About

Joshua Feinberg is a professor in the Department of Earth and Environmental Sciences at the University of Minnesota Twin Cities. His research employs a combination of geophysical approaches, such as rock magnetism, paleomagnetism, and gravity, alongside material characterization techniques including scanning and transmission electron microscopy, scanning force microscopy, and X-ray diffraction. These methods enable his group to critically examine a broad range of scientific problems, collaborating with specialists from disciplines such as geosciences, anthropology, soil science, planetary geology, material sciences, physics, chemistry, and biology. His research aims to understand the fine details of processes operating on various scales, from global and tectonic to outcrop and nanometer levels. Feinberg's educational background includes a PhD from the University of California, Berkeley, earned in 2005. He currently teaches courses in mineralogy, natural hazards and disasters, and geomagnetism and paleomagnetism. He is affiliated with the Institute for Rock Magnetism and offers undergraduate research opportunities in magnetism and groundwater monitoring.

Research topics

• Physics
• Geology
• Materials science
• Astrobiology
• Geography
• Geophysics
• Paleontology
• Condensed matter physics
• Archaeology
• Mineralogy
• Optics
• Mathematics

Selected publications

• Diverse <i>Sulfuriferula</i> spp. from sulfide mineral weathering environments oxidize ferrous iron and reduced inorganic sulfur compounds

  Applied and Environmental Microbiology · 2025-06-05 · 1 citations

  articleOpen access

  ABSTRACT Microorganisms are important catalysts for the oxidation of reduced inorganic sulfur compounds. One environmentally important source of reduced sulfur is metal sulfide minerals that occur in economic mineral deposits and mine waste. Previous research found that Sulfuriferula spp. were abundant and active in long-term weathering experiments with simulated waste rock and tailings from the Duluth Complex, Northern Minnesota. We, therefore, isolated several strains of Sulfuriferula spp. from these long-term experiments and characterized their metabolic and genomic properties to provide insight into microbe-mineral interactions and the microbial biogeochemistry in these and other moderately acidic to circumneutral environments. The Sulfuriferula strains are all obligate chemolithoautotrophs capable of oxidizing inorganic sulfur compounds and ferrous iron. The strains grew over different pH ranges, but all grew between pH 4.5 and 7, matching the weathering conditions of the Duluth Complex rocks. All strains grew on the iron-sulfide mineral pyrrhotite (Fe 1 − x S, 0 &lt; x &lt; 0.125) as the sole energy source, as well as hydrogen sulfide and thiosulfate, which are products of sulfide mineral breakdown. Despite their metabolic similarities, each strain encodes a distinct pathway for the oxidation of reduced inorganic sulfur compounds as well as differences in nitrogen metabolism that reveal diverse genomic capabilities among the group. Our results show that Sulfuriferula spp. are primary producers that likely play a role in sulfide mineral breakdown in moderately acidic to circumneutral mine waste, and the metabolic diversity within the genus may explain their success in sulfide mineral-rich and other sulfidic environments. IMPORTANCE Metal sulfide minerals, such as pyrite and pyrrhotite, are one of the main sources of reduced sulfur in the global sulfur cycle. The chemolithotrophic microorganisms that break down these minerals in natural and engineered settings are catalysts for biogeochemical sulfur cycling and have important applications in biotechnological processes such as biomining and bioremediation. Sulfuriferula is a recently described genus of sulfur-oxidizing bacteria that are abundant primary producers in diverse terrestrial environments, including waste rock and tailings from metal mining operations. In this study, we explored the genomic and metabolic properties of new isolates from this genus, and the implications for their ecophysiology and biotechnological potential in ore and waste from economic mineral deposits.

  PublisherDOI

• Origin of hematite in a stalagmite from the Cer&amp;#226;mica Cave, Central Portugal

  2025-03-15

  preprintOpen accessCorresponding

  Magnetic particles trapped into speleothems usually originate from the soils capping the cave and are transported into the cave by dripwaters. However, authigenic magnetic particles may also precipitate under conditions likely to prevail during speleothem growth. Here we investigate the magnetic mineralogy of a stalagmite from the Cer&amp;#226;mica Cave, Central Portugal, characterized by brown to red calcite laminations. We also analyzed the host carbonate, the cave sediments, and the soils capping the cave. We measured concentration- and grain size-dependent magnetic proxies, including natural remanent magnetization, anhysteretic remanent magnetization, isothermal remanent magnetization, mass-specific magnetic susceptibility, FORC, and hysteresis curves. &amp;#160;Results show that magnetic and hematite are the main magnetic carriers in all samples. A gradual enrichment of hematite relative to magnetite is observed following the transportation path from the soils to the cave sediments up to the stalagmite. The higher contribution of hematite relative to magnetite in the speleothem may reflect the precipitation of authentic hematite during speleothem growth or the selective transport of finer particles from the soil to the cave.&amp;#160;&amp;#160;This project is funded by Portuguese Funda&amp;#231;&amp;#227;o para a Ci&amp;#234;ncia e Tecnologia, FCT, I.P./MCTES through national funds (PIDDAC): UID/50019/2025, UIDB/50019/2020 (https://doi.org/10.54499/UIDB/50019/2020), LA/P/0068/2020 (https://doi.org/10.54499/LA/P/0068/2020), and PTDC/CTA-GEO/0125/2021, and is part of the Ph.D. of Ana Raquel Bras (2024.03482.BD).

