Debra A Willard, Ph.D.
I am a palynologist (pollen and spores) with expertise in paleoecology and biostratigraphy. My biostratigraphic expertise extends from the Carboniferous to the Holocene, with an emphasis on Euramerica (Paleozoic) and the Northern Hemisphere. My paleoecological expertise includes the late Paleozoic and the Paleogene to Holocene intervals.
Editorial Boards
- Global and Planetary Change
- Frontiers in Ecology and Evolution – Paleoecology section Review Editor
- Quaternary
- Review of Palaeobotany and Palynology
Professional Experience
2021-Present Research Geologist, US Geological Survey, Reston, Virginia
2011-2021 Coordinator, USGS Land Change Science Program
1991-2011 Research Geologist, US Geological Survey, Reston, Virginia
1990-1991 Postdoctoral Researcher, National Museum of Natural History, Smithsonian Institution, Washington, DC
Education and Certifications
University of Illinois at Urbana-Champaign - Ph.D., Botany 1990
University of Illinois at Urbana-Champaign - M.S., Botany 1985
The Pennsylvania State University - B.S., Botany 1982
Stephens College - A.A., Geology 1980
Affiliations and Memberships*
American Geophysical Union
Geological Society of America
The Palynological Society
Science and Products
Filter Total Items: 105
Preliminary analysis of down-core biotic assemblages Bob Allen Keys, Everglades National Park, Florida Bay Preliminary analysis of down-core biotic assemblages Bob Allen Keys, Everglades National Park, Florida Bay
Introduction A series of short piston cores ( 2m) were taken from eleven stations in Florida Bay in May, 1994 by researchers from the U.S. Geological Survey (St. Petersburg, FL., Woods Hole, MA., and Denver CO.) in cooperation with South Florida Water Management District, and the Everglades National Park, and the National Oceanic and Atmospheric Administration (NOAA). Core 6A from Bob...
Authors
G. L. Brewster-Wingard, S. E. Ishman, Thomas M. Cronin, Lucy E. Edwards, Debra A. Willard, R. B. Halley
Paleoecology of the Springfield Coal Member (Desmoinesian, Illinois Basin) near the Leslie Cemetery paleochannel, southwestern Indiana Paleoecology of the Springfield Coal Member (Desmoinesian, Illinois Basin) near the Leslie Cemetery paleochannel, southwestern Indiana
The Springfield Coal Member (Carbondale Group, Petersburg Formation of Indiana) is split locally in Warrick and Gibson Counties, Indiana, by clastic rocks of the Folsomville Member (Carbondale Group, Petersburg Formation) that represent the Leslie Cemetery paleochannel, part of a large, interconnected paleochannel system in the Springfield coal bed. This study incorporated analysis of...
Authors
Debra A. Willard, William A. DiMichele, Donald L. Eggert, James C. Hower, Carl B. Rexroad, Andrew C. Scott
Joint investigations of the Middle Pliocene climate I: PRISM paleoenvironmental reconstructions Joint investigations of the Middle Pliocene climate I: PRISM paleoenvironmental reconstructions
The Pliocene epoch represents an important transition from a climate regime with high-frequency, low-amplitude oscillations when the Northern Hemisphere lacked substantial ice sheets, to the typical high-frequency, high-amplitude Middle to Late Pleistocene regime characterized by glacial—interglacial cycles that involve waxing and waning of major Northern Hemisphere ice sheets. Analysis...
Authors
Harry J. Dowsett, Robert S. Thompson, John A. Barron, Thomas M. Cronin, Farley R. Fleming, Scott Ishman, Richard Z. Poore, Debra A. Willard, Thomas R. Holtz
Palynological record from the North Atlantic region at 3 Ma: Vegetational distribution during a period of global warmth Palynological record from the North Atlantic region at 3 Ma: Vegetational distribution during a period of global warmth
Pollen assemblages from five mid-Pliocene, deep-marine and shallow-marine sites in the North Atlantic Ocean region were analyzed quantitatively to estimate vegetational composition and terrestrial paleoclimates during a time interval centered at about 3 Ma. Three subarctic sites (58–67°N latitude) from the Norwegian Sea, northern Iceland, and the Labrador Sea yielded pollen assemblages
Authors
Debra A. Willard
PRISM 8 degrees X 10 degrees North Hemisphere paleoclimate reconstruction; digital data PRISM 8 degrees X 10 degrees North Hemisphere paleoclimate reconstruction; digital data
The PRISM 8?x10? data set represents several years of investigation by PRISM (Pliocene Research, Interpretation, and Synoptic Mapping) Project members. One of the goals of PRISM is to produce time-slice reconstructions of intervals of warmer than modern climate within the Pliocene Epoch. The first of these was chosen to be at 3.0 Ma (time scale of Berggren et al., 1985) and is published...
Authors
John A. Barron, Thomas M. Cronin, Harry J. Dowsett, Farley R. Fleming, Thomas R. Holtz, Scott E. Ishman, Richard Z. Poore, Robert S. Thompson, Debra A. Willard
Paleobotany and palynology of the Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of the Illinois Basin (Upper Pennsylvanian) Paleobotany and palynology of the Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of the Illinois Basin (Upper Pennsylvanian)
No abstract available.
Authors
Debra A. Willard, T.L. Phillips
Pliocene palynomorph census data from the Pinecrest Beds (Tamiami Formation) in Quality Aggregates Phase 6 Pit, southwestern Florida Pliocene palynomorph census data from the Pinecrest Beds (Tamiami Formation) in Quality Aggregates Phase 6 Pit, southwestern Florida
No abstract available.
