the granites south of mashhad are located in the north-east of iran and occur in the suture zone between the binalud and kopeh dagh areas. these s-type granites are peraluminous with an upper triassic age and include intersecting pegmatites. these pegmatites are homogenous and show simple mineralogical combinations which include k-feldspars (microcline and orthoclase), plagioclase, quartz, mica...

• P contents of strongly peraluminous granites (SPGs) from 0-3500 Ma are compiled. Maximum SPGs increase after 720 Ma. concentrations in reflect temporal variability sedimentary abundances. Enhanced recycling into magmas occurs Neoproterozoic. Variable granite influences interpretation detrital zircon chemistry. Phosphorus plays an important role both surface biological cycles as a critical mac...

The diffusion of water in a peralkaline and a peraluminous rhyolitic melt was investigated at temperatures of 714–1,493 K and pressures of 100 and 500 MPa. At temperatures below 923 K dehydration experiments were performed on glasses containing about 2 wt% H2Ot in cold seal pressure vessels. At high temperatures diffusion couples of water-poor (\0.5 wt% H2Ot) and water-rich (*2 wt% H2Ot) melts ...

We present new viscosity measurements for melts spanning a wide range of anhydrous compositions including: rhyolite, trachyte, moldavite, andesite, latite, pantellerite, basalt and basanite. Micropenetration and concentric cylinder viscometry measurements cover a viscosity range of 10 to 10 Pas and a temperature range from 700 to 1650 °C. These new measurements, combined with other published da...

Containerless melting was employed to evaluate the influence of increasing ZrO2 additions on glass-forming ability peraluminous melts in magnesium aluminosilicate system. The saturation limit this oxide glasses along silica-cordierite join (SiO2–Mg2Al4Si5O18) is inversely proportional SiO2 content; however, a limited solubility melt-quenched silica exists (∼2 mol%). Peraluminous samples (partic...

Most Himalayan Cenozoic leucogranites are peraluminous magmas that have experienced various degrees of fractional crystallization. These characterized by relatively high heterogeneity in their elemental compositions. As the melt’s Zr/Hf ratio passes ∼20, there is an apparent change from positive to negative correlation between Zr (or Hf) and ratio. Nb/Ta ∼5, Nb first decreases then increases, b...

Biotite, the dominant ferromagnesian mineral in granitoid rocks, can be used to discriminate tectonic setting, magma types and magnetite- ilmenite series. In this study, we analyzed biotite with an electron microprobe (wavelength dispersion) from different granitoids. Intrusive rocks from Maherabad porphyry Cu-Au prospecting are meta-aluminous. Biotite from Maherabad are Mg-rich type and the ra...