  PublisherDOI

• Establishing a Paleosol-based Magnetostratigraphic Framework for the Early Eocene in the Wind River Basin, WY, USA

  Abstracts with programs - Geological Society of America · 2025-01-01

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  PublisherDOI

• Clastic Sediments from Sarah Furnace Cave, Pennsylvania, Record Hydrologic and Landscape Evolution of the Appalachian Plateau

  Abstracts with programs - Geological Society of America · 2025-01-01

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  PublisherDOI

• The importance of clays in speleothem magnetic remanence acquisition

  Scientific Reports · 2025-07-02

  articleOpen access

  Speleothems are promising recorders of paleosecular variation of the Earth's magnetic field, but ambiguities remain about the physical processes active during remanence acquisition. Speleothems have been used to determine relative paleointensity using classical methods for sedimentary materials. We created artificial speleothems by precipitating a solution of ammonium dihydrogen phosphate mixed with varying ratios of magnetite and kaolinite clay. These experiments were carried out over a range of Earth-like field intensities ranging from 15 to 70 [Formula: see text], allowing us to determine the conditions that maximize field sensitivity. We find that our artificial speleothems are good recorders of direction except for samples grown at low applied field strengths ([Formula: see text]) with a high magnetite to clay ratios (1:4). At any given field strength, more clay resulted in lower alignment efficiencies. Field sensitivity, or the amount of variation in the alignment efficiencies over the range of applied field strengths, was maximized for an intermediate ratio of magnetite to clay and nonlinear for the range of experimental and model parameters tested. The mechanism of speleothem remanence acquisition can be described by a two-step process: flocculate moment alignment with the field and flocculate-substrate interactions (FSIs). These findings have important implications for speleothem relative paleointensity studies since the delivery of detrital material within drip waters varies over time, causing a speleothem's alignment efficiency to fluctuate.

  PublisherOA PDFDOI

• Expressing Gratitude to Reviewers: A Message From the Editors of Reviews of Geophysics for 2024

  Reviews of Geophysics · 2025-03-01

  articleOpen access

  Abstract On behalf of the authors and readers of Reviews of Geophysics (RoG), the American Geophysical Union, and the broader scientific community, the editors wish to wholeheartedly thank those who reviewed manuscripts for RoG in 2024.

  PublisherOA PDFDOI

• Automated Groundwater Monitoring in Twin Cities Aquifers Shows Anthropogenic Changes in Water Quality Measures

  Environmental and Engineering Geoscience · 2025-04-10 · 1 citations

  article

  ABSTRACT Monitoring groundwater quality and quantity is increasingly important as growing usage stresses many regional aquifers. Manual sampling provides high-quality data but is not scalable to the monitoring needs of multi-aquifer systems with large numbers of wells. This is the case in the Twin Cities Metropolitan Area of Minnesota. As a result, it is difficult to capture short-term, sub-annual variations in water quality in metropolitan areas using conventional manual sampling. Such short-term variations can help establish links between anthropogenic activities at the surface and their time-delayed expression in water quality at depth. We recommend an automated network of sensors be established in the region to monitor groundwater quality in real time. Here, we demonstrate the diagnostic ability of a pilot network of instrumented wells on the University of Minnesota campus that are within 1 km2 and screened in two different aquifers. In situ sensors have gathered more than 2 years of sub-hourly data on temperature, water elevation, and specific conductance. High-frequency measurements of these simple physical parameters from 2021 to 2023 resolved episodic fluctuations in chloride concentrations that range from less than 300 mg/L to more than 500 mg/L, the effects of transient pumping related to local construction de-watering on groundwater flow, and steadily increasing groundwater temperatures inside a major urban area ranging from 0.07 to 0.14°C/yr. This pilot demonstration of real-time groundwater monitoring is scalable in Minnesota by state agencies with statutory responsibility for groundwater quality.

