USGS - science for a changing world

USGS Science in Alaska

white dotscience portal: white dotalaska science center:
All USGS This site only

Large Mafic Igneous Province (LIP) in central Alaska

This project is a collaborative with the BLM Delta River Mining District (DRMD) study to be completed in FY05. USGS is investigating the structural controls on the northern- and western-most segment of a continental-scale mafic large igneous province (LIP) - the Triassic Nikolai Greenstone).

Principal Investigators:
Schmidt, Jeanine M.

Project Contacts:

Collaborators:
BLM - Alaska State Office


Status: completed
Start Year: 2003
End Year: 2005

Location:
Clearwater Mountains
Fish Lake
Tangle Lakes

USGS Mission Area and Program:
Energy and MineralsMineral Resources

Web Links:
3D model of an ultramafic feeder system to the Nikolai Greenstone mafic large igneous province
Magnetotelluric data in the Delta River mining district, near the Tangle Lakes area of SC Alaska
Principal Facts for 463 gravity stations in the vicinity of Tangle Lakes, EC Alaska
Magnetotelluric data along the Tangle Lakes profile, Alaska
2D inverse and 3D forward modeling of MT data to evaluate mineral potential, Amphitheatre Mtns.
A kinematic model for the southern AK orocline based on regional fault patterns
Geophysical data revearl the crustal structure of the AK Range orogen
Geophysical investigation of the Denali Fault and AK Range orogen
Metallogeny of the Nikolai large igneous province in southern AK
Gravity and magnetic character of SC AK: constraints on geologic interpretation
Crustal structure of the AK Range orogen and Denali fault along the Richardson Highway

Keywords:
Solid Earth > Rocks/Minerals > Bedrock Lithology
Solid Earth > Geomagnetism > Electrical Field
Solid Earth > Tectonics > Faults
Solid Earth > Geodetics/Gravity > Gravity
Solid Earth > Rocks/Minerals > Igneous Rocks
Solid Earth > Geomagnetism > Magnetic Anomalies
Solid Earth > Geochemistry > Major Elements
Solid Earth > Natural Resources > Metals
Solid Earth > Tectonics > Stratigraphic Sequence
Solid Earth > Geochemistry > Trace Elements

Abstract


This project is a collaborative with the BLM Delta River Mining District (DRMD) study to be completed in FY05. USGS is investigating the structural controls on the northern- and western-most segment of a continental-scale mafic large igneous province (LIP) - the Triassic Nikolai Greenstone). New microfossil and radiometric samples may provide age control for the LIP intrusions and their host rocks. Modeling of new ground and airborne poential field and magnetotelluric geophysical data in a stratigraphic context provides a regional framework for the location of the intrusions and detailed profiles of the structural context of several of the largest exposed bodies. Intrusive rocks that are part of the Nikolai LIP system have very high potential for nickel-copper and platinum-group element deposits. These intrusions are abundant, extensive, and chemically differentiated in the central Alaska Range, unlike many other segments of the Nikolai LIP. This area is the focus of ongoing mineral exploration and accelerated land transfers between the BLM and the State of Alaska. The USGS study identifies the structures that control the primary Triassic emplacement of magmas. This project provided framework geology to more accurate assessment of the character, and possible locations of mineral concentrations.

Project metadata record

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://alaska.usgs.gov/portal/project.php?project_id=55
Page Contact Information: ascweb@usgs.gov
Page Last Modified: August 07 2014 13:53:11.