Finish Logging of Duluth Complex Drill Core

Abstract

From 1988 through 2005, NRRI personnel had logged 955 drill holes from the basal zone of the Duluth Complex. The major result of all this effort was the establishment of igneous stratigraphic packages, which in turn, were used to improve our understanding of the mineralization controls on the Cu-Ni deposits and the distribution of Platinum Group Elements (PGE). However, at the beginning of the biennium there were still over 220 drill holes (226,000 feet of core) that remained to be re-logged from portions of the Partridge River and South Kawishiwi intrusions. The main objective of this proposal was to complete a logging campaign of these remaining holes and establish a complete stratigraphic section for these two intrusions of the Duluth Complex. To date, 224 holes have been relogged for this project totaling 198,979 feet of drill core. This total includes several holes that were recently drilled in the Maturi Extension/Nokomis deposit by Duluth Metals, and several recently found drill cores from the Dunka Pit deposit. All of the newly logged holes, see appendix, are located in eight deposits within the Partridge River and South Kawishiwi intrusions; including a few scattered holes in the Cloquet Lake and Tuscarora intrusions. The vast majority of relogged holes were from the Babbitt/Mesaba deposit due to the incredibly large number of drill holes drilled there in the first place. While this project made a significant dent in the total amount of holes logged at the Babbitt deposit, there are still about 20 holes that yet remain to be logged. In an addendum to this report, these drill holes at the Babbitt deposit will be logged, and an unknown number of additional drill holes at the Maturi Extension will be logged.