Browsing by Subject "Biwabik Iron Formation"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Compile and Make Digital the Lithologies for all NRRI Drill Logs, with Emphasis on the Duluth Complex Drill Holes (An Addendum to an Earlier NRRI Database)
    (University of Minnesota Duluth, 2009) Severson, Mark J; Oreskovich, Julie A; Patelke, Marsha Meinders
    This report and associated databases are updates on many of the holes that have been recently logged by the Natural Resources Research Institute (NRRI) in the Keweenawan Duluth Complex, the Paleoproterozoic Biwabik Iron Formation of the Mesabi Iron Range, and the Archean Deer Lake Complex of northeastern Itasca County, Minnesota. The main emphasis of this project was to update some of the databases that were presented in an earlier NRRI report (Patelke, 2003) with regard to lithologies in Duluth Complex drill holes that were logged by the NRRI since 2003 (and discussed in Severson and Hauck, 2008). To date, all of the publically available drill holes (except for around 30 drill holes) have now been logged in the Duluth Complex by the NRRI. These 30 holes are all that are missing from either the databases in this report or the databases in Patelke (2003). It is strongly suggested that the databases herein be combined, at the user’s discretion, with corresponding databases in Patelke (2003) in order to make an all- encompassing database for lithologies for all NRRI logged drill holes in the Duluth Complex. A secondary goal of this project was to present a header file database for all the holes that were recently drilled in the Duluth Complex (post-2003). Most of these holes are not yet publically available, but data regarding drill hole locations can be gleaned from abandonment files. Combining Duluth Complex header files in this report with the similar header file in Patelke (2003) could provide an all-encompassing database of locations for all of the holes drilled to date in the Duluth Complex (pre-2010 data). This combining of the data is left to the user’s discretion. Lastly, additional goals of this project (time permitting) were to present lithologic databases for all holes logged by the NRRI in the Mesabi Iron Range and, to a much lesser extent, holes logged by the NRRI in the Deer Lake Complex. The database for the Mesabi Iron Range contains information for almost 300 drill holes (over 5,947 lines of lithologic data) in regard to the lithologic picks pertaining to informal members and submembers of the iron-formation. The data in this file is about 80% complete in that not all of the iron-formation submembers are presented for holes drilled at the Keetac Taconite mine or in the Coleraine, MN, area (the latter holes are discussed in Zanko et al., 2003).
  • Thumbnail Image
    Item
    Geologic and Stratigraphic Controls of the Biwabik Iron Formation and the Aggregate Potential of the Mesabi Iron Range, Minnesota
    (University of Minnesota Duluth, 2009) Severson, Mark J; Heine, John J; Patelke, Marsha Meinders
    The taconite mines on the Mesabi Iron Range of northeastern Minnesota generate millions of tons of mined waste rock annually that could potentially be used as aggregate material in road building projects. Paramount to defining potential aggregate horizons within the mined ironformation is an understanding of the stratigraphy as it relates to mined ore units and waste units at each of the respective taconite mines. However, each mine uses a different submember terminology to designate the various ore and waste horizons. The major emphasis of this investigation was to produce a stratigraphic “Rosetta Stone” of the Biwabik Iron Formation that ties the stratigraphy and differing submember terminology of one mine to all of the other mines on the Mesabi Iron Range. Toward that end, the Natural Resources Research Institute (NRRI) looked at core from over 380 drill holes, and some mine exposures, in the central and western Mesabi Iron Range (Biwabik to Coleraine, MN area) to develop a stratigraphic system that links all of the mined ore and waste submembers. The methodology used in this investigation was to log multitudinous deep drill holes from a single mine, hang all of the drill holes on a common datum (bottom of the Lower Slaty member), and then correlate all of the submembers, as used by that particular mine, making note of bedding features and other unique features that define a particular submember. This same system of “logging, hanging, and correlating” was done at each of the taconite mines (seven different mines/areas along the Mesabi Iron Range) to better understand each mine’s submember terminology. The hung stratigraphic-sections from each mine were then used to collectively make generalized stratigraphic columns for each of the mines. These stratigraphic columns were then added to the “Rosetta Stone” (Plate II of this report) that is used to illustrate how the submembers at one mine correlate with similar submembers at all of the other mines. In the end, this investigation identified 25 major “Rosetta” units that define the stratigraphy of the Biwabik Iron Formation that can be used to link together all of the differing submember nomenclatures from the various taconite mines. This division of the iron-formation into 25 major units, based primarily on their overall bedding characteristics, is applicable to only the central and western Mesabi Iron Range and does not include the more highly metamorphosed iron-formation of the eastern Mesabi Iron Range, e.g., to the east of Aurora, MN.
  • Thumbnail Image
    Item
  • Thumbnail Image
    Item
  • Thumbnail Image
    Item
    Western Mesabi Iron Resources of the Future
    (University of Minnesota Duluth, 2022-09-15) Johnson, Rodney C; Mlinar, Matthew A; Spigarelli, Brett P; Post, Sara P
    The purpose of this study was to initiate a long-term comprehensive characterization program of the remaining iron resources of the Mesabi Iron Range to provide a foundation for the future iron industry in Minnesota. This data is being used to direct research in the areas of reducing reliance on fossil fuels, reducing emissions, and to identify and develop value-added iron products that could be produced from underutilized portions of Minnesota iron resources. Two complete sections of the iron formation were analyzed in this study. The results have contributed to a better understanding of the mineralogical variability within the iron formation; the impacts of oxidation on iron product quality; the potential for new iron-based products; and the presence of trace elements.