Darryl A. Hoppe
Darryl Hoppe is a Geologist with the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.
Professional Experience
2018 - Present: Geologist, U.S. Geological Survey, GEMSC, Reston, Virginia
2016 - 2018: Science Tech, Lynxnet LLC, Contractor to the U.S. Geological Survey
Science and Products
Filter Total Items: 16
Molecular speciation of Ge within sphalerite, hemimorphite, and quartz from mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A. Molecular speciation of Ge within sphalerite, hemimorphite, and quartz from mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A.
Oxidation state and bonding environment of Ge in minerals within mine waste from sampled historical waste piles from the Tar Creek Superfund Site, Oklahoma, U.S. were determined by linear combination fits from x-ray absorption near edge spectroscopy (XANES) analysis. Ge content in quartz within these wastes was determined using XANES edge steps, and Ge content in sphalerite was compared...
Elemental concentrations for bulk and size-fractionated mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A. Elemental concentrations for bulk and size-fractionated mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A.
Elemental concentrations for bulk and size-fractionated mine waste from sampled historical waste piles from the Tar Creek Superfund Site, Oklahoma, U.S. were determined after dissolution via acid digests or a sodium peroxide fusion. Elemental concentrations were determined for the leachate from a simulated rainwater leach of mine wastes. Data and methods reported are part of a research...
Electron microprobe analyses of sphalerite and hemimorphite from mine wastes from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A. Electron microprobe analyses of sphalerite and hemimorphite from mine wastes from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A.
Electron microprobe analyses of sphalerite (ZnS) and hemimorphite (Zn4Si2O7(OH)2·H2O) from sampled historical waste piles were conducted with a specific focus on germanium (Ge). In mine wastes at the Tar Creek Superfund Site, Oklahoma, USA, Ge is associated with ZnS (sphalerite) as expected, but weathering in the waste piles has led to a significant amount of Ge being incorporated into a...
Geochemical characterization, acid neutralization potential, and phosphate removal capacity of modern and legacy iron and steel slag from the Chicago-Gary area of Illinois and Indiana, USA Geochemical characterization, acid neutralization potential, and phosphate removal capacity of modern and legacy iron and steel slag from the Chicago-Gary area of Illinois and Indiana, USA
Steelmaking slag from near Chicago, USA, may be a viable option for treating phosphate-rich or acidic waters. Iron and steel slags from legacy and modern operations in the Chicago-Gary area of Illinois and Indiana, USA, are predominantly composed of Ca, Fe, and Si, with generally lesser amounts of Al, Mg, and Mn. Simulated weathering tests suggest that potentially deleterious elements...
Science and Products
Filter Total Items: 16
Molecular speciation of Ge within sphalerite, hemimorphite, and quartz from mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A. Molecular speciation of Ge within sphalerite, hemimorphite, and quartz from mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A.
Oxidation state and bonding environment of Ge in minerals within mine waste from sampled historical waste piles from the Tar Creek Superfund Site, Oklahoma, U.S. were determined by linear combination fits from x-ray absorption near edge spectroscopy (XANES) analysis. Ge content in quartz within these wastes was determined using XANES edge steps, and Ge content in sphalerite was compared...
Elemental concentrations for bulk and size-fractionated mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A. Elemental concentrations for bulk and size-fractionated mine waste from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A.
Elemental concentrations for bulk and size-fractionated mine waste from sampled historical waste piles from the Tar Creek Superfund Site, Oklahoma, U.S. were determined after dissolution via acid digests or a sodium peroxide fusion. Elemental concentrations were determined for the leachate from a simulated rainwater leach of mine wastes. Data and methods reported are part of a research...
Electron microprobe analyses of sphalerite and hemimorphite from mine wastes from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A. Electron microprobe analyses of sphalerite and hemimorphite from mine wastes from the Tar Creek Superfund Site, Tri-State Mining District, Oklahoma, U.S.A.
Electron microprobe analyses of sphalerite (ZnS) and hemimorphite (Zn4Si2O7(OH)2·H2O) from sampled historical waste piles were conducted with a specific focus on germanium (Ge). In mine wastes at the Tar Creek Superfund Site, Oklahoma, USA, Ge is associated with ZnS (sphalerite) as expected, but weathering in the waste piles has led to a significant amount of Ge being incorporated into a...
Geochemical characterization, acid neutralization potential, and phosphate removal capacity of modern and legacy iron and steel slag from the Chicago-Gary area of Illinois and Indiana, USA Geochemical characterization, acid neutralization potential, and phosphate removal capacity of modern and legacy iron and steel slag from the Chicago-Gary area of Illinois and Indiana, USA
Steelmaking slag from near Chicago, USA, may be a viable option for treating phosphate-rich or acidic waters. Iron and steel slags from legacy and modern operations in the Chicago-Gary area of Illinois and Indiana, USA, are predominantly composed of Ca, Fe, and Si, with generally lesser amounts of Al, Mg, and Mn. Simulated weathering tests suggest that potentially deleterious elements...