Skip to main content
U.S. flag

An official website of the United States government

Amy Gartman, PhD

I lead the USGS Global Marine Minerals project, which you can learn more about here. My work focuses on the geochemistry of marine minerals including all aspects of water-rock interactions such as precipitation, alteration, and the role of nanoparticles in mineral accumulation. 

Science and Products

link
Collage of black nodules or rocks of varying sizes and shapes, each 1-7 inches wide, broken in half to show their cores.

Global Marine Mineral Resources

Researching seafloor mineral resources that occur within the U.S. Exclusive Economic Zone and areas beyond national jurisdictions.
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, Deep Sea Exploration, Mapping and Characterization
link

Global Marine Mineral Resources

Researching seafloor mineral resources that occur within the U.S. Exclusive Economic Zone and areas beyond national jurisdictions.
Learn More

Prospective regions for marine minerals on the Alaska Outer Continental Shelf

This shapefile is of prospective regional outlines of where marine minerals may occur on the Alaska Outer Continental Shelf (OCS). Polygons were hand digitized based on a U.S. Geological Survey (USGS) data review that considers the state of knowledge regarding marine mineral occurrences within the Alaska OCS. This data release is a companion to the USGS Professional Paper, Gartman and others, 2022
By
Pacific Coastal and Marine Science Center

Computed tomography (CT) scans, photographs, X-ray fluorescence (XRF) scans, geochemistry, X-ray diffraction (XRD), and gamma-ray bulk density data of push cores from Loki's Castle and Favne vent fields, Mohns Ridge

This data release contains computed tomography (CT) scans, photographs, X-ray fluorescence (XRF) scans, geochemical data, X-ray diffractograms (XRD), and gamma-ray bulk density of push cores and sediment subsamples from those cores collected in 2018 and 2019 from Loki’s and Favne Vent Fields, Mohns Ridge, part of the Arctic Mid-Atlantic Ridge. For the geochemical section of the release, data inclu
By
Pacific Coastal and Marine Science Center

Marine mineral geochemical data - Part One: Pacific Ocean USGS-affiliated historical data

This data release compiles element composition data for more than 600 deep-ocean mineral samples from more than 25 research cruises in the Pacific Ocean since 1979 that involved USGS researchers. Deep-ocean mineral sample types encompassed in this data release include ferromanganese crusts, manganese nodules, phosphorites, and hydrothermal minerals. This data release is comprised of both unpublish
By
Pacific Coastal and Marine Science Center

Measurements of zinc, oxygen, and pH, from sphalerite and ZnS oxidation in seawater

This data release presents the concentration of zinc, oxygen, pH, temperature, and the time point at which measurements were taken for experimental oxidation work regarding zinc and copper sulfide minerals. These data accompany the following publication: Gartman, A., Whisman, S.P., and Hein, J.R., 2020, Interactive oxidation of sphalerite and covellite in seawater: implications for seafloor
By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center
Black smoke billows out of a crusty vent on the ocean floor.
Mineral-laden water emerging from a hydrothermal vent
Mineral-laden water emerging from a hydrothermal vent
Black smoke billows out of a crusty vent on the ocean floor.

Mineral-laden water emerging from a hydrothermal vent

Mineral-laden water emerging from a hydrothermal vent

Mineral-laden water emerging from a hydrothermal vent on the Niua underwater volcano in the Lau Basin, southwest Pacific Ocean. As the water cools, minerals precipitate to form tower-like “chimneys.” Image taken during 2016 cruise “Virtual Vents.”  

By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center
Black smoke billows out of a crusty vent on the ocean floor.

Mineral-laden water emerging from a hydrothermal vent

Mineral-laden water emerging from a hydrothermal vent

Mineral-laden water emerging from a hydrothermal vent on the Niua underwater volcano in the Lau Basin, southwest Pacific Ocean. As the water cools, minerals precipitate to form tower-like “chimneys.” Image taken during 2016 cruise “Virtual Vents.”  