Authors
Debra A. Willard
Terrestrial and marine records of climatic and environmental changes during the Pliocene in subtropical Florida Terrestrial and marine records of climatic and environmental changes during the Pliocene in subtropical Florida
Pollen, ostracode, and benthic foraminifer assemblages deposited during sea-level high-stands in subtropical Florida record a climate change during the period 4.5-1.0 Ma. Before 3.5 Ma, open-shelf marine faunas and pollen assemblages with abundant Pinus, Quercus, Fagus, Carya, and nonarboreal pollen were present, indicating cooler conditions than today. From ∼3.5 to 1.0 Ma, marine and...
Authors
Debra A. Willard, T. M. Cronin, S. E. Ishman, R. J. Litwin
Science and Products
Filter Total Items: 105
Preliminary analysis of down-core biotic assemblages Bob Allen Keys, Everglades National Park, Florida Bay Preliminary analysis of down-core biotic assemblages Bob Allen Keys, Everglades National Park, Florida Bay
Introduction A series of short piston cores ( 2m) were taken from eleven stations in Florida Bay in May, 1994 by researchers from the U.S. Geological Survey (St. Petersburg, FL., Woods Hole, MA., and Denver CO.) in cooperation with South Florida Water Management District, and the Everglades National Park, and the National Oceanic and Atmospheric Administration (NOAA). Core 6A from Bob...
Authors
G. L. Brewster-Wingard, S. E. Ishman, Thomas M. Cronin, Lucy E. Edwards, Debra A. Willard, R. B. Halley
Paleoecology of the Springfield Coal Member (Desmoinesian, Illinois Basin) near the Leslie Cemetery paleochannel, southwestern Indiana Paleoecology of the Springfield Coal Member (Desmoinesian, Illinois Basin) near the Leslie Cemetery paleochannel, southwestern Indiana
The Springfield Coal Member (Carbondale Group, Petersburg Formation of Indiana) is split locally in Warrick and Gibson Counties, Indiana, by clastic rocks of the Folsomville Member (Carbondale Group, Petersburg Formation) that represent the Leslie Cemetery paleochannel, part of a large, interconnected paleochannel system in the Springfield coal bed. This study incorporated analysis of...
Authors
Debra A. Willard, William A. DiMichele, Donald L. Eggert, James C. Hower, Carl B. Rexroad, Andrew C. Scott
Joint investigations of the Middle Pliocene climate I: PRISM paleoenvironmental reconstructions Joint investigations of the Middle Pliocene climate I: PRISM paleoenvironmental reconstructions
The Pliocene epoch represents an important transition from a climate regime with high-frequency, low-amplitude oscillations when the Northern Hemisphere lacked substantial ice sheets, to the typical high-frequency, high-amplitude Middle to Late Pleistocene regime characterized by glacial—interglacial cycles that involve waxing and waning of major Northern Hemisphere ice sheets. Analysis...
Authors
Harry J. Dowsett, Robert S. Thompson, John A. Barron, Thomas M. Cronin, Farley R. Fleming, Scott Ishman, Richard Z. Poore, Debra A. Willard, Thomas R. Holtz
Palynological record from the North Atlantic region at 3 Ma: Vegetational distribution during a period of global warmth Palynological record from the North Atlantic region at 3 Ma: Vegetational distribution during a period of global warmth
Pollen assemblages from five mid-Pliocene, deep-marine and shallow-marine sites in the North Atlantic Ocean region were analyzed quantitatively to estimate vegetational composition and terrestrial paleoclimates during a time interval centered at about 3 Ma. Three subarctic sites (58–67°N latitude) from the Norwegian Sea, northern Iceland, and the Labrador Sea yielded pollen assemblages
Authors
Debra A. Willard
PRISM 8 degrees X 10 degrees North Hemisphere paleoclimate reconstruction; digital data PRISM 8 degrees X 10 degrees North Hemisphere paleoclimate reconstruction; digital data
The PRISM 8?x10? data set represents several years of investigation by PRISM (Pliocene Research, Interpretation, and Synoptic Mapping) Project members. One of the goals of PRISM is to produce time-slice reconstructions of intervals of warmer than modern climate within the Pliocene Epoch. The first of these was chosen to be at 3.0 Ma (time scale of Berggren et al., 1985) and is published...
Authors
John A. Barron, Thomas M. Cronin, Harry J. Dowsett, Farley R. Fleming, Thomas R. Holtz, Scott E. Ishman, Richard Z. Poore, Robert S. Thompson, Debra A. Willard
Paleobotany and palynology of the Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of the Illinois Basin (Upper Pennsylvanian) Paleobotany and palynology of the Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of the Illinois Basin (Upper Pennsylvanian)
No abstract available.
Authors
Debra A. Willard, T.L. Phillips
Pliocene palynomorph census data from the Pinecrest Beds (Tamiami Formation) in Quality Aggregates Phase 6 Pit, southwestern Florida Pliocene palynomorph census data from the Pinecrest Beds (Tamiami Formation) in Quality Aggregates Phase 6 Pit, southwestern Florida
No abstract available.
Authors
Debra A. Willard
Terrestrial and marine records of climatic and environmental changes during the Pliocene in subtropical Florida Terrestrial and marine records of climatic and environmental changes during the Pliocene in subtropical Florida
Pollen, ostracode, and benthic foraminifer assemblages deposited during sea-level high-stands in subtropical Florida record a climate change during the period 4.5-1.0 Ma. Before 3.5 Ma, open-shelf marine faunas and pollen assemblages with abundant Pinus, Quercus, Fagus, Carya, and nonarboreal pollen were present, indicating cooler conditions than today. From ∼3.5 to 1.0 Ma, marine and...
Authors
Debra A. Willard, T. M. Cronin, S. E. Ishman, R. J. Litwin
*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