Geological Survey of Canada, Current Research (Online) no. 2002-C5


Book Description

The purpose of this paper is to document results of electrical resistivity determinations of mineralized sericite schist specimens cut from a single sample collected from the Gold Lake area, Northwest Territories. Resistivity results are presented for frequencies of one hertz to one megahertz and for various orientations within the specimens. The results have application in interpreting ground electromagnetic surveys that are being conducted in the area.




Circum-Arctic Lithosphere Evolution


Book Description

The 5-year Circum-Arctic Lithosphere Evolution (CALE) program developed new constraints on the tectonic history of the central Amerasia basin of the Arctic Ocean. This volume is the final synthesis of the CALE program, which brought together an international team of scientists to develop integrated, multi-disciplinary understanding of the region. This approach, based on the integration of much new geological and geophysical data from onshore and offshore , is necessary to advance our understanding of this basin. Regional onshore-to-offshore transects are central to the 18 papers in this volume. The diverse science supporting these crust-to-mantle regional transects includes structural, geochronological, isotopic, potential fields, and seismic reflection and refraction data. Four chapters present circum-Arctic investigations by the regional CALE teams. The final chapter addresses pan-Arctic themes. This unique collaboration, relying on new data and new syntheses of existing data sheds new light on the history of the Arctic Ocean.













Critical Mineral Resources of the United States


Book Description

As the importance and dependence of specific mineral commodities increase, so does concern about their supply. The United States is currently 100 percent reliant on foreign sources for 20 mineral commodities and imports the majority of its supply of more than 50 mineral commodities. Mineral commodities that have important uses and face potential supply disruption are critical to American economic and national security. However, a mineral commodity's importance and the nature of its supply chain can change with time; a mineral commodity that may not have been considered critical 25 years ago may be critical today, and one considered critical today may not be so in the future. The U.S. Geological Survey has produced this volume to describe a select group of mineral commodities currently critical to our economy and security. For each mineral commodity covered, the authors provide a comprehensive look at (1) the commodity's use; (2) the geology and global distribution of the mineral deposit types that account for the present and possible future supply of the commodity; (3) the current status of production, reserves, and resources in the United States and globally; and (4) environmental considerations related to the commodity's production from different types of mineral deposits. The volume describes U.S. critical mineral resources in a global context, for no country can be self-sufficient for all its mineral commodity needs, and the United States will always rely on global mineral commodity supply chains. This volume provides the scientific understanding of critical mineral resources required for informed decisionmaking by those responsible for ensuring that the United States has a secure and sustainable supply of mineral commodities.







Mineral Commodity Summaries 2020


Book Description

Mineral Commodity Summaries 2019