The familiar saying “good things come in small packages” holds especially true for deep-sea biological communities at hydrothermal vents, including those at Escanaba Trough, a seafloor spreading center located almost 200 miles off the northern California coast.
Mineral-laden water emerging from a hydrothermal vent
Hydrothermal vent chimney from the southwest Pacific Ocean
Ferromanganese crust from the south Pacific Ocean
Ferromanganese nodule being sampled from the North Atlantic seafloor
The Global Marine Mineral Resources project studies deep ocean minerals that occur within the U.S. Exclusive Economic Zone and areas beyond national jurisdictions. Our research concerns the setting, genesis, and metal enrichment processes of mineral occurrences, the relationship between marine minerals related and deep-sea biota, and the potential geochemical footprint of any seafloor mining. We aim to provide stakeholders with the best available science regarding potential resources and environmental impacts associated with accessing those resources.
Research Overview
Sources/Usage: Public Domain. View Media Details
The Global Marine Mineral Resources project objectives include:
-
Geochemical characterization of mineral samples, including mineralogy and metal concentrations, and their variability regionally and globally
-
Correlation of oceanographic and geographic parameters with mineralogy and metal content to elucidate the controls on mineral formation and element enrichment, and to map prospective mineral regions within the global ocean
-
Investigation of mineral stability and metal mobility with exposure to seawater over time through experimental geochemistry to constrain geochemical effects of mineral disturbance
-
Collaboration with biologists to determine associations between minerals and the biological communities which inhabit and surround them
Our findings inform stakeholders, including the public, government, industry, academics and NGOs, about mineral wealth and its environmental setting within the vast offshore territory of the U.S. and helps them determine which regions and deposits may warrant further research.
Ferromanganese Crusts
Ferromanganese Crusts
Seafloor pavements and encrusted rocks are known as ferromanganese crusts (also called cobalt-rich crusts). These crusts grow very slowly, at several millimeters per million years, and precipitate onto exposed rock surfaces throughout the global ocean—they do not form where sediment blankets the seafloor. In the oldest parts of the seafloor in the northwest Pacific Ocean, some crusts have been forming for over 70 million years and can be over 20 centimeters thick. Crusts act as a sponge of sorts, adsorbing metals and other elements from seawater over these long periods of time, and are especially enriched in cobalt, manganese, rare metals such as tellurium, precious metals such as platinum, and rare earth elements.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Manganese Nodules
Manganese Nodules
Over millions of years, spheroidal rocks called manganese nodules (or polymetallic nodules) form atop sediment covering the abyssal plains of the global ocean. These nodules form by the accretion of iron and manganese oxides around a tiny nucleus, such as a large grain of sand, a shark tooth, or older nodule fragment. Manganese nodules are usually golf-ball to baseball size and grow very slowly like ferromanganese crusts if they acquire all their metals directly from seawater, or they grow faster if they also acquire their metals from the pore-waters of the sediment on which they sit. Nodules are currently of great interest for mining due to high concentrations of manganese, nickel, copper, and sometimes lithium, as well as the straightforward nature of quantifying their distribution and density.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Seafloor Massive Sulfides
Seafloor Massive Sulfides
Also known as polymetallic sulfides, seafloor massive sulfides form at hydrothermal vents when seawater penetrates the ocean’s crust and becomes heated and chemically modified through interaction with crustal rocks and, sometimes, by input of magmatic fluids. The hot hydrothermal fluids then rise back toward the seafloor and precipitate minerals as they cool along flow paths and upon mixing with seawater.
