Vanadian-chromian tourmaline and vanadian muscovite in contact-metamorphosed carbonaceous rocks, Primorye, Russia

Transmission electron microscopy of muscovite alteration of tourmaline

Partially sericitized tourmaline from a pegmatite was investigated using high-resolution transmission electron microscopy (HRTEM). Fine-grained muscovite crystals form extensive narrow veinlets preferentially developed along the {110} and {100} cleavages of tourmaline, indicating that a cleavage-controlled alteration mechanism was dominant. HRTEM images show that tourmaline-muscovite interfaces...

A Metamorphosed Olivine-rich Aggregate in the Cv3 Carbonaceous Chondrite

A metamorphosed olivine-rich aggregate was found in the least metamorphosed CV3 Y-86009. Although such aggregates were observed in CV3 Mokoia and Vigarano, and CO (CM) Acfer 094 [1-3], their precursors and formation mechanism have not been fully understood. Here, we report mineralogical observations of an olivine-rich aggregate in the Y-86009. The olivine-rich aggregate is embedded in matrix. I...

Thermally Metamorphosed Antarctic CM and CI Carbonaceous Chondrites in Japanese Collections, and Transformation Processes ofPhyllosilicates

Spectral reflectance properties of carbonaceous chondrites 4: Aqueously altered and thermally metamorphosed meteorites

Department of Geography, University of Winnipeg, 515 Portage Avenue, Winnipeg, Manitoba, Canada R3B 2E9 Astromaterials Research and Exploration Science Office, NASA Johnson Space Center, Mail Code KR, 2101 NASA Road 1, Houston, TX 77058-3696, USA Department of Geological Science, Brown University, Box 1846, Providence, RI 02912-1846, USA Department of Space Studies, University of North Dakota, ...

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...