Isotope Geochemistry

The project seeks to better understand the mineral systems of the Boulder batholith and surrounding region in Montana using new airborne geophysical data in conjunction with geologic mapping.

Project objectives are to (1) develop innovative analytical techniques for isotope geochemistry and U-Pb geochronology using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and (2) apply these techniques to collaborative research projects of high priority to the Mineral Resources Program, including studies related to the formation of "critical mineral" deposits, and...

The objective of this study is to characterize the regional impact of legacy mining in the context of framework geology for the Salmon Mountains in central Idaho. This objective is addressed through three interrelated tasks: 1) framework geology, 2) watershed biogeochemical processes, and 3) characterization of trace metals in colloids (fine particles suspended in water).

The main goal of this project is to provide a science-based approach for screening legacy mine land (LML) sites for remediation and identifying watersheds where relatively low-cost restoration efforts may yield substantial improvements to stream water quality. We are combing analysis of multiple existing regional data coverages with focused field studies to develop a protocol that land managers...

The project objective is to determine the processes responsible for critical element enrichment in carbonatites and to enhance our ability to identify and assess economic deposits. This project will work at various scales to meet this objective and will primarily focus on deposits within the US or our Critical Minerals Mapping Initiative collaborative Nations Canada and Australia.

The central objective of this project is to develop a greater understanding of deep bedrock groundwater circulation and its contribution to surface water metal loads in mineralized mountain blocks composed of sedimentary rocks. This work is being performed in cooperation with Lawrence Berkeley National Laboratory as part of a broader research program aimed at understanding processes controlling...

This Project integrates several geochemical tools—stable isotope geochemistry, noble gas geochemistry, active gas geochemistry, single fluid inclusion chemistry, and fluid inclusion solute chemistry—in studies of the processes that form mineral deposits and the processes that disrupt them during mining or natural weathering. Research is directed toward fundamental scientific questions or, in...

Understanding the genesis of ore deposits and their behavior in the environment is a subject of great importance to the Nation. A relatively new tool to aid in these efforts to investigate the origin and environmental effects of ore deposits is the use of "heavy" metal stable isotopes. Our research objectives are to utilize various isotopic systems to advance our understanding of ore genesis and...

Critical elements are essential to the modern economy and have potential supply chain disruptions, but compared to most base and precious metals, little work has been done in understanding ore-grade enrichments. Carbonatites are the primary source of the worlds light rare earth elements and niobium, and a potential source for heavy rare earths, scandium, tantalum, and thorium. Project objectives...

This project supports the USGS argon geochronology laboratory in Denver. The USGS 40Ar/39Ar geochronology laboratory is a state-of-the-art research facility for determining absolute ages of minerals and rocks. The 40Ar/39Ar laboratory contributes critical geochronology to individual USGS research projects and to partners in academia and other Federal agencies. This laboratory develops methodology...

The overall project objective is a comprehensive analysis of the natural and anthropogenic consequences of extensive ore and trace mineralization in the southern midcontinent of the U.S. with a focus on Missouri. This will be conducted at two scales: 1) landscape and 2) process-level. 1) Landscape scale using geospatial and machine learning techniques to combine multiple geochemical and geologic...

This project supports the Earth Mapping Resources Initiative (EarthMRI) by developing a mineral systems approach for defining focus areas. This project is investigating domestic sources of critical minerals in three sequential stages: inventory, research, and assessment. 1) Inventory the abundance of critical minerals in ore, minerals, and processed materials from major deposits in each system...