Partially open grain and phase boundaries as fluid pathways in metamorphic and magmatic rocks

‘ballen Silica’ in Impactites and Magmatic Rocks

Introduction and background: Ballen silica, in the modification of α-quartz (‘ballen quartz’) or α-cristobalite, has been regarded as an impactcharacterstic microscopic feature for decades. The report of ballen silica in impact melt rocks from the Mien impact structure (Sweden; the impact melt rocks were formerly considered as rhyolites) was the first description of ballen silica in impactites ...

Groundwater in Sedimentary, Metamorphic and Volcanic Rocks

Structural phase transformations in metallic grain boundaries.

Structural transformations at interfaces are of profound fundamental interest as complex examples of phase transitions in low-dimensional systems. Despite decades of extensive research, no compelling evidence exists for structural transformations in high-angle grain boundaries in elemental systems. Here we show that the critical impediment to observations of such phase transformations in atomis...

Magmatic and Metamorphic Fluids in Pegmatite Development: Evidence from Borujerd Complex, Iran

The Borujerd complex of western Iran is composed of intrusions and their surrounding contact aureole, with, pegmatites and quartz veins. Pegmatites differ in mineralogy, origin and age, and two groups can be distinguished. The Older Pegmatites (about 120 Ma age) intruded contact metamorphic rocks from the early magmatic stage, while the Younger pegmatites (52-70 Ma age) formed during the late m...

Two types of tourmaline with igneous and metamorphic origin in metamorphic rocks of north Golpayegan, Isfahan province

The Muteh-Golpayegan metamorphic complex consist of different metamorphic rocks including pelitic, semi-pelitic, carbonate, quartz-feldspathic and basic metamorphosed rocks. The metapelitic rocks include chlorite schist, biotite schist, garnet schist, staurolite schist, kyanite schist, sillimanite schist and andalusite schist. The semi-pelitic rocks contain higher amounts of quartz and lower am...