Critical commodity studies, Stillwater Complex, Montana and Duluth Complex, Minnesota
Completed
By Geology, Minerals, Energy, and Geophysics Science Center
June 18, 2018
Scientific research can make our resource assessments of critical minerals more effective. This project focuses on the Stillwater Complex, Montana, which has rocks enriched in platinum-group elements (PGE), chromium, cobalt, and nickel. Project objectives are to update databases, evaluate new mapping techniques, document new styles of mineralization, and document and support research on the Stillwater Complex PGE deposit, the J-M Reef.
Science Issue and Relevance
The platinum-group elements (PGE) are consistently identified as critical minerals for many nations, including the United States, with the only primary bedrock PGE deposit in the U.S. being the J-M Reef in the Stillwater Complex, Montana. Scientific research can make our resource assessments of critical minerals more effective. For example, we can study representative deposit types in order to understand what we should be looking for and how we should look for them. Using this information, we can build the scientific databases we need to conduct geologically based assessments and identify gaps in our knowledge. Occasionally, new, provocative research suggests our paradigms may be incorrect and calls for us to go into the field to test ideas. Although the J-M Reef has been mined since 1986, very little quantitative rock geochemistry has been published.
Methodology to Address Issue
The last resource assessment of the Stillwater Complex (Zientek, 1993) was conducted over 20 years ago, just after the Stillwater PGE mine went into production. Our project will conduct the following tasks to make resource assessments of critical minerals more effective:
- Update map database from the last resource assessment (over 20 years ago) for the Stillwater Complex,
- Test and apply new mapping and analysis techniques for mafic and ultramafic layered intrusions,
- Conduct a comparative study between contact-type deposits in Stillwater and those at Duluth (Midcontinent region), and
- Summarize and publish the USGS data on the J-M Reef.
Below are data or web applications associated with this project.
Filter Total Items: 18
Stillwater Complex, Montana: Logs of core drilled by Chrome Corporation of America in the Mountain View area, 1988 to 1990
This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and 17 individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from the Mou
Structural measurements and their calculated surface traces, South Kawishiwi area, Duluth Complex, Minnesota
This dataset includes a point shapefile representing structural measurements taken from a study area near the South Kawishiwi Intrusion in the Duluth Complex, Minnesota and a line shapefile representing the surface traces of the structural measurements. The structural measurements point file consists of a compilation of data from multiple published and unpublished sources. The surface trace file w
Geochemistry of rocks and rock fabric data near the hanging wall contact to the Reef Package, Stillwater Complex, Montana, USA
The Reef Package is a sequence of coarse-grained cumulates that host the J-M Reef Pd-Pt deposit in the Stillwater Complex of Montana. The top of the Reef Package marks the top of economic-grade platinum-group element mineralization and is identified by a distinct change in rock fabric, from the coarse-grained rocks of the Reef Package to finer-grained cumulates in the hanging wall. This dataset ta
Thin section images of drill core and hand samples from the South Kawishiwi Intrusion, Duluth Complex, Minnesota
This dataset includes photographic images of thin sections created from hand samples and drill core sourced from the South Kawishiwi Intrusion, Duluth Complex, Minnesota, along with two shapefiles representing the locations of the samples and drill hole collars. The samples were collected and core was drilled in order to define copper-nickel-platinum-group element resources associated with the Sou
Thin section images of drill core and hand samples from the Stillwater Mine area, Stillwater Complex, Montana
This dataset includes photographic images of thin sections created from hand samples and drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the underground samples and drill hole collars. The samples were collected and core was drilled in order to define platinum-group element resources associated with the J-M Reef at the Stillwater Mine in the St
Thin section images of xenoliths from north of the Stillwater Complex, Montana
This dataset includes photographic images of thin sections made from xenolith samples collected from the Sliderock Mountain and Susie Peak plutons, Montana, along with a shapefile representing the locations of the samples. The plutons are located north of the Stillwater Complex, Montana, which is exposed along the northern side of the Beartooth Mountains in Montana. To the north of the Stillwater
Stillwater Complex, Montana: Logs of core drilled by Anaconda in the Nye Basin area, 1968 to 1982
This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and fourteen individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from t
Thin section images of drill core from the Chrome Lake area in the Stillwater Complex, Montana
This dataset includes photographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the drill holes. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a
Thin section images of AMAX drill core from the Stillwater Complex, Montana
This dataset includes photographic and micrographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the drill holes. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. See data release https://doi.org/10.5066/p9w5kp8u for accompanying drill log data.
