Poster 59: This thesis focuses on soil formation by chemical weathering of uplifted coastal terraces in a high precipitation region. Soil maturity is often reflected in the soil’s smectite-kaolinite ratio. Younger soils are generally more smectite-rich and older soils, which have experienced more weathering and more leaching, are generally more kaolinite-rich. However, other factors, rainfall especially, also affect the maturation process. This can cause different rates of maturation within different soils that are dated to be the same age. In this thesis I seek to test three main hypotheses: 1) that tropical soils in a rainy environment evolve rapidly from Holocene smectite-dominated to Pleistocene kaolinite-dominated; 2) that the mineralogy and geochemical fingerprint of the Osa terrace soils can be used to identify and correlate distinct terraces; and 3) that point 2 will reveal spatial relationships that exhibit consistent terrace characteristics (i.e. uplift from sea level, soil mineralogy, soil geochemistry, age, and elevation).
