Geological Mapping Project Supports Critical Mineral Explorations, Enhances Public Safety in the Southeast
Titanium is one of 50 critical minerals essential to the U.S. economy and national security. More than 95% of titanium used in the U.S. during 2024 was imported from other countries, so finding domestic sources of titanium is important for the U.S. to be self-sufficient. Titanium’s high strength-to-weight ratio is crucial for components in airplanes, spacecraft, military armor, and medical implants. Most titanium ore is processed into titanium dioxide, a pigment used in various products like paints, plastics, toothpaste and sunscreen.
In addition to its potential in locating critical minerals, this project fills a critical public safety need by assessing areas for earthquake hazards.
Many older geologic maps of the southeastern U.S. do not provide the detail needed to identify possible geological hazards, including rare but severe earthquakes that endanger lives and infrastructure. Updated maps can improve geological understanding and knowledge on earthquake risks, helping local governments and emergency services better prepare for and mitigate the impacts of earthquakes. This improved understanding helps local and state governments maximize the effectiveness of building codes, emergency plans, and public awareness programs.
“At the heart of this mapping endeavor is a commitment to public safety,” said Carter. “The project will provide local agencies and policymakers with the knowledge needed to implement effective hazard mitigation strategies, which can help save lives, protect communities and reduce economic losses in the event of a future earthquake.”
At present, the research for the project is focused on the Fall Line in southeast Virginia, northeastern North Carolina, and central Georgia. Much of the work in Georgia is focused on Federal lands, including the Oconee National Forests and both the Piedmont and Bond Swamp National Wildlife Refuges.
During fieldwork, geologists traverse varied terrains to study rocks outcrops, topographic features, and soils while collecting samples for laboratory analysis. A key aspect of geologic mapping is laboratory work to determine the age of rocks and sediments. At USGS labs, various techniques are employed to achieve this, such as uranium-lead dating for zircon minerals, pollen analysis to determine sediment age, cosmogenic nuclide dating to measure sunlight exposure, and optically stimulated luminescence dating to find out when sands were last exposed to sunlight, which tells experts when the sands were buried.
This field and laboratory work also helps other parts of the USGS like the Earth Mapping Resources Initiative (Earth MRI), which collects geophysical, geologic, geochemical, and topographic data across all regions of the U.S. to enhance scientific understanding of the nation’s geology and mineral resources. Earth MRI airborne surveys aid geologic mapping by measuring rock characteristics that are not visible to the naked eye but can be matched to geologic features that span large regions, even in remote, rugged areas or areas covered by vegetation or water. This project and similar efforts by USGS and State geological survey partners provide essential ground-truth information to interpret the geophysical data and infer the bedrock geology and features such as faults that are concealed beneath younger soils and sediment.
