Since rocks are aggregates of mineral particles, the effect of mineral microstructure on macroscopic mechanical behaviors of rocks is inneglectable. Rock samples of four different particle shapes are established in this study based on clumped particle model, and a sphericity index is used to quantify particle shape. Model parameters for simulation in PFC are obtained by triaxial compression tes...

The study area is located about 110 kilometers southeast of Mashhad and approximately 40 kilometers southeast of Fariman. The area is considered to be a part of the central Iran zone. It includes metamorphic rocks with different protoliths consisting of pelitic, carbonate and quartz - feldspathic rocks. The metamorphism in the study area is considered to be a contact regional metamorphism with ...

this paper presents the new geochemical isotopes sr and nd, and the mineralization data for the south neyshabour volcanic rocks located in ne iran. based on the chemical classifications, the studied rocks are basaltic trachy andesite, trachy andesite, trachyte, and trachy dacite in composition. all the analyzed volcanic rocks display enrichment in light rare earth elements (lree) relative to th...

The study area is located in the central Iranian tectono-magmatic zone, which is known for its world-class IOA-type Iron ore deposits. The Advanced Space borne Thermal Emission and Reflection Radiometer (ASTER) and Landsat Enhanced Thematic Mapper Plus (ETM+) image-processing techniques, were used in satellite imagery through conventional and also modern processing methods including band ratios...

We have studied the syn-kinematic very low-grade metamorphism in a polyphase Variscan deformed region using X-ray diffraction techniques. Two phases of regional metamorphism are related to their respective episodes of penetrative deformation in the southern Central Iberian Zone. The data obtained suggest that the rocks did not reach metamorphic equilibrium, but strain favoured the progress of m...

Diamictites, especially those deposited before the break-up of Gondwana in the Late Carboniferous and Permian, have recently been suggested to represent ejecta deposits from large comet or meteorite impact events. This is in contrast to the commonly held interpretation that these rocks represent glaciomarine sedimentary deposits. To test this controversial hypothesis, we carried out a detailed ...

The physico-chemical properties of serpentine soils lead to strong selection of plant species. Whereas many studies have described the serpentine flora, little information is available on the fungal communities dwelling in these sites. Asbestos minerals, often associated with serpentine rocks, can be weathered by serpentine-isolated fungi, suggesting an adaptation to this substrate. In this stu...

Fibrous tremolite is a mineral species belonging to the amphibole group. It is present almost everywhere in the world as a natural contaminant of other minerals, like talc and vermiculite. It can be also found as a natural contaminant of the chrysotile form of asbestos. Tremolite asbestos exposures result in respiratory health consequences similar to the other forms of asbestos exposure, includ...