Salt crystallization can severely damage anisotropic foliated rocks, therefore it is necessary to have an understanding of crystallization process. The present study was conducted to investigate the effect of salt crystallization on Arakʾs calcareous slates, as anisotropic rocks of Mesozoic. To compare salt crystallization weathering (EN 12370 norm was used up to 30 cycles) with natural weather...

Estimation of the temperature dependence of natural feldspar weathering in two catchments at different elevations yields an apparent Arrhenius activation energy of 18.4 kcal/mol (77.0 kj/mol), much higher than most laboratory values. This finding supports recent suggestions that hydrolytic weathering of silicate minerals may consume carbonic acid and thereby remove atmospheric carbon dioxide mo...

The effect of watershed spatial scale on chemical weathering is inadequately known for subtropical environments. In order to determine the relationship between watershed scale and weathering chemistry, the Enoree River basin was sampled at seven different spatial scales ranging from second-order watersheds smaller than 2 km^2 to a sixth order watershed of 1840 km^2. The second-order watersheds ...

Climate variables including temperature, rainfall intensity, acidity, and lithological properties are among the most important factors affecting rock weathering. However, relative contribution of these four on weathering, especially chemical is still unclear. In this study, we carried out a series weathering-leaching simulations types badland sediments under controlled conditions two levels aci...

The weathering hypothesis suggests that early childbearing is an adaptive mechanism for disadvantaged young women, especially African Americans, who believe that their health status may decline as they move through adulthood. Implicitly, weathering assumes that these young women use contextual clues to formulate the likelihood of their own future adult health. We propose a simple yet, to date, ...

The composition of igneous rocks in the continental crust has changed throughout Earth's history. However, the impact of these compositional variations on chemical weathering, and by extension on seawater and atmosphere evolution, is largely unknown. We use the strontium isotope ratio in seawater [(87Sr/86Sr)seawater] as a proxy for chemical weathering, and we test the sensitivity of (87Sr/86Sr...

Several operative limitations are involved in the quantitative evaluation of damage processes. To plan an intervention, the assessment of the state of conservation appears incomplete without a realistic estimation. Stone and brick and above all sculptured surfaces and paintings need characterization, quantification, interpretation and rating of the weathering. In this field the use of non destr...

The long-term carbon cycle is vital for maintaining liquid water oceans on rocky planets due to the negative climate feedbacks involved in silicate weathering. Plate tectonics plays a crucial role in driving the long-term carbon cycle because it is responsible for CO2 degassing at ridges and arcs, the return of CO2 to the mantle through subduction, and supplying fresh, weatherable rock to the s...

The mineral weathering ability of 45 bacterial strains belonging to the genus Collimonas and coming from various terrestrial environments was compared to that of 5 representatives from the closely related genera Herbaspirillum and Janthinobacterium. Using glucose as the sole carbon source in a microplate assay for quantifying the release of iron and protons from biotite, all Collimonas strains ...

Weathering pro®les developed on organic carbon-rich black shales were studied to examine the loss and degradation of organic matter (OM) during weathering and its role in the geochemical carbon cycle. Analysis of weathered shales reveals between 60 and nearly 100% total organic carbon (TOC) loss in highly weathered samples relative to initial, unweathered TOC content. Pyrite loss coincides with...