high rainfall, floods, and exceptionally high waves resulted in sediment collection rates > 1000 times higher than during non-storm periods, primarily because of sediment resuspension by wave
Authors
Michael H. Bothner, R. L. Reynolds, M.A. Casso, C. D. Storlazzi, M.E. Field
Composition of aeolian dust in natural traps on isolated surfaces of the central Mojave Desert - Insights to mixing, sources, and nutrient inputs
The recognition and characterization of aeolian dust in soil contribute to a better understanding of landscape and ecosystem dynamics of drylands. Results of this study show that recently deposited dust, sampled in isolated, mostly high-ground settings, is chemically and mineralogically similar on varied geologic substrates over a large area (15 000 km2) in the Mojave Desert. The silt-plus-clay fr
Authors
R. L. Reynolds, M. Reheis, J. Yount, P. Lamothe
Non-USGS Publications**
Larson, E.E., Reynolds, R.L., and others, 1975, Major element petrochemistry of some extrusive rocks from the volcanically active Mariana Islands: Bulletin Volcanologique, v. 39, p. 361-377.
Larson, E.E., Reynolds, R.L., and others, 1975, Paleomagnetism of Miocene volcanics of Guam and the curvature of the southern Mariana Island Arc: Geological Society America Bulletin, v. 86, p. 346‑350.
Levi, S., Merrill, R.T., Larson, E.E., Reynolds, R.L., and others, 1975, Paleosecular variation of lavas from the Marianas in the Western Pacific Ocean: Journal Geomagnetism and Geoelectricity, v. 27, p. 57-66.
Rowley, P.D., Williams, P.L., Schmidt, D.L., Reynolds, R.L., and others, 1975, Copper mineralization along the Lassiter Coast of the Antarctic Peninsula: Economic Geology, v. 70, p. 982‑992.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 116
Dust emission at Franklin Lake Playa, Mojave Desert (USA): Response to meteorological and hydrologic changes 2005-2008
Playa type, size, and setting; playa hydrology; and surface-sediment characteristics are important controls on the type and amount of atmospheric dust emitted from playas. Soft, evaporite-rich sediment develops on the surfaces of some Mojave Desert (USA) playas (wet playas), where the water table is shallow (< 4 m). These areas are sources of atmospheric dust because of continuous or episodic repl
Authors
Richard L. Reynolds, Rian Bogle, John Vogel, Harland L. Goldstein, James Yount
Sediment losses and gains across a gradient of livestock grazing and plant invasion in a cool, semi-arid grassland, Colorado Plateau, USA
Large sediment fluxes can have significant impacts on ecosystems. We measured incoming and outgoing sediment across a gradient of soil disturbance (livestock grazing, plowing) and annual plant invasion for 9 years. Our sites included two currently ungrazed sites: one never grazed by livestock and dominated by perennial grasses/well-developed biocrusts and one not grazed since 1974 and dominated by
Authors
Jayne Belnap, Richard L. Reynolds, Marith C. Reheis, Susan L. Phillips, Frank Urban, Harland L. Goldstein
Paleomagnetism and environmental magnetism of GLAD800 sediment cores from Bear Lake, Utah and Idaho
A ???220,000-year record recovered in a 120-m-long sediment core from Bear Lake, Utah and Idaho, provides an opportunity to reconstruct climate change in the Great Basin and compare it with global climate records. Paleomagnetic data exhibit a geomagnetic feature that possibly occurred during the Laschamp excursion (ca. 40 ka). Although the feature does not exhibit excursional behavior (???40?? dep
Authors
C.W. Heil, J.W. King, J. G. Rosenbaum, R. L. Reynolds, Steven M. Colman
Allogenic sedimentary components of Bear Lake, Utah and Idaho
Bear Lake is a long-lived lake filling a tectonic depression between the Bear River Range to the west and the Bear River Plateau to the east, and straddling the border between Utah and Idaho. Mineralogy, elemental geochemistry, and magnetic properties provide information about variations in provenance of allogenic lithic material in last-glacial-age, quartz-rich sediment in Bear Lake. Grain-size d
Authors
J. G. Rosenbaum, W.E. Dean, R. L. Reynolds, M. C. Reheis
Compositions of modern dust and surface sediments in the Desert Southwest, United States
Modern dusts across southwestern United States deserts are compositionally similar to dust-rich Av soil horizons (depths of 0-0.5 cm and 1-4 cm at 35 sites) for common crustal elements but distinctly different for some trace elements. Chemical compositions and magnetic properties of the soil samples are similar among sites relative to dust sources, geographic areas, and lithologic substrates. Exce
Authors
M. C. Reheis, J. R. Budahn, P. J. Lamothe, R. L. Reynolds
Increasing eolian dust deposition in the western United States linked to human activity
