Heather L. Parks Michael L. Zientek Dean M. Peterson Nicole Hoffmann Phillip Larson Jeffrey L. Mauk 20250417 tabular digital data https://doi.org/10.5066/P13UFQYF This dataset includes geochemical analytical results of rock samples sourced from drill core and hand specimens from the South Kawishiwi, Bald Eagle, Crocodile Lake, Cucumber Lake intrusions, and the Logan Sills, in the Duluth Complex, Minnesota. The dataset includes whole-rock and elemental geochemistry information with analysis methods used and qualifier (filtered) information where applicable, along with CIPW (Cross, Iddings, Pirsson, and Washington) norm data. The data represents a 'best value' version of the data, where the analytical results sourced from the superior analytical method for a particular element were used. The best values methods were picked based upon the method with the lowest detection limit. When two methods had the same lower detection limit, the highest value analytical result was retained as the best value. If a sample was analyzed multiple times, the additional analysis values can be found in the columns ending in "..._all". This data release includes the following files: 1) .csv file (MCR_USGS_geochem_BV.csv) that includes analytical geochemical data and attribute information. 2) .csv file (MCR_USGS_geochem_data_dictionary.csv) of a data dictionary which includes the .csv file column heading and shapefile field definitions. 3) .csv file (MCR_USGS_geochem_methods.csv) of all methods used in the analysis and their descriptions. 4) .csv file (MCR_USGS_geochem_references.csv) that lists sources used in the Strat_03, Strat_04, and Strat_05 columns in the "MCR_USGS_geochem_BV.csv" file. 5) shapefile (MCR_USGS_geochem_locations.shp) representing the locations of samples and drill hole collars. The purpose of this dataset is to compile and integrate geochemical data from the Duluth Complex, Minnesota to facilitate geologic mapping, petrologic studies, mineral resource assessments, definition of geochemical baseline values and statistics, element concentrations and associations, environmental impact assessments, and studies in public health associated with geology. 20150601 20180601 ground condition Complete None planned -91.9913 -90.0464 48.0774 47.5749 ISO 19115 Topic Category geoscientificInformation USGS Thesaurus geochemistry critical minerals USGS Metadata Identifier USGS:675b332fd34e08c81ed96c4c Common geographic areas Minnesota None. Please see 'Distribution Info' for details. These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Heather L Parks USGS - SOUTHWEST REGION Geologist mailing and physical

904 W Riverside

Room 202

Spokane WA 99201 509-368-3114 hparks@usgs.gov Duluth Metals Limited Microsoft Windows 11; Esri ArcGIS Pro version 3.2 Quality assurance and quality control procedures for analysis were utilized by the geochemistry laboratories. Sample attribute information was checked for accuracy. Unique combinations of related attributes were reviewed to ensure consistency in spelling and coding. Hierarchical consistency in rock type and rock unit designations were checked. All data values fall within expected ranges. Data was checked for omission and duplication. Geospatial locations fall where expected. This data is constricted to the Duluth Complex, Minnesota. Horizontal locations are accurate to approximately 50 feet. Drill core locations are representative of the drill hole collar and are not intended to represent down-hole x-y locations for inclined holes. Vertical locations are accurate to approximately 1 foot. A. Johannsen 19310601 publication https://www.nature.com/articles/129636a0 Digital and/or Hardcopy 19310601 ground condition Johannsen (1931) The CIPW norm calculations were based upon this report. Drill core and field samples were collected and sent in for geochemical analysis. Analytical results were compiled into spreadsheet format. Sample information, such as information about the rock type, stratigraphy, sample location, sample source, etc. were added. A 'best values' version of the data was created representing analytical results sourced from the superior analytical method for a particular element, where a single sample was analyzed multiple times. The best values methods were picked based upon the method with the highest precision, or lowest detection limit. When two methods had the same lower detection limit, the highest value analytical result was retained as the best value. Samples were analyzed by different labs, at different times, and therefore have differing amounts of significant figures reported. Geologic names were cross-checked against the USGS National Geologic Map Database Geolex Search (https://ngmdb.usgs.gov/Geolex/search). Names that were not found using the Geolex search are lower case in this dataset, indicating informal names. CIPW volume norm data was calculated using the "CIPW Norm Hollacher.xls" spreadsheet (https://www.whitman.edu/geology/winter/Petrology/CIPW%20Norm%20Hollacher.xls) created by Kurt Hollocher, of Union College, based upon the CIPW norm calculations from Johannsen (1931). Below detection limit values were changed to 1/2 value for the CIPW norm calculation. A calculated value was used for Fe2O3 and FeO as input into the CIPW norm spreadsheet for samples that did not have Fe2O3 or FeO data. The following formula was used to calculate the missing Fe2O3 values for samples that have both Fe2O3_total and FeO data: Fe2O3=Fe2O3_total-(FeO*1.1113). The following formula was used to calculate the missing Fe2O3 values for samples that have only FeO data: Fe2O3=Fe2O3_total-(Fe2O3_total*0.6). The following formula was used to calculate the missing FeO values for samples that have only Fe2O3_total data: FeO=Fe2O3_total*0.8998. Sample locations and drill hole collar locations were used to create a shapefile representing the locations of the drill hole collars and samples. Note that the locations for samples sourced from drill holes represent the surface location of the drill hole collar, and not the downdip location. See the 'MCR_USGS_geochem_references.csv' file for a list of references used in the 'MCR_USGS_geochem_BV.csv' file. Johannsen (1931) 20241215 Vector Entity point 121 Universal Transverse Mercator 15 0.9996 -93.0 0.0 500000.0 0.0 coordinate pair 0.6096 0.6096 meters North_American_Datum_1983 GRS 1980 6378137.0 298.257222101 MCR_USGS_geochem_locations.shp Shapefile representing drill hole collar and sample locations. Producer Defined FID Internal feature number. ESRI Sequential unique whole numbers that are automatically generated. Shape Feature geometry. ESRI Shape type. SampleSrc The source of the sample. Producer Defined natural exposure/outcrop Sample was collected from a surface location. Producer defined drill core Sample was collected from drill core. Producer defined Field_ID Name of the sample as entered on the geochemistry sample submission form. The "[multiple]" notation is used for the samples that were sourced from drill core, as there are many field IDs that correlate to each single drill hole location. Producer Defined Name of the sample as entered on the geochemistry sample submission form. Drill_hole Drill hole identifier. NA=not applicable. Producer Defined NA not applicable Producer defined Drill hole identifier. Lat_NAD83 Latitude, in decimal degrees, in NAD 1983 datum. Producer Defined 47.60783231 48.051109 decimal degrees Lon_NAD83 Longitude, in decimal degrees, in NAD 1983 datum. Producer Defined -91.99127737 -90.048893 decimal degrees A data dictionary (MCR_USGS_geochem_data_dictionary.csv) is included with this report that lists the column headings in the MCR_USGS_geochem_BV.csv, MCR_USGS_geochem_methods.csv, and MCR_USGS_geochem_references.csv files and provides a description for the column contents. Producer defined. GS ScienceBase U.S. Geological Survey mailing address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P13UFQYF None 20250501 Heather L Parks U.S. Geological Survey, SOUTHWEST REGION Geologist mailing address

W 904 Riverside

Spokane WA 99201 US 509-368-3114 509-368-3199 hparks@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998