The effectiveness of lithogeochemistry versus X-ray diffraction-defined mineralogy in outlining areas of volcanogenic massive sulfide-related alteration: A comparative study within the paleoproterozoic Baker Patton felsic Complex, Flin Flon, Manitoba, Ca

The volcanogenic massive sulfide deposit-hosting, Paleoproterozoic Baker Patton Complex, at Flin Flon, Manitoba, is the focus of a comparative study designed to evaluate the effectiveness of lithogeochemical data versus X-ray diffraction-derived, semi-quantitative mineralogical data, in detecting, defining, and vectoring within discordant volcanogenic massive sulfide alteration zones. The study was conducted at two scales, the local, or deposit scale, and the regional, or reconnaissance scale, in order to compare the usefulness of each method in delineating alteration at scales relevant to exploration. Discordant alteration in the Baker Patton Complex is defined by up to 2 km2 alteration zones of sencite and quartz alteration, and feldspar destruction, within slightly broader zones of chlorite alteration. The discordant alteration zones are best detected by anomalously low abundances of Na2O, CaO, and feldspar, and anomalously high abundances of K2O, MgO, quartz, muscovite, and chlorite. Semiconformable alteration in the western Baker Patton Complex, characterized by silicification of rhyolite lobes and flow margins, epidotization of hyaloclastite in lobe-hyaloclastite rhyolite facies, and a more pervasive spilitization, is best targeted by anomalously high abundances of SiO2, CaO, Na2O, K2O, and feldspar, and by the presence of epidote. With few exceptions, both analytical methods target the same alteration zones in the western Baker Patton Complex. In addition to its usefulness as a volcanogenic massive sulfide deposit-exploration tool, semi-quantitative phase analysis may be used in exploration to provide unique information, not obtainable from lithogeochemical data: (1) it can be used to determine the modal mineralogy of fine-grained, altered volcanic rocks, the most common host of volcanogenic massive sulfide deposits, (2) it can detect changes in mineralogy when there are no changes in bulk lithogeochemistry, and (3) it can be used to model hydrothermal systems, whereby alteration minerals and their abundances provide insight into the physicochemical conditions that existed within the hydrothermal system. At this time, lithogeochemical analysis is still the more practical exploration tool, being more routine, less costly, and less time-consuming than semi-quantitative X-ray diffraction analysis. Further studies are required to assess the effectiveness of semi-quantitative phase analysis as an exploration tool at other scales of exploration, and within various other geological environments.*; *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Microsoft Office; Adobe Acrobat.