Abstract Coal balls are carbonate concretions that preserve peat in cellular detail. Despite their importance to paleobotany, the salinity of coal-ball remains controversial. Pennsylvanian coal from Midland and Illinois basins contain echinoderms early high-magnesium calcite cement. Echinoderm skeletons reflect Mg/Ca ratio seawater which they grew. Here we show well-preserved North American mar...

Calcium leaching from cementitious materials into bentonite is a key process for the long-term alteration of cement–clay interfaces engineered barrier systems. Strong chemical gradients between cement and clay drive precipitation minerals such as calcium silicate hydrate (C–S–H) calcite. To analyze mineralogical porosity evolution at interface, composite specimens consisting paste mixed with va...

This paper aims at investigating the influence of partial replacement of Portland cement with ultrafine fillers compared to limestone powder on the durability and mechanical characteristics of concrete. For this purpose, ultrafine calcium carbonate materials with different specific surface areas of 9.7 and 15.1 m2/g and limestone powder (0.72 m2/g) were used. The results indicate that the ultra...

Alkali-activated slag is commonly used as a cement substitute to reduce the environmental footprint of construction materials. Nonetheless, use significant amount alkaline activators, such sodium silicate or hydroxide, can be detrimental in terms global warming potential impact. The aim this work complementary activators partial replacement and therefore activated binder. Calcium calcium carbon...

While the characteristics and origin of drusy calcite cement in carbonate deposits is well constrained literature, little attention paid to dolomite cement. Petrographic observations, stable isotopes, fluid-inclusion microthermometry suggest that Permo-Triassic conglomerate/breccia dolostone beds northern United Arab Emirates has precipitated as not by dolomitization The low ?18OVPDB (?9.4‰ ?6....