  PublisherDOI

• Differentiating between salt-tectonic and paleoclimatic processes in Quaternary sedimentary records from the Fisher Valley basin, Utah

  Geological Society of America Bulletin · 2025-07-03

  article

  Abstract The Fisher Valley basin (FVB), located adjacent to the Onion Creek salt diapir, Paradox basin, Utah, USA, constitutes one of the thickest collections of Quaternary sediments within the Colorado Plateau. These sediments are important for constraining regional paleoclimate environments as well as recent tectonic movement of the Onion Creek salt diapir. Here, we combine magnetic susceptibility data with previously published age constraints (Bishop Tuff and Lava Creek B ash) into a cyclostratigraphic analysis of these sediments. We present a refined and astronomically tuned age model that demonstrates that deposition of the upper basin fill was between ca. 765 ka and 212 ± 8 ka. Correlating this chronologic model to environmental magnetic proxies, we show that from ca. 765 ka to ca. 535 ka, magnetic mineral assemblages deposited during glacials were characterized by generally finer grain sizes (elevated χARM/χlow) than during interglacials. These data are consistent with glacial periods being characterized by either wetter conditions amenable to pedogenesis, or drier conditions associated with increased concentrations of windblown dust. Interglacials are characterized by generally coarser magnetic grain sizes (lower χARM/χlow), consistent with periods of episodic alluvial and colluvial deposition in the FVB. At ca. 535 ka, χARM/χlow reach their lowest value (coarsest magnetic grain size) and then begin a progressive transition to higher values, consistent with a generally fining upward stratigraphic sequence throughout the rest of the section. This transition at ca. 535 ka coincides with a peak in sediment accumulation rate of ~19 cm/k.y. and is most plausibly linked to halokinetic activity of the nearby Onion Creek salt diapir. Thus, although sediments in the FVB appear to be sensitive to global climate patterns between 765 ka and ca. 535 ka, local tectonic processes appear to episodically obscure this sensitivity.

  PublisherDOI

• The Role of Microorganisms in Shaping Earth's Magnetic History

  Annual Review of Earth and Planetary Sciences · 2025-02-14 · 1 citations

  articleOpen access

  Geomagnetic methods allow us to explore the behavior of Earth's geodynamo, constrain Earth's composition and structure, and locate critical minerals and other resources essential for modern technologies and the energy transition. The magnetic properties of rocks and sediments are assumed to be stable and largely attributable to inorganic processes. This conventional view overlooks mounting evidence of microorganisms as key players in rock transformations and geological processes. Iron-bearing minerals are ubiquitous in most environments and are commonly used by microorganisms as electron donors and acceptors. Microorganisms modulate rock magnetic properties by creating, altering, and dissolving Fe-bearing minerals, potentially modifying the original magnetization, complicating interpretations of the magnetic record. This review provides an overview of biogenic pathways that modulate magnetic minerals and discusses common, yet underutilized, magnetic methods for capturing such behavior. Appreciating the influence of microbial activities on magnetic properties will improve our interpretations of Earth's geologic past and its elemental cycling. ▪ Microorganisms modulate rock magnetic properties, challenging traditional views of a geologically stable magnetic record formed solely by inorganic processes. ▪ Microbial iron cycling modulates magnetic properties modifying magnetic information recorded in rocks. ▪ Microbial processes may have impacted Earth's magnetic history more deeply than previously understood. ▪ Recognizing microbial contributions is critical for accurate interpretation of paleomagnetic and environmental magnetic records and could aid in the search for life on other planetary bodies.

  PublisherDOI

• Characterizing anthropogenic impacts and modification of soils to aid in interpreting shallow geophysics in archeology

  Abstracts with programs - Geological Society of America · 2025-01-01

  article1st authorCorresponding
  PublisherDOI

Recent grants

• Linking Rock Magnetic Properties to the Performance of Paleointensity Techniques

  NSF · $254k · 2009–2012

• Collaborative Proposal: The Effect of Dislocations on Magnetic Properties of Small Titanomagnetite Minerals

  NSF · $45k · 2008–2012

• Collaborative Research: Identification of magnetic sources in the upper mantle

  NSF · $45k · 2014–2015

• Collaborative Research: Paleomagnetic Analysis of Speleothems and High Precision Dating of Geomagnetic Records

  NSF · $269k · 2013–2017

• Collaborative Research: Morphology and Timing of the Reunion/Huckleberry Ridge Event(s)

  NSF · $143k · 2010–2014

Frequent coauthors

• Daniel Hernández Ruipérez

  Instituto de Física Fundamental

  58 shared

• Steven Duplij

  55 shared

• Paul R. Renne

  Berkeley Geochronology Center

  54 shared

• Omer Faruk Dayi

  Istanbul Technical University

  50 shared

• R. J. Harrison

  University of Cambridge

  35 shared

• G. R. Scott

  Berkeley Geochronology Center

  25 shared

• Rafal E. Dunin‐Borkowski

  23 shared

• Takeshi Kasama

  23 shared