By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center
Filter Total Items: 17

Hydrothermal plume fallout, mass wasting, and volcanic eruptions contribute to sediments at Loki’s Castle vent field, Mohns Ridge

Sediments surrounding hydrothermal vents are important transition spaces between hydrothermal and pelagic environments. These sediments accumulate through diverse processes that include water column plume fallout, volcanic ash deposition, and mass wasting of hydrothermal chimneys and mounds superimposed upon background sedimentation which may originate from pelagic, terrestrial, and volcanic sourc
Authors
Amy Gartman, Denise M Payan, Manda Viola Au, Eoghan P. Reeves, John Jamieson, Caroline Gini, Desiree Roerdink
By
Pacific Coastal and Marine Science Center

Marine minerals in Alaska — A review of coastal and deep-ocean regions

Minerals occurring in marine environments span the globe and encompass a broad range of mineral categories, forming within varied geologic and oceanographic settings. They occur in coastal regions, either from the continuation or mechanical reworking of terrestrial mineralization, as well as in the deep ocean, from diagenetic, hydrogenetic, and hydrothermal processes. The oceans cover most of the

Authors
Amy Gartman, Kira Mizell, Douglas C. Kreiner
By
Ecosystems Mission Area, Coastal and Marine Hazards and Resources Program, Alaska Science Center, Pacific Coastal and Marine Science Center, Marine Minerals Laboratory

Estimates of metals contained in abyssal manganese nodules and ferromanganese crusts in the global ocean based on regional variations and genetic types of nodules

Deep-ocean ferromanganese crusts and manganese nodules are important marine repositories for global metals. Interest in these minerals as potential resources has led to detailed sampling in many regions of the global ocean, allowing for updated estimates of their global extent. Here, we present global estimates of total tonnage as well as contained metal concentrations and tonnages for ferromangan
Authors
Kira Mizell, James R. Hein, Manda Viola Au, Amy Gartman
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, Marine Minerals Laboratory, Deep Sea Exploration, Mapping and Characterization

Extent of impact of deep-sea nodule mining midwater plumes is influenced by sediment loading, turbulence and thresholds

Deep-sea polymetallic nodule mining research activity has substantially increased in recent years, but the expected level of environmental impact is still being established. One environmental concern is the discharge of a sediment plume into the midwater column. We performed a dedicated field study using sediment from the Clarion Clipperton Fracture Zone. The plume was monitored and tracked using
Authors
Carlos Munoz-Royo, Thomas Peacock, Matthew Alford, Jerome Smith, Arnaud Le Boyer, Chinmay Kulkarni, Pierre Lermusiaux, Patrick Haley, C Mirabito, Dayang Wang, Eric Adams, Raphael Ouillon, Alexander Breugem, Boudewijn Decrop, Thijs Lanckreit, Rohit Supekar, Andrew Rzeznik, Amy Gartman, Se-Jong Ju
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, Deep Sea Exploration, Mapping and Characterization

Carbonate-hosted microbial communities are prolific and pervasive methane oxidizers at geologically diverse marine methane seep sites

At marine methane seeps, vast quantities of methane move through the shallow subseafloor, where it is largely consumed by microbial communities. This process plays an important role in global methane dynamics, but we have yet to identify all of the methane sinks in the deep sea. Here, we conducted a continental-scale survey of seven geologically diverse seafloor seeps and found that carbonate rock
Authors
Jeffrey J. Marlow, Daniel Hoer, Sean Jungbluth, Linda Reynard, Amy Gartman, Marko S. Chavez, Mohamed Y. El-Naggar, Noreen Tuross, Victoria Orphan, Peter R. Girguis
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

America’s offshore critical mineral wealth

No abstract available.
Authors
,
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, Deep Sea Exploration, Mapping and Characterization

Sphalerite oxidation in seawater with covellite: Implications for seafloor massive sulfide deposits and mine waste

Metal sulfide minerals exist in several marine environments and are in thermodynamic disequilibrium with oxygenated seawater from the time of their formation. Oxidation is both ubiquitous and heterogeneous, as observational and experimental evidence demonstrates that sulfide minerals may oxidize completely on decadal timescales (hydrothermal plumes) or incompletely in billions of years (mineral de
Authors
Amy Gartman, Samantha P. Whisman, James R. Hein
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, Deep Sea Exploration, Mapping and Characterization

Research is needed to inform environmental management of hydrothermally inactive and extinct polymetallic sulfide (PMS) deposits

Polymetallic sulfide (PMS) deposits produced at hydrothermal vents in the deep sea are of potential interest to miners. Hydrothermally active sulfide ecosystems are valued for the extraordinary chemosynthetic communities that they support. Many countries, including Canada, Portugal, and the United States, protect vent ecosystems in their Exclusive Economic Zones. When hydrothermal activity ceases
Authors
CL Van Dover, Ana Colaco, PC Collins, P Croot, Anna Metaxas, BJ Murton, A Swaddling, R Boschen-Rose, J Carlsson, L Cuyvers, Toshio Fukushima, Amy Gartman, R. Kennedy, C Kriete, NC Mestre, T Molodtsova, A Myhrvold, E Pelleter, SO Popoola, P-Y Qian, J Sarrazin, R Sharma, YJ Suh, JB Sylvan, Chunhui Tao, Michal Tomczak, J Vermilye
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

