Hydrous Deformation and Recrystallization in Quartz: Characterizing Microstructural Evolution and Water Content Distribution

• Applicant: Professorin Dr. Lucie Tajcmanova
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 548014059

The mechanical behavior of the lithosphere under stress, particularly the role of water in influencing the deformation of minerals like quartz, is fundamental to our knowledge of plate tectonics, volcanic activity, and earthquake generation process. Recent studies underline the significant impact of water on the mechanical properties of lithospheric minerals, facilitating critical deformation processes and affecting recrystallization rates, grain boundary migration, and overall lithospheric strength. This project aims to delve into the complex interplay between H2O content and the microstructural evolution of quartz under hydrous conditions. The primary objectives are to constrain the kinetics of quartz recrystallization and grain boundary migration under hydrous conditions, experimentally investigate the conditions that promote recrystallization, refine the theoretical framework for grain boundary migration, and validate a new experimental methodology for studying quartz deformation. Through a series of a new kind experiments on natural quartzite materials, we intend to 1) analyze how water influences key microstructural processes, including grain boundary migration, grain growth, and recrystallization; 2) investigate the distribution of hydrogen in grains of differing microstructural origins; and 3) develop a new, more accurate grain boundary migration law for quartz to address the shortcomings of existing models. Our research will utilize a two-stage deformation-annealing experiment approach to induce transient microstructures, enabling the detailed measurement of water content distribution across different grain types. Additionally, the new experimental setup will offer fresh insights into microstructural evolution during deformation and annealing processes. The outcomes of this study are expected to enhance our understanding of water incorporation in quartz, the effects of water on recrystallization processes, and grain boundary migration, thereby providing valuable insights into the strain localization and strength of the lithosphere.

• DFG Programme: Research Grants
• International Connection: Israel
• Cooperation Partner: Dr. Yuval Boneh