HEAVY METAL XRF ANALYSIS OF ULTRAMAFIC-DERIVED SERPENTINE SOILS LOCATED ON SERPENTINE BARRENS IN PENNSYLVANIA

Serpentine soils have been the subject of much study, due to both their sparse yet wide-ranging occurrence, and their unique mineral and chemical properties. The formational processes and parent material of the soil can be correlated with these distinctive chemical properties. Serpentine soils are derived from ultramafic rocks--both igneous and metamorphic, such as peridotite and serpentinite--and because these rocks originate in the mantle, their chemical makeup is naturally different than most rocks formed in the crust. Additionally, the weathering characteristics of the serpentine soils, including their tendency to maintain compositions very similar to the parent rock, lead the soil to exhibit attributes unlike surrounding soils. One of these attributes is the large quantity of heavy metals that remain in the soils--such as chromium and nickel. These metals, along with high quantities of magnesium and low quantities of calcium, cause the areas where these soils occur, known as “serpentine barrens”, to display a unique and limited flora and fauna. This paper will serve as a geochemical analysis of heavy metal content in serpentine barrens in Pennsylvania. By using X-ray fluorescence, it will be possible to examine the chemical content of these soils and map any similarities and differences between them. This will help in the understanding of soils in this region, as well as function as a comparative analysis with geochemical analysis of serpentine soils in other localities.