Sources/Usage: Public Domain. View Media Details
A wide variety of minerals form through hydrothermal activity, but seafloor massive sulfides are formed from reduced sulfur and may be enriched in copper, zinc, iron, gold, and silver. Hydrothermal vents exist along mid-ocean ridge spreading centers, extensional systems associated with subduction zones, volcanoes, and intraplate hotspots. Yet, seafloor massive sulfides likely extend beyond these active hydrothermal zones. We know the minerals persist after removal from the heat source because of the presence of volcanogenic massive sulfide deposits on land.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Marine Phosphorites
Marine Phosphorites
Marine phosphorites primarily occur along continental margins where upwelling of cold, nutrient-rich, deep water is strong. These areas include the Peru-Chile margin, on plateaus such as Chatham Rise offshore New Zealand, and the Blake-Bahamas Plateau off the southeast United States; but they can also form on seamounts where ferromanganese crusts grow. Phosphorites form when abundant phosphate in seawater replaces carbonate in calcareous sediments or precipitates in situ as apatite to form hardgrounds, phosphatic nodules, or cements in breccias of multiple rock types. Marine phosphorites are sources of phosphate used as fertilizer for agriculture and phosphoric acid in the food industry. Phosphorites can also contain high concentrations of valuable, heavy, rare-earth elements that may be economically recoverable and can contain up to 4% fluorine.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Marine Mining Context
The oceans cover nearly three quarters of the surface of the earth, and in the U.S., the area of seafloor comprising the Exclusive Economic Zone is greater than the land area on shore. This enormous ocean realm hosts many types of minerals that differ from those occurring terrestrially. Ferromanganese crusts, manganese nodules, phosphorites, and hydrothermal vent deposits, which occur from the Arctic to the Antarctic, are enriched in many metals including those currently deemed societally critical. It is therefore important to understand these minerals and the role they may play as future mineral resources.
People around the world demand metals and mineral resources for many uses, including technology, electronics, and green energy infrastructure such as wind turbines and electric cars. Critical minerals are defined as those that are essential to the economic and national security of a nation but that have a supply-chain vulnerable to disruption. In 2022, the Department of the Interior released a list of 50 critical minerals, with the list to be reconsidered biannually. Across the USGS, research is underway to define and prioritize focus areas throughout the United States with resource potential for these 35 critical minerals. The Global Marine Mineral Resources project specifically informs the marine component.
To date, there is no mining of deep-sea minerals. In Areas Beyond National Jurisdiction, any marine mining is governed by the International Seabed Authority, which is currently drafting exploitation regulations. The Global Marine Mineral Resources project has provided scientific advice to the U.S. State Department and has served as a member of the U.S. delegation to the International Seabed Authority as an Observer Nation since 2007.
Sources/Usage: Public Domain. View Media Details
Below are other studies related to this project.
USGS Law of the Sea
The USGS Law of the Sea project helps to determine the outer limits of the extended continental shelf (ECS) of the United States. The ECS is that portion of the continental shelf beyond 200 nautical miles. It is an important maritime zone that holds many resources and vital habitats for marine life. Its size may exceed one million square kilometers, encompassing areas in the Arctic, Atlantic...
Resources: EXPRESS
Along the U.S. west coast, the Pacific Ocean, ocean floor, and winds above contain potentially vast energy and mineral resources. Developing these resources safely and wisely requires detailed information for each area of interest. One goal of EXPRESS is to inform ocean energy and mineral resource decisions.
Below are multimedia items associated with this project.
Escanaba Trough Expedition: Biological Communities
The familiar saying “good things come in small packages” holds especially true for deep-sea biological communities at hydrothermal vents, including those at Escanaba Trough, a seafloor spreading center located almost 200 miles off the northern California coast.
Escanaba Trough Expedition: Gravity Coring
Seafloor features such as sulfide mounds and chimneys are prominent evidence of hydrothermal activity. These features, whether active or dormant, are just the tip of the iceberg, so to speak; much of the “plumbing” of hydrothermal systems exists beneath the seafloor surface.
Seafloor features such as sulfide mounds and chimneys are prominent evidence of hydrothermal activity. These features, whether active or dormant, are just the tip of the iceberg, so to speak; much of the “plumbing” of hydrothermal systems exists beneath the seafloor surface.
Escanaba Trough Expedition: Part 2
Critical to scientific operations aboard the Escanaba Trough expedition is the submersible robots Sentry and Jason. Owned and operated by the Woods Hole Oceanographic Institute (WHOI), these robots allow researchers to observe seafloor features and collect data from depths seldom visited by humans.
Critical to scientific operations aboard the Escanaba Trough expedition is the submersible robots Sentry and Jason. Owned and operated by the Woods Hole Oceanographic Institute (WHOI), these robots allow researchers to observe seafloor features and collect data from depths seldom visited by humans.
