Metamorphism and partial melting of ordinary chondrites: Calculated phase equilibria

Effects of Metamorphism on the Valence and Coordination of Titanium in Ordinary Chondrites

KINETICS AND VOLATILIZATION OF SiC AND S i O 2: IMPLICATIONS FOR METAMORPHISM OF UNEQUILIBRATED ORDINARY CHONDRITES;

Introduction: Constraints on thermal histories and physical conditions during the formation of unequilibrated ordinary chondrites (UOCs; petrologic type 3) are largely based on inferences from more equilibrated varieties (types 4-7). In this study, we explore the possibility of a more direct indicator based on the observation [1, 2] that abundances of diamond and SiC decrease systematically in ...

Impact-induced frictional melting in ordinary chondrites: A mechanism for deformation, darkening, and vein formation

available online at http://meteoritics.org 1521 © Meteoritical Society, 2003. Printed in USA. Impact-induced frictional melting in ordinary chondrites: A mechanism for deformation, darkening, and vein formation C. H. VAN DER BOGERT,1* P. H. SCHULTZ,1 and J. G. SPRAY2 1Department of Geological Sciences, Brown University, Providence, Rhode Island 02912, USA 2Planetary and Space Science Centre, De...

Pyrometamorphism and partial melting of shales during combustion metamorphism: mineralogical, textural, and chemical effects

Eocene shales metamorphosed by a naturally ignited coal seam in the Powder River Basin, Wyoming record a continuum of mineralogic and textural changes from relatively unaltered shale to melt developed during pyrometamorphism. Samples collected along a section 2 m in length, corresponding to a temperature range of approximately 1300 ~ C, were examined optically and by XRD, SEM, and STEM. The low...

Metamorphism and Melting in an “unmetamorphosed” Mesosiderite

Introduction: The mesosiderites are amongst the most enigmatic of all the meteorite groups and their formation is not fully understood. Evidence taken from both the metal and silicate portions indicates that they have a multi-stage formation history [1,2]: 1. Initial crystallization and cooling of silicates, followed by brecciation on the surface of the parent body 2. Metal-silicate mixing, som...