Characteristics and environmental aspects of slag: A review

Representative samples (as defined in section 1.5, chapter 1) from the economic zone of the lower Mn orebody, including the lithostratigraphic zones M, C and N, from eight drill cores in the study area (Fig. 1.4) were selected for whole rock chemical analysis to represent all stages of supergene alteration. Although the X-zone has very good manganese grades, it was not used for modeling purposes, as it is eroded over large parts of the suboutcrop area below the Kalahari Formation and very few drill cores intersect strongly supergene altered X-zone. Among the 8 selected drill cores Rex 16, 44 and 85 represent the geochemistry of unaltered braunite lutite protore, Rex 70, 71 and Rex 74 represent weakly supergene, and Rex 2 and 24 strongly supergene altered braunite lutite (Fig. 4.1). It is important to note that for comparative purposes and mass balance calculations, it was necessary to link supergene altered samples to unaltered reference samples of the same lithostratigraphic zone from different core intersections (Table 4.1). To assure compatibility, unaltered reference samples were selected from drill cores located in close proximity to the altered drill cores to be evaluated. Consequently, samples from REX 16 are reference for REX 2, 24 and 74, and samples from REX 85 are used as reference for REX 70 and 71 (Fig.4.1).

Geochemistry (地球化学・前半)

Orogenic architecture of the Mediterranean region and kinematic reconstruction of its tectonic evolution since the Triassic

How Large Igneous Provinces affect global climate, sometimes cause mass extinctions, and represent natural markers in the geological record

Oxalate production by fungi: significance in geomycology, biodeterioration and bioremediation

Saharan dust transport to Europe and its impact on photovoltaic performance: A case study of soiling in Portugal

Three different yellow and red ochre pigments geological sources from Alentejo—Terras rossas, schist units and weathered iron ore deposits—were studied by elemental and phase analysis complemented with Munsell and CIELAB colour parameters. Central aims were to underline the mineralogical and chemical distinctiveness of natural pigment sources and establish a connection between local geology and use of specific colour pigments in traditional lime wash mural paintings. According to the chemical composition the Fe abundance is 6 times higher than average crust values. The Terras Rossas are characterized by higher Ca contents. In yellow and red schists, phyllosilicates are major minerals, so pigments from these units are enriched in K and Rb. Besides Fe, the pigments from weathered ores are enriched in metals like Pb, As, Cu, and Zn, which can be used as fingerprints.

/pdf/yellow-and-red-ochre-pigments-from-southern-portugal-4ika1op5jt.pdf

Yellow and red ochre pigments from southern Portugal: Elemental composition and characterization by WDXRF and XRD

Oxalate biofilm formation in mural paintings due to microorganisms – A comprehensive study

The basal surfaces of phyllosilicate minerals have been widely studied, whereas the edge surfaces have received little attention. However, in order to simulate complete clay particles at the atomic level, the modeling of edge surfaces becomes crucially important, and such surfaces are likely to be far more active. We used a combination of quantum and potential based techniques to evaluate the structure of the edge surfaces of pyrophyllite and their interaction in an aqueous environment. These include {110}, {100}, {010}, {110}, {130}, and {130}. We found that the CLAYFF force field is an effective model for reproducing the DFT results. Furthermore, the results show that, for this notorious natural hydrophobic clay, all edge surfaces show hydrophilic behavior and that the precise structure of water above these surfaces is influenced by both the presence of hydroxyl groups and under-coordinated surface Al atoms; this will impact both geological processes where natural clays are involved and processes wher...

Toward Modeling Clay Mineral Nanoparticles: The Edge Surfaces of Pyrophyllite and Their Interaction with Water

http://cathedral.lnec.pt/publicacoes/c9.pdf

José Mirão

Papers

Saharan dust transport to Europe and its impact on photovoltaic performance: A case study of soiling in Portugal

Yellow and red ochre pigments from southern Portugal: Elemental composition and characterization by WDXRF and XRD

Oxalate biofilm formation in mural paintings due to microorganisms – A comprehensive study

Toward Modeling Clay Mineral Nanoparticles: The Edge Surfaces of Pyrophyllite and Their Interaction with Water

Microscopic characterisation of old mortars from the Santa Maria Church in Evora