Escanaba Trough Expedition: Part 3
For scientists aboard the Escanaba Trough expedition, obtaining sediment cores or deep-sea biological and geological samples after a Jason dive is only the beginning.
For scientists aboard the Escanaba Trough expedition, obtaining sediment cores or deep-sea biological and geological samples after a Jason dive is only the beginning.
Escanaba Trough Expedition: Introduction
Embarking on a three-week deep-sea research expedition requires a lot of preparation. For this expedition to Escanaba Trough, U.S. Geological Survey scientists and partners spend the first few days in port, building their laboratory space aboard the research vessel Thomas G. Thompson.
Embarking on a three-week deep-sea research expedition requires a lot of preparation. For this expedition to Escanaba Trough, U.S. Geological Survey scientists and partners spend the first few days in port, building their laboratory space aboard the research vessel Thomas G. Thompson.
Climate Science Champions, Season 2: Kira Mizell, Research Oceanographer
Research Oceanographer Kira Mizell studies change in ocean chemistry by collecting marine minerals, looking for insights into past climate conditions and geologic history.
Research Oceanographer Kira Mizell studies change in ocean chemistry by collecting marine minerals, looking for insights into past climate conditions and geologic history.
Ferromanganese Nodules—2021 North Atlantic Stepping Stones Expedition
During a recent dive on the New England Seamount chain off the North Atlantic coast, researchers aboard the NOAA Ocean Exploration Expedition, North Atlantic Stepping Stones, discovered a marine geological feature known as a ferromanganese (Fe-Mn) nodule field in the saddle between two peaks of Gosnold Seamount.
During a recent dive on the New England Seamount chain off the North Atlantic coast, researchers aboard the NOAA Ocean Exploration Expedition, North Atlantic Stepping Stones, discovered a marine geological feature known as a ferromanganese (Fe-Mn) nodule field in the saddle between two peaks of Gosnold Seamount.
NOAA-USGS Stepping Stones 2021 Expedition
Join USGS researchers Jason Chaytor and Kira Mizell as they virtually participate in a NOAA Ocean Exploration expedition to the depths of the North Atlantic.
Join USGS researchers Jason Chaytor and Kira Mizell as they virtually participate in a NOAA Ocean Exploration expedition to the depths of the North Atlantic.
The Global Marine Mineral Resources project studies deep ocean minerals that occur within the U.S. Exclusive Economic Zone and areas beyond national jurisdictions. Our research concerns the setting, genesis, and metal enrichment processes of mineral occurrences, the relationship between marine minerals related and deep-sea biota, and the potential geochemical footprint of any seafloor mining. We aim to provide stakeholders with the best available science regarding potential resources and environmental impacts associated with accessing those resources.
Research Overview
Sources/Usage: Public Domain. View Media Details
The Global Marine Mineral Resources project objectives include:
-
Geochemical characterization of mineral samples, including mineralogy and metal concentrations, and their variability regionally and globally
-
Correlation of oceanographic and geographic parameters with mineralogy and metal content to elucidate the controls on mineral formation and element enrichment, and to map prospective mineral regions within the global ocean
-
Investigation of mineral stability and metal mobility with exposure to seawater over time through experimental geochemistry to constrain geochemical effects of mineral disturbance
-
Collaboration with biologists to determine associations between minerals and the biological communities which inhabit and surround them
Our findings inform stakeholders, including the public, government, industry, academics and NGOs, about mineral wealth and its environmental setting within the vast offshore territory of the U.S. and helps them determine which regions and deposits may warrant further research.