Impacts of hydrothermal plume processes on oceanic metal cycles and transport

Chemical, physical and biological processes in hydrothermal plumes control the flux of elements from hydrothermal vents to the global oceans. The timescales of these processes range from less than a second, as the hydrothermal fluid mixes with seawater at the seafloor, to decades, as the plume disperses over thousands of kilometers. Integrating hydrothermal geochemistry throughout the lifetime of
Authors
Amy Gartman, Alyssa J. Findlay
By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

Defining active, inactive, and extinct seafloor massive sulfide deposits

Hydrothermal activity results in the formation of hydrothermal mineral deposits, including seafloor massive sulfide deposits, at oceanic spreading ridges, arcs, and back-arcs. As hydrothermal systems age, the mineral deposits eventually become severed from the heat source and fluid-flow pathways responsible for their formation and become extinct. The timescales and processes by which this cessatio
Authors
John W. Jamieson, Amy Gartman
By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

Mapping metabolic activity at single cell resolution in intact volcanic fumarole soil

Interactions among microorganisms and their mineralogical substrates govern the structure, function, and emergent properties of microbial communities. These interactions are predicated on spatial relationships, which dictate metabolite exchange and access to key substrates. To quantitatively assess links between spatial relationships and metabolic activity, this study presents a novel approach to
Authors
Jeffrey J. Marlow, Isabella Colocci, Sean Jungbluth, Nils Moritz Weber, Amy Gartman, Jens Kallmeyer
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

The role of nanoparticles in mediating element deposition and transport at hydrothermal vents

Precipitation processes in hydrothermal fluids exert a primary control on the eventual distribution of elements, whether that sink is in the subseafloor, hydrothermal chimneys, near-field metalliferous sediments, or more distal in the ocean basin. Recent studies demonstrating abundant nanoparticles in hydrothermal fluids raise questions as to the importance of these nanoparticles relative to macro
Authors
Amy Gartman, Alyssa J. Findlay, Mark D. Hannington, Dieter Garbe-Schönberg, John W. Jamieson, Tom Kwasnitschka
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center
Arctic Mid-Ocean Ridge Sediment Cores Shed Light on Past Hydrothermal Activity

Arctic Mid-Ocean Ridge Sediment Cores Shed Light on Past Hydrothermal Activity

In new research led by USGS, scientists analyzed cores collected from Loki's Castle vent field, a high-temperature hydrothermal system deep beneath...

Read Article
USGS Researchers Return to Eastern Galapágos Spreading Center

USGS Researchers Return to Eastern Galapágos Spreading Center

A research team including USGS scientists returned to the Eastern Galapágos Spreading Center to investigate its deep-sea hydrothermal vents, where...

Read Article
Critical Minerals in the EEZ

Critical Minerals in the EEZ

For centuries, people have crossed oceans in search of valuable minerals. In recent times, though, increasing attention has been paid to the oceans...

Read Article
Two New Research Oceanographers at the Pacific Coastal and Marine Science Center in Santa Cruz, California

Two New Research Oceanographers at the Pacific Coastal and Marine Science Center in Santa Cruz, California

Meet the new researchers at the USGS Pacific Coastal and Marine Science Center in Santa Cruz, California

Read Article
How Will Underwater Mining Affect the Deep Ocean? Growing a Research Community to Find Out

How Will Underwater Mining Affect the Deep Ocean? Growing a Research Community to Find Out

USGS oceanographer Amy Gartman and team seek to understand how and where mineral-rich deposits form in the ocean, and what effects mining them could...

Read Article
USGS oceanographer part of U.S. delegation to International Seabed Authority

USGS oceanographer part of U.S. delegation to International Seabed Authority

Oceanographer Amy Gartman joined two members of the U.S. State Department at the 24th session of the International Seabed Authority, the organization...

Read Article
First observation of gold particles in hot hydrothermal fluids

First observation of gold particles in hot hydrothermal fluids

For the first time, scientists have found gold particles in boiling fluids from a hydrothermal vent.

Read Article

Science and Products