Geochemistry and geochemical modeling of unsaturated zone in a tropical region in Urânia, São Paulo state, Brazil

CO2 and O2 dynamics in human-impacted watersheds in the state of São Paulo, Brazil

“…For instance, most soils in the Piracicaba River basin had a pH lower than 5 (Krusche et al 2002). However, soil-solution pH sampled in the western portion of the state of São Paulo had values around 7 (Bertolo et al 2006). Assuming that this soil-solution pH also occurs in the other basins, 80% of the DIC will be composed of HCO 3 -and 20% by aqueous CO 2.…”

“…In our basins, one of the most important reactions was the formation of kaolinite from Alsilicates and dissolution of calcite and dolomite (Meng and Maynard 2001;Sracek and Hirato 2002;Conceição and Bonotto 2004). Other studies emphasize that Ca 2+ and Mg 2+ are the main cations produced by rock weathering in the region (Bertolo et al 2006;Bonoto 2006). Accordingly, if groundwater is an important supplier of HCO 3 -in a plot of HCO 3 -versus Ca 2+ + Mg 2+ , the river samples should plot in a line 2:1.…”

Coupled reactive flow and transport modeling of CO2 sequestration in the Mt. Simon sandstone formation, Midwest U.S.A.

“…Geometric surface areas are computed from an assumed grain shape and size distribution. The ratio of BET/geometric surface is known as the "surface roughness" (Bertolo et al, 2006), but also includes internal porosity. The SR of naturally weathered feldspars varies from ∼250 to 3000 (Blum, 1994;White et al, 1996;White and Peterson, 1990), with the SR increasing systematically with the qualitative degree of corrosion and internal porosity developed (White et al, 1996).…”

Anomalous content of chromium in a Cretaceous sandstone aquifer of the Bauru Basin, state of São Paulo, Brazil

“…Thirteen undisturbed soil samples were taken from a borehole at depths ranging from 0.4 m to 11.5 m. This borehole ("PC" well) was used for installation of a vadose zone monitoring station (Bertolo et al, 2006). In addition, 40 core samples were collected at selected depths of between 14 m and 100 m from two deep boreholes, where two nested multi-level monitoring wells ("PM" wells) were subsequently installed.…”