Ferromanganese Crusts
Ferromanganese Crusts
Seafloor pavements and encrusted rocks are known as ferromanganese crusts (also called cobalt-rich crusts). These crusts grow very slowly, at several millimeters per million years, and precipitate onto exposed rock surfaces throughout the global ocean—they do not form where sediment blankets the seafloor. In the oldest parts of the seafloor in the northwest Pacific Ocean, some crusts have been forming for over 70 million years and can be over 20 centimeters thick. Crusts act as a sponge of sorts, adsorbing metals and other elements from seawater over these long periods of time, and are especially enriched in cobalt, manganese, rare metals such as tellurium, precious metals such as platinum, and rare earth elements.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Manganese Nodules
Manganese Nodules
Over millions of years, spheroidal rocks called manganese nodules (or polymetallic nodules) form atop sediment covering the abyssal plains of the global ocean. These nodules form by the accretion of iron and manganese oxides around a tiny nucleus, such as a large grain of sand, a shark tooth, or older nodule fragment. Manganese nodules are usually golf-ball to baseball size and grow very slowly like ferromanganese crusts if they acquire all their metals directly from seawater, or they grow faster if they also acquire their metals from the pore-waters of the sediment on which they sit. Nodules are currently of great interest for mining due to high concentrations of manganese, nickel, copper, and sometimes lithium, as well as the straightforward nature of quantifying their distribution and density.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Seafloor Massive Sulfides
Seafloor Massive Sulfides
Also known as polymetallic sulfides, seafloor massive sulfides form at hydrothermal vents when seawater penetrates the ocean’s crust and becomes heated and chemically modified through interaction with crustal rocks and, sometimes, by input of magmatic fluids. The hot hydrothermal fluids then rise back toward the seafloor and precipitate minerals as they cool along flow paths and upon mixing with seawater.
Sources/Usage: Public Domain. View Media Details
A wide variety of minerals form through hydrothermal activity, but seafloor massive sulfides are formed from reduced sulfur and may be enriched in copper, zinc, iron, gold, and silver. Hydrothermal vents exist along mid-ocean ridge spreading centers, extensional systems associated with subduction zones, volcanoes, and intraplate hotspots. Yet, seafloor massive sulfides likely extend beyond these active hydrothermal zones. We know the minerals persist after removal from the heat source because of the presence of volcanogenic massive sulfide deposits on land.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Marine Phosphorites
Marine Phosphorites
Marine phosphorites primarily occur along continental margins where upwelling of cold, nutrient-rich, deep water is strong. These areas include the Peru-Chile margin, on plateaus such as Chatham Rise offshore New Zealand, and the Blake-Bahamas Plateau off the southeast United States; but they can also form on seamounts where ferromanganese crusts grow. Phosphorites form when abundant phosphate in seawater replaces carbonate in calcareous sediments or precipitates in situ as apatite to form hardgrounds, phosphatic nodules, or cements in breccias of multiple rock types. Marine phosphorites are sources of phosphate used as fertilizer for agriculture and phosphoric acid in the food industry. Phosphorites can also contain high concentrations of valuable, heavy, rare-earth elements that may be economically recoverable and can contain up to 4% fluorine.
Sources/Usage: Public Domain. View Media Details
Sources/Usage: Public Domain. View Media Details
Marine Mining Context
The oceans cover nearly three quarters of the surface of the earth, and in the U.S., the area of seafloor comprising the Exclusive Economic Zone is greater than the land area on shore. This enormous ocean realm hosts many types of minerals that differ from those occurring terrestrially. Ferromanganese crusts, manganese nodules, phosphorites, and hydrothermal vent deposits, which occur from the Arctic to the Antarctic, are enriched in many metals including those currently deemed societally critical. It is therefore important to understand these minerals and the role they may play as future mineral resources.
People around the world demand metals and mineral resources for many uses, including technology, electronics, and green energy infrastructure such as wind turbines and electric cars. Critical minerals are defined as those that are essential to the economic and national security of a nation but that have a supply-chain vulnerable to disruption. In 2022, the Department of the Interior released a list of 50 critical minerals, with the list to be reconsidered biannually. Across the USGS, research is underway to define and prioritize focus areas throughout the United States with resource potential for these 35 critical minerals. The Global Marine Mineral Resources project specifically informs the marine component.
To date, there is no mining of deep-sea minerals. In Areas Beyond National Jurisdiction, any marine mining is governed by the International Seabed Authority, which is currently drafting exploitation regulations. The Global Marine Mineral Resources project has provided scientific advice to the U.S. State Department and has served as a member of the U.S. delegation to the International Seabed Authority as an Observer Nation since 2007.
Sources/Usage: Public Domain. View Media Details
Below are other studies related to this project.
USGS Law of the Sea
The USGS Law of the Sea project helps to determine the outer limits of the extended continental shelf (ECS) of the United States. The ECS is that portion of the continental shelf beyond 200 nautical miles. It is an important maritime zone that holds many resources and vital habitats for marine life. Its size may exceed one million square kilometers, encompassing areas in the Arctic, Atlantic...
