The mineralogy and chemistry of the less than 20μm fraction of marine sediments at Morphou Bay, north-west Cyprus, are presented to characterise fine-grained sediment supplies from basic and ultrabasic rocks of the Troodos Massif within a typological setting. The sediments comprise a mixture of smectite, illite, kaolinite and iron rich chlorite. They also contain amorphous iron oxides/hydroxide...

A method to simultaneously determine calcite surface area and content in soils has been developed. The proposed procedure is based on rates of CO2 production upon reaction of soil with buffered acid solutions under controlled conditions. A pressure transducer connected to a chart recorder allows determination of soil calcite dissolution rate, which is directly proportional to calcite surface ar...

The geochemical composition of foraminiferal tests is a valuable archive for the reconstruction of paleo-climatic, -oceanographic and -ecological changes. However, dissolution of biogenic calcite and precipitation of inorganic calcite (overgrowth and recrystallization) at the seafloor and in the sediment column can potentially alter the original geochemical composition of the foraminiferal test...

Research on argillite as a possible host rock for nuclear waste disposal is still an open subject since many issues need to be clarified. In the Underground Research Laboratories constructed for this purpose, a damaged zone around the excavation has been systematically observed and characterized by the appearance of micro-fissures. We analyse here -at nanoscale level- the calcite/clay assembly,...

Fly ash samples from the five steam electric power stations of the Lignite Center of Western Macedonia were used in this study. They consisted mainly of anhydrite, lime, quartz and amorphous material as well as feldspars, calcite, micas + clays, portlandite and gehlenite which were all present in minor amounts. Anhydrite, lime and portlandite in the fly ash samples diminished upon treatment wit...

ABSTR&CT Seven brickmaking clays from various geological horizons have been studied by differential thermal and X-ray methods. The minerals detected included kaolinite, illite, montmorillonite, chlorite, swelling chlorite, calcite and quartz, and rough estimates were made of the quantities present. For the same clays, deformation-under-load was measured at four different heating rates, and stre...

Ternary clay-based composite material (TCC), composed of lime, clay and sand, and usually modified with sticky rice and other organic compounds as additives, was widely used historically in Chinese construction and buildings due to its high mechanical performance. In this study, to gain an insight into the micromechanical mechanism of this cementitious material, the nanomechanical properties an...

Fired clay minerals rehydroxylate after firing, a phenomenon that causes the long-term mass gain and expansion seen in archaeological ceramics. During rehydroxylation, fired clay minerals react with H2O to form structural hydroxyl (OH). Recent models propose that rehydroxylation is described by a quartic root (t1/4) time dependence, which has led to a dating method based on the process (RHX, re...