GEOCHEMICAL AND PETROGRAPHIC ANALYSES OF MICA MINE ADJACENT WETLANDS LOCATED IN THE BLUE RIDGE BELT, WESTERN NORTH CAROLINA

Small-scale Muscovite, or “mica” mining has been a large part of the culture of North Carolina starting as early as 400 years ago. The mica deposits studied here are included within the Blue Ridge Belt which contains a basement complex of older Precambrian mica gneiss and schist, hornblende gneiss and schist, migmatite, and granite gneiss, and locally extensive areas of younger Precambrian metasedimentary rocks.

The purpose of this study is to understand the relationship between the parent material of the bedrock and the local groundwater. The focus being on what processes within the bedrock support the carbon capture and retention in these areas past and present, and why the formation of wetlands adjacent to these mines occur. Which gives us a clearer picture on why the soils form as they have, and how these soils retain carbon material through time.

Thus far, a relatively high level of Carbon (29,659), Nitrogen (3094), and Sulfur (228) have been found within the sample. Next, a C/N ratio of 13.55% which is substantially higher than the average of 3.70% has been observed within soils adjacent to the Mica Mine, indicating high Carbon retention rates in proximity to the mine. However, water quality downstream of the mine has a higher pH, temperature, conductivity, and nitrate level in relation to the upstream headwaters likely as a result of contamination. Large-scale mica mining is known to introduce contaminants such as Aluminum, Iron, and Manganese to the groundwater, and despite the mines’ smaller size their proximity to the headwaters and groundwater will have an impact on the spring, affecting the downstream water quality. To continue this study, I will be completing mineral identification via Petrographic thin section analysis, as well as X-Ray fluorescence (XRF) bulk chemistry and X-Ray Diffraction (XRD) analysis. Further analysis of the bedrock material will determine if the Carbon retention and water quality are related to the Bedrock lithology.