Allan Kolker
Allan Kolker is a Research Geologist (Scientist Emeritus) with the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.
Allan earned his Ph.D. in geochemistry from Stony Brook University and served on the geology faculty at the University of Nebraska-Lincoln prior to joining the USGS in 1996. His expertise in trace element geochemistry and geochemistry of coal is used in studies of coal quality, impact of energy use on the environment, and potential for recovery of critical elements from energy materials.
During his time as a USGS Research Geologist, Dr. Kolker served actively on committees pertaining to coal and the environment, and on the editorial boards of related journals. He supervised two USGS Mendenhall postdoctoral fellows and obtained extramural support from a range of sources to supplement USGS project activities. His work using the Stanford/USGS SHRIMP-RG ion microprobe showed that rare earth elements (REEs) enter the glass phase in coal fly ash, thereby helping resolve a mystery about how REEs in coal ash occur, but also explaining why these critical elements can be difficult to extract.
Before retiring at the end of 2022, Dr. Kolker received the Department of the Interior’s Distinguished Service Award for his career contributions to understanding coal geochemistry and the impact of its utilization as an energy resource. Most recently, he was invited to serve as a Science Fellow at the U.S. Embassy in Hanoi, Vietnam. He spent the fall of 2023 participating in an international collaboration to sample Vietnamese coal and coal combustion products and examine their potential as a source of critical elements. Samples obtained in this project are the subject of his ongoing investigation.
Professional Experience
2023 - present, Scientist Emeritus, USGS Geology, Energy, & Minerals Science Center, Reston, VA
1996 - 2022, Research Geologist, USGS Eastern Energy Resources Science Center, Reston, VA, and USGS Geology, Energy, & Minerals Science Center, Reston, VA.
1990 - 1996, Assistant Professor, Department of Geology, University of Nebraska-Lincoln
1989 - 1990, Postdoctoral Research Associate, Department of Applied Science, Brookhaven National Laboratory, Upton, NY
1982 - 1983, Geologist, The University of Texas at Austin, Bureau of Economic Geology, Austin, TX
1980 - 1981, Geologist/Technical Editor, USGS Office of International Geology, Reston, VA
Education and Certifications
Ph.D. Geochemistry, Department of Earth and Space Sciences, Stony Brook University, 1989
M.S. Geology, Department of Geosciences, University of Massachusetts at Amherst, 1980
B.A. Geology, Department of Geology, Franklin and Marshall College, 1977
Science and Products
Rare Earth Elements in coal fly ash and their potential recovery Rare Earth Elements in coal fly ash and their potential recovery
Energy-related rare earth element sources Energy-related rare earth element sources
Geochemical data for Illinois Basin coal samples, 2015–2018 Geochemical data for Illinois Basin coal samples, 2015–2018
Rare earth elements in coal and coal fly ash Rare earth elements in coal and coal fly ash
Topics in coal geochemistry—Short course Topics in coal geochemistry—Short course
Mercury in U.S. coal—Priorities for new U.S. Geological Survey studies Mercury in U.S. coal—Priorities for new U.S. Geological Survey studies
Mercury and trace element distribution in density separates of a South African Highveld (#4) coal: Implications for mercury reduction and preparation of export coal Mercury and trace element distribution in density separates of a South African Highveld (#4) coal: Implications for mercury reduction and preparation of export coal
Collaborative Studies for Mercury Characterization in Coal and Coal Combustion Products, Republic of South Africa Collaborative Studies for Mercury Characterization in Coal and Coal Combustion Products, Republic of South Africa
Trace elements in coal ash Trace elements in coal ash
Size distribution of rare earth elements in coal ash Size distribution of rare earth elements in coal ash
Atmospheric particulate matter in proximity to mountaintop coal mines: Sources and potential environmental and human health impacts Atmospheric particulate matter in proximity to mountaintop coal mines: Sources and potential environmental and human health impacts
Mercury and halogens in coal Mercury and halogens in coal
Non-USGS Publications**
Deonarine, A., Kolker, A., Doughten, M., Bailoo, J.D., and Holland, J.T., Arsenic speciation in bituminous coal fly ash and transformations in response to redox conditions: Submitted to Environmental Science and Technology.
**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.
Evolving Utilization of Solid Energy Fuels (EUSEF)
Geochemistry of Energy Fuels Project
Byproducts of Energy Fuels
Trace Elements in Energy Fuels
Geochemical Data for Coal Wastes from Historic Anthracite Coal Mining in Pennsylvania, 2024 Geochemical Data for Coal Wastes from Historic Anthracite Coal Mining in Pennsylvania, 2024
Geochemical Data for Coal Wastes from Bituminous Coal Mining in Pennsylvania, 2022 Geochemical Data for Coal Wastes from Bituminous Coal Mining in Pennsylvania, 2022
Geochemical Data for Illinois Basin Coal Samples, 2015-2018 (ver. 1.1, March 2021) Geochemical Data for Illinois Basin Coal Samples, 2015-2018 (ver. 1.1, March 2021)
Arsenic in stream sediments of northern Alabama Arsenic in stream sediments of northern Alabama
Science and Products
Rare Earth Elements in coal fly ash and their potential recovery Rare Earth Elements in coal fly ash and their potential recovery
Energy-related rare earth element sources Energy-related rare earth element sources
Geochemical data for Illinois Basin coal samples, 2015–2018 Geochemical data for Illinois Basin coal samples, 2015–2018
Rare earth elements in coal and coal fly ash Rare earth elements in coal and coal fly ash
Topics in coal geochemistry—Short course Topics in coal geochemistry—Short course
Mercury in U.S. coal—Priorities for new U.S. Geological Survey studies Mercury in U.S. coal—Priorities for new U.S. Geological Survey studies
Mercury and trace element distribution in density separates of a South African Highveld (#4) coal: Implications for mercury reduction and preparation of export coal Mercury and trace element distribution in density separates of a South African Highveld (#4) coal: Implications for mercury reduction and preparation of export coal
Collaborative Studies for Mercury Characterization in Coal and Coal Combustion Products, Republic of South Africa Collaborative Studies for Mercury Characterization in Coal and Coal Combustion Products, Republic of South Africa
Trace elements in coal ash Trace elements in coal ash
Size distribution of rare earth elements in coal ash Size distribution of rare earth elements in coal ash
Atmospheric particulate matter in proximity to mountaintop coal mines: Sources and potential environmental and human health impacts Atmospheric particulate matter in proximity to mountaintop coal mines: Sources and potential environmental and human health impacts
Mercury and halogens in coal Mercury and halogens in coal
Non-USGS Publications**
Deonarine, A., Kolker, A., Doughten, M., Bailoo, J.D., and Holland, J.T., Arsenic speciation in bituminous coal fly ash and transformations in response to redox conditions: Submitted to Environmental Science and Technology.
**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.