Marine Minerals and Offshore Energy

Each of our nation’s offshore regions host different—yet potentially vast—energy and mineral resources. These resources range from deep-sea minerals, which include elements that are critical to industry and technological applications, to oil, gas, and gas hydrates. Developing offshore resources safely and wisely requires detailed information for each area of interest. 

Deep sea minerals

Sources/Usage: Public Domain.

Like minerals on land, deep-sea minerals occur in a wide variety of settings related to Earth’s geologic framework and history. Unlike minerals on land, however, deep-sea minerals are less accessible and sometimes poorly understood. USGS is part of a global effort to shed light on the characterization and distribution of these potentially valuable minerals.

Some deep-sea minerals are of potential economic interest due to their composition, which can include critical minerals such as the rare earth elements needed for manufacturing by the technology sector and beyond. USGS investigates how and where these minerals form, what conditions contribute to their growth, how long it takes for them to accumulate, and identify where other similar minerals might occur.

For example, massive sulfide occurrences, which include many important metallic elements, occur in specific regions of the seafloor, including offshore of northern California and Oregon. These mineral mounds and chimneys form when hot water from beneath the ocean floor vents and mixes with cold seawater, creating precipitates that may have high concentrations of copper, zinc, iron, gold, and silver. Sulfide occurrences are characteristic geologic features of volcanic arcs, back arcs, and spreading centers. Volcanic arcs form as a result of subduction zones, where one tectonic plate slides beneath another under great temperatures and pressures. Learn more about Marine Geology.

Understanding these geothermal and geochemical processes allows scientists to determine where deep sea minerals occur and at what rates they accumulate. By characterizing the benthic environment through tectonic fault mapping, seafloor mapping, and habitat classification, USGS assists in evaluating the structural integrity of proposed energy projects and the environmental impacts to seafloor habitats.

The USGS works with multiple partners responsible for decisions about extracting mineral resources from the seabed and provides the science needed to evaluate these resources and activities related to extracting them safely and sustainably.

Sources/Usage: Public Domain.