tourmaline can be found as an accessory mineral in a variety of rocks including leucogranite, pegmatite, quartz veins, and metamorphiccountry rocks in hajiabad-dehgah area in se of boroujerd city. tourmaline in pegmatites is coarse-grained, subhedral to euhedral, anddisplays strong to moderate pleochroic blue rimmed by olive green. in contrast, tourmalines from leucogranite, quartz-veins, and h...

The composition of continental subduction-zone fluids varies dramatically from dilute aqueous solutions at subsolidus conditions to hydrous silicate melts at supersolidus conditions, with variable concentrations of fluid-mobile incompatible trace elements. At ultrahigh-pressure (UHP) metamorphic conditions, supercritical fluids may occur with variable compositions. The water component of these ...

[1] Geothermal activity is common at the foot of the Higher Himalaya near the Main Central Thrust (MCT), Nepal Himalaya. We have sampled hot springs along a 150 km stretch of the Himalayan front and find that they carry large fluxes of CO2 derived from metamorphic reactions. Hot spring fluids are saturated with CO2, have [DIC] from 1.3 to >100 mmol kg 1 and have dCDIC values from 13% to +13%(PD...

One view of the metamorphic subduction system supposes that coupled deformation and prograde/metasomatic reaction between the chemically enriched slab and the depleted mantle wedge promotes the formation of complexly hybridized lithologies along the slab/mantle interface. This type of model is based upon direct observations of the structure and petrology of high-P/T metamorphic complexes (e.g.,...

The world-class Macraes orogenic gold deposit (∼10Moz resource) formed during the late metamorphic uplift of a metasedimentary schist belt in southern New Zealand. Mineralising fluids, metals and metalloids were derived from within the metasedimentary host. Helium and argon extracted from fluid inclusions in sulphide mineral grains (three crush extractions from one sample) have crustal signatur...