A set of alumino-silicate glasses with SiO2-Al2O3-Na2O-CaO compositions was investigated using Raman and NMR spectroscopy techniques by classical molecular dynamics, in order to study the structural modifications which occur when CaO progressively replaces Na2O Al2O3 SiO2. The effect a gradual increase content also studied. Al always 4 coordinated for all studied, including peraluminous glasses...

More than 50 conspicuous tephra beds occur in the Kanguk Formation of SW Banks Island. Their glass shards are remarkably well preserved and permit comprehensive characterization offering potential for reliable, precise correlation Upper Cretaceous sedimentary rocks across three major depocentres Arctic Archipelago adjacent northern continental margin: Sverdrup, Banks, Beaufort-MacKenzie basins....

The Sierra de Guasayán (Eastern Sierras Pampeanas, Argentina) is formed by low to medium grade metamorphic rocks intruded Cambrian metaluminous (La Soledad quartz-diorite), slightly peraluminous (Guasayán, El Escondido and Martirizado granodiorite plutons), strongly (Alto Bello granodiorite) granitoids of the Pampean magmatic arc. Chemical compositions amphibole, plagioclase, biotite, titanite ...

The Tuscany Magmatic Province consists of a Miocene to Pleistocene association wide variety rock types, including peraluminous crustal anatectic granites and rhyolites, calcalkaline shoshonitic suites ultrapotassic lamproites. In addition the magma types already recognised, occurrence new, distinct type at Capraia Elba islands in mafic enclaves San Vincenzo rhyolites has been suggested by recen...

The East Kunlun Orogen (EKO) in the northern Tibetan Plateau records two continental collisional orogenic events and magmatism early Paleozoic Mesozoic. However, possible magmatic additions to crust growth of EKO different tectonic stages orogeny have been overlooked. Three phases plutons from Xiangride-Kuhai area east chosen for detailed investigation results are reported here. oldest suite (S...

Mesozoic granitic magmatism in Northeastern Jiangxi, China is of tectonic significance for the evolution South Block. Whole-rock geochemical and zircon U–Pb geochronological Lu–Hf isotopic data Zhuxi granites Jingdezhen area Jiangxi were presented. The are composed granodiorite, biotite granite, two-mica granite. Zircon LA–ICP–MS analyses indicated emplacement at 159–147 Ma. characterized by a ...

There are three sex ratio strategies (SRS) in nature-male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton's local mate competition (LMC) and Clark's local resource competition (LRC) separately explained the observed deviations from the seemingly u...

Breast density, as visible on mammograms, is generally assessed as the occupied percentage of the breast and is a risk factor for breast cancer. Various studies have looked into the causation and alteration of relative density but the relation of a determinant with a relative measure does not allow a direct etiologic interpretation. It was our goal to compare the effects of known determinants o...

The terms ratio scale, apparently first introduced by Stevens (1946, 1951), and ratio scaling, apparently first introduced by Krantz (1972) but closely related to previous phrasing, denote different but interrelated things. Although Krantz was very clear on the matter,' the similarity of the terms seems to invite confusion and confounding. My goal here is to explicate some aspects of the differ...