Stillwater Complex, Montana: Logs of core drilled by Cyprus in the Chrome Lake area, 1971 to 1980
This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and fourteen individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from t
Thin section images of drill core from the Crescent Creek area in the Stillwater Complex, Montana
This dataset includes photographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the location of the drill hole. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a h
Stillwater Complex, Montana: Logs of core drilled by Anaconda in the Benbow area, 1969 to 1973
This dataset includes pdf representations of drill core logs showing associated drill core information, a pdf of the explanation for the lithology and structure sections of the logs, a shapefile of the locations of the drill holes, and eleven individual .csv files of tabular data that was compiled from hand written drill core logs. The drill core is from the Stillwater Complex, Montana and was dri
Below are publications associated with this project.
Origin of the J-M Reef and Lower Banded series, Stillwater Complex, Montana, USA
The origin and parental magma for layered cumulates in the Lower Banded series (LBS) and the J-M Reef Pd-Pt deposit of the Stillwater Complex remains poorly constrained. We present whole-rock lithogeochemistry and mineral chemistry from LBS rocks collected from drill holes and surface samples from the Mountain View area of the complex that in total span nearly the entirety of the LBS stratigraphy.
Authors
Michael Jenkins, James E. Mungall, Michael L. Zientek, Gelu Costin, Zhuo-sen Yao
The nature and composition of the J-M Reef, Stillwater Complex, Montana, USA
In this contribution, we analyze 30 years of mine development data and quantitatively identify the processes that control the grade and tenor of the mineralized rock. An assay database of more than 60,000 samples was used to examine variations in ore grade and tenor of the sulfide mineralization in the J-M reef horizon of the Stillwater Complex along the strike and down the dip of the deposit in t
Authors
Michael Jenkins, James E. Mungall, Michael L. Zientek, Paul Holick, Kevin Butak
Mapping the 3-D extent of the Stillwater Complex, Montana—Implications for potential platinum group element exploration and development
Geophysical models characterize the exposed and interpreted buried extent of the Stillwater Complex, critical for understanding the origin of the layered mafic intrusion and its associated high-grade platinum group element resources. The 3D models, constrained by gravity, magnetic, xenolith, seismic, borehole, and rock property data indicate that the likely maximum extent of the Stillwater Complex
Authors
Carol A. Finn, Michael L. Zientek, Heather L. Parks, Dana E. Peterson
The surface trace tool — Modeling complex planar interactions using ArcGIS
The surface trace tool comprises a Python script written for ArcGIS that will determine the line of intersection between a planar feature and a surface. Specifically, this tool was designed for geologic applications where geologic planar-feature orientations are reported as strike and dip, and the intersecting surface is the ground. The tool output will show how planar geologic layers intersect wi
Authors
Drew B. Adams, Heather L. Parks
Scientific research can make our resource assessments of critical minerals more effective. This project focuses on the Stillwater Complex, Montana, which has rocks enriched in platinum-group elements (PGE), chromium, cobalt, and nickel. Project objectives are to update databases, evaluate new mapping techniques, document new styles of mineralization, and document and support research on the Stillwater Complex PGE deposit, the J-M Reef.
Science Issue and Relevance
The platinum-group elements (PGE) are consistently identified as critical minerals for many nations, including the United States, with the only primary bedrock PGE deposit in the U.S. being the J-M Reef in the Stillwater Complex, Montana. Scientific research can make our resource assessments of critical minerals more effective. For example, we can study representative deposit types in order to understand what we should be looking for and how we should look for them. Using this information, we can build the scientific databases we need to conduct geologically based assessments and identify gaps in our knowledge. Occasionally, new, provocative research suggests our paradigms may be incorrect and calls for us to go into the field to test ideas. Although the J-M Reef has been mined since 1986, very little quantitative rock geochemistry has been published.
Methodology to Address Issue
The last resource assessment of the Stillwater Complex (Zientek, 1993) was conducted over 20 years ago, just after the Stillwater PGE mine went into production. Our project will conduct the following tasks to make resource assessments of critical minerals more effective:
- Update map database from the last resource assessment (over 20 years ago) for the Stillwater Complex,
- Test and apply new mapping and analysis techniques for mafic and ultramafic layered intrusions,
- Conduct a comparative study between contact-type deposits in Stillwater and those at Duluth (Midcontinent region), and
- Summarize and publish the USGS data on the J-M Reef.
Below are data or web applications associated with this project.