Resources: EXPRESS
Along the U.S. west coast, the Pacific Ocean, ocean floor, and winds above contain potentially vast energy and mineral resources. Developing these resources safely and wisely requires detailed information for each area of interest. One goal of EXPRESS is to inform ocean energy and mineral resource decisions.
Below are multimedia items associated with this project.
Escanaba Trough Expedition: Biological Communities
The familiar saying “good things come in small packages” holds especially true for deep-sea biological communities at hydrothermal vents, including those at Escanaba Trough, a seafloor spreading center located almost 200 miles off the northern California coast.
The familiar saying “good things come in small packages” holds especially true for deep-sea biological communities at hydrothermal vents, including those at Escanaba Trough, a seafloor spreading center located almost 200 miles off the northern California coast.
Escanaba Trough Expedition: Gravity Coring
Seafloor features such as sulfide mounds and chimneys are prominent evidence of hydrothermal activity. These features, whether active or dormant, are just the tip of the iceberg, so to speak; much of the “plumbing” of hydrothermal systems exists beneath the seafloor surface.
Seafloor features such as sulfide mounds and chimneys are prominent evidence of hydrothermal activity. These features, whether active or dormant, are just the tip of the iceberg, so to speak; much of the “plumbing” of hydrothermal systems exists beneath the seafloor surface.
Escanaba Trough Expedition: Part 2
Critical to scientific operations aboard the Escanaba Trough expedition is the submersible robots Sentry and Jason. Owned and operated by the Woods Hole Oceanographic Institute (WHOI), these robots allow researchers to observe seafloor features and collect data from depths seldom visited by humans.
Critical to scientific operations aboard the Escanaba Trough expedition is the submersible robots Sentry and Jason. Owned and operated by the Woods Hole Oceanographic Institute (WHOI), these robots allow researchers to observe seafloor features and collect data from depths seldom visited by humans.
Escanaba Trough Expedition: Part 3
For scientists aboard the Escanaba Trough expedition, obtaining sediment cores or deep-sea biological and geological samples after a Jason dive is only the beginning.
For scientists aboard the Escanaba Trough expedition, obtaining sediment cores or deep-sea biological and geological samples after a Jason dive is only the beginning.
Escanaba Trough Expedition: Introduction
Embarking on a three-week deep-sea research expedition requires a lot of preparation. For this expedition to Escanaba Trough, U.S. Geological Survey scientists and partners spend the first few days in port, building their laboratory space aboard the research vessel Thomas G. Thompson.
Embarking on a three-week deep-sea research expedition requires a lot of preparation. For this expedition to Escanaba Trough, U.S. Geological Survey scientists and partners spend the first few days in port, building their laboratory space aboard the research vessel Thomas G. Thompson.
Climate Science Champions, Season 2: Kira Mizell, Research Oceanographer
Research Oceanographer Kira Mizell studies change in ocean chemistry by collecting marine minerals, looking for insights into past climate conditions and geologic history.
Research Oceanographer Kira Mizell studies change in ocean chemistry by collecting marine minerals, looking for insights into past climate conditions and geologic history.
Ferromanganese Nodules—2021 North Atlantic Stepping Stones Expedition
During a recent dive on the New England Seamount chain off the North Atlantic coast, researchers aboard the NOAA Ocean Exploration Expedition, North Atlantic Stepping Stones, discovered a marine geological feature known as a ferromanganese (Fe-Mn) nodule field in the saddle between two peaks of Gosnold Seamount.
During a recent dive on the New England Seamount chain off the North Atlantic coast, researchers aboard the NOAA Ocean Exploration Expedition, North Atlantic Stepping Stones, discovered a marine geological feature known as a ferromanganese (Fe-Mn) nodule field in the saddle between two peaks of Gosnold Seamount.
NOAA-USGS Stepping Stones 2021 Expedition
Join USGS researchers Jason Chaytor and Kira Mizell as they virtually participate in a NOAA Ocean Exploration expedition to the depths of the North Atlantic.
Join USGS researchers Jason Chaytor and Kira Mizell as they virtually participate in a NOAA Ocean Exploration expedition to the depths of the North Atlantic.