Mineral aerosols from dust are an important influence on climate and on marine and terrestrial biogeochemical cycles. These aerosols are generated from wind erosion of surface soils. The amount of dust emission can therefore be affected by human activities that alter surface sediments. However, changes in regional- and global-scale dust fluxes following the rapid expansion of human populations and
Authors
J. C. Neff, A. P. Ballantyne, G. L. Farmer, N. M. Mahowald, C. C. Landry, J. T. Overpeck, T. H. Painter, C. R. Lawrence, Richard L. Reynolds
Compositional trends in aeolian dust along a transect across the southwestern United States
Aeolian dust strongly influences ecology and landscape geochemistry over large areas that span several desert ecosystems of the southwestern United States. This study evaluates spatial and temporal variations and trends of the physical and chemical properties of dust in the southwestern United States by examining dust deposited in natural depressions on high isolated surfaces along a transect from
Authors
H.L. Goldstein, R. L. Reynolds, M. C. Reheis, J.C. Yount, J. C. Neff
Biogeochemical and ecological impacts of livestock grazing in semi-arid southeastern Utah, USA
Relatively few studies have examined the ecological and biogeochemical effects of livestock grazing in southeastern Utah. In this study, we evaluated how grazing has affected soil organic carbon and nitrogen to a depth of 50 cm in grasslands located in relict and actively-grazed sites in the Canyonlands physiographic section of the Colorado Plateau. We also evaluated differences in plant ground co
Authors
D. P. Fernandez, J. C. Neff, R. L. Reynolds
Dust emission from wet and dry playas in the Mojave Desert, USA
The interactions between playa hydrology and playa-surface sediments are important factors that control the type and amount of dust emitted from playas as a result of wind erosion. The production of evaporite minerals during evaporative loss of near-surface ground water results in both the creation and maintenance of several centimeters or more of loose sediment on and near the surfaces of wet pla
Authors
Richard L. Reynolds, James C. Yount, Marith C. Reheis, Harland L. Goldstein, Pat F. Chavez, Robert E. Fulton, John W. Whitney, Christopher C. Fuller, Richard M. Forester
Performance of Bromus tectorum L. in relation to soil properties, water additions, and chemical amendments in calcareous soils of southeastern Utah, USA
In drylands of southeastern Utah, USA, the invasive exotic grass Bromus tectorum L. occurs in distinct spatial patterns suggesting soil control of ecosystem susceptibility to invasion. To improve our understanding of these patterns, we examined performance of B. tectorum in relation to additions of water, KCl, MgO, and CaO at seventeen 1600 m2 sites distributed across a calcareous soil gradient in
Authors
Mark E. Miller, Jayne Belnap, Susan W. Beatty, Richard L. Reynolds
Quantity, composition, and source of sediment collected in sediment traps along the fringing coral reef off Molokai, Hawaii
Sediment traps were used to evaluate the frequency, cause, and relative intensity of sediment mobility/resuspension along the fringing coral reef off southern Molokai (February 2000–May 2002). Two storms with high rainfall, floods, and exceptionally high waves resulted in sediment collection rates > 1000 times higher than during non-storm periods, primarily because of sediment resuspension by wave
Authors
Michael H. Bothner, R. L. Reynolds, M.A. Casso, C. D. Storlazzi, M.E. Field
Composition of aeolian dust in natural traps on isolated surfaces of the central Mojave Desert - Insights to mixing, sources, and nutrient inputs
The recognition and characterization of aeolian dust in soil contribute to a better understanding of landscape and ecosystem dynamics of drylands. Results of this study show that recently deposited dust, sampled in isolated, mostly high-ground settings, is chemically and mineralogically similar on varied geologic substrates over a large area (15 000 km2) in the Mojave Desert. The silt-plus-clay fr
Authors
R. L. Reynolds, M. Reheis, J. Yount, P. Lamothe
Non-USGS Publications**
Larson, E.E., Reynolds, R.L., and others, 1975, Major element petrochemistry of some extrusive rocks from the volcanically active Mariana Islands: Bulletin Volcanologique, v. 39, p. 361-377.
Larson, E.E., Reynolds, R.L., and others, 1975, Paleomagnetism of Miocene volcanics of Guam and the curvature of the southern Mariana Island Arc: Geological Society America Bulletin, v. 86, p. 346‑350.
Levi, S., Merrill, R.T., Larson, E.E., Reynolds, R.L., and others, 1975, Paleosecular variation of lavas from the Marianas in the Western Pacific Ocean: Journal Geomagnetism and Geoelectricity, v. 27, p. 57-66.
Rowley, P.D., Williams, P.L., Schmidt, D.L., Reynolds, R.L., and others, 1975, Copper mineralization along the Lassiter Coast of the Antarctic Peninsula: Economic Geology, v. 70, p. 982‑992.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government