Filter Total Items: 18
Stillwater Complex, Montana: Logs of core drilled by Chrome Corporation of America in the Mountain View area, 1988 to 1990
This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and 17 individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from the Mou
Structural measurements and their calculated surface traces, South Kawishiwi area, Duluth Complex, Minnesota
This dataset includes a point shapefile representing structural measurements taken from a study area near the South Kawishiwi Intrusion in the Duluth Complex, Minnesota and a line shapefile representing the surface traces of the structural measurements. The structural measurements point file consists of a compilation of data from multiple published and unpublished sources. The surface trace file w
Geochemistry of rocks and rock fabric data near the hanging wall contact to the Reef Package, Stillwater Complex, Montana, USA
The Reef Package is a sequence of coarse-grained cumulates that host the J-M Reef Pd-Pt deposit in the Stillwater Complex of Montana. The top of the Reef Package marks the top of economic-grade platinum-group element mineralization and is identified by a distinct change in rock fabric, from the coarse-grained rocks of the Reef Package to finer-grained cumulates in the hanging wall. This dataset ta
Thin section images of drill core and hand samples from the South Kawishiwi Intrusion, Duluth Complex, Minnesota
This dataset includes photographic images of thin sections created from hand samples and drill core sourced from the South Kawishiwi Intrusion, Duluth Complex, Minnesota, along with two shapefiles representing the locations of the samples and drill hole collars. The samples were collected and core was drilled in order to define copper-nickel-platinum-group element resources associated with the Sou
Thin section images of drill core and hand samples from the Stillwater Mine area, Stillwater Complex, Montana
This dataset includes photographic images of thin sections created from hand samples and drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the underground samples and drill hole collars. The samples were collected and core was drilled in order to define platinum-group element resources associated with the J-M Reef at the Stillwater Mine in the St
Thin section images of xenoliths from north of the Stillwater Complex, Montana
This dataset includes photographic images of thin sections made from xenolith samples collected from the Sliderock Mountain and Susie Peak plutons, Montana, along with a shapefile representing the locations of the samples. The plutons are located north of the Stillwater Complex, Montana, which is exposed along the northern side of the Beartooth Mountains in Montana. To the north of the Stillwater
Stillwater Complex, Montana: Logs of core drilled by Anaconda in the Nye Basin area, 1968 to 1982
This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and fourteen individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from t
Thin section images of drill core from the Chrome Lake area in the Stillwater Complex, Montana
This dataset includes photographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the drill holes. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a
Thin section images of AMAX drill core from the Stillwater Complex, Montana
This dataset includes photographic and micrographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the drill holes. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. See data release https://doi.org/10.5066/p9w5kp8u for accompanying drill log data.
Stillwater Complex, Montana: Logs of core drilled by Cyprus in the Chrome Lake area, 1971 to 1980
This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and fourteen individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from t
Thin section images of drill core from the Crescent Creek area in the Stillwater Complex, Montana
This dataset includes photographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the location of the drill hole. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a h
Stillwater Complex, Montana: Logs of core drilled by Anaconda in the Benbow area, 1969 to 1973
This dataset includes pdf representations of drill core logs showing associated drill core information, a pdf of the explanation for the lithology and structure sections of the logs, a shapefile of the locations of the drill holes, and eleven individual .csv files of tabular data that was compiled from hand written drill core logs. The drill core is from the Stillwater Complex, Montana and was dri
Below are publications associated with this project.
Origin of the J-M Reef and Lower Banded series, Stillwater Complex, Montana, USA
The origin and parental magma for layered cumulates in the Lower Banded series (LBS) and the J-M Reef Pd-Pt deposit of the Stillwater Complex remains poorly constrained. We present whole-rock lithogeochemistry and mineral chemistry from LBS rocks collected from drill holes and surface samples from the Mountain View area of the complex that in total span nearly the entirety of the LBS stratigraphy.
Authors
Michael Jenkins, James E. Mungall, Michael L. Zientek, Gelu Costin, Zhuo-sen Yao
The nature and composition of the J-M Reef, Stillwater Complex, Montana, USA
In this contribution, we analyze 30 years of mine development data and quantitatively identify the processes that control the grade and tenor of the mineralized rock. An assay database of more than 60,000 samples was used to examine variations in ore grade and tenor of the sulfide mineralization in the J-M reef horizon of the Stillwater Complex along the strike and down the dip of the deposit in t
Authors
Michael Jenkins, James E. Mungall, Michael L. Zientek, Paul Holick, Kevin Butak
Mapping the 3-D extent of the Stillwater Complex, Montana—Implications for potential platinum group element exploration and development
Geophysical models characterize the exposed and interpreted buried extent of the Stillwater Complex, critical for understanding the origin of the layered mafic intrusion and its associated high-grade platinum group element resources. The 3D models, constrained by gravity, magnetic, xenolith, seismic, borehole, and rock property data indicate that the likely maximum extent of the Stillwater Complex
Authors
Carol A. Finn, Michael L. Zientek, Heather L. Parks, Dana E. Peterson
The surface trace tool — Modeling complex planar interactions using ArcGIS
The surface trace tool comprises a Python script written for ArcGIS that will determine the line of intersection between a planar feature and a surface. Specifically, this tool was designed for geologic applications where geologic planar-feature orientations are reported as strike and dip, and the intersecting surface is the ground. The tool output will show how planar geologic layers intersect wi
Authors
Drew B. Adams, Heather L. Parks