Petrology and Cu-Ni-PGE Mineralization of the Bovine Igneous ...

asic rock types noted above and contains several horizons of disseminated and net-textured
sulfide minerals. He notes that metal grades are low through most of the intrusion, typically
less than .5 % Cu and Ni, and less than 350 ppb Pt and Pd (Fig. 6). One interval in the Little
BIC intrusion and extending into the country rock has been found which contains significantly
higher metal tenors comparable to the Eagle intrusion and the other mineralized ultramafic
intrusions of the MCR (Rossell, 2008).
Two other studies on the intrusion are currently in progress, but have not yet been fully
published. A sulfur isotope study of the BIC by an undergraduate student under the direction
of Dr. Ed Ripley at Indiana University is to be released in the summer of 2011. Initial findings
of said study published in a 2010 GSA abstract indicated a δ 34 S range of -.41 to 1.23‰. This
sulfur isotope range is consistent with sulfur derived directly from the mantle. However the
quantity of sulfur present in the BIC suggests that some additional sulfur must have been
added. Schulz and Nicholson (2009) presented the whole rock data recently collected from
about eight samples from the BIC and compared the data to other early mafic-ultramafic MCR
intrusions and to diabase dikes in the Baraga Basin to see if there is a possible genetic link.
Schulz and Nicholson found that the trace element geochemistry of the BIC was very similar to
those of high titanium alkali basalt dikes found nearby in the Baraga basin suggesting a
possible petrogenetic link. The USGS scientists also collected a sample for U-Pb dating of
zircon or baddelyite but were unsuccessful in acquiring datable material.
1.3 Objectives
The main goals of this study are to evaluate the emplacement, crystallization, and
mineralization history of the BIC. The principle objectives that will be pursued to accomplish
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