The growth of vein fill

 



We use analogue and hydrothermal experiments to better understand the sealing of fractures. A first pilot study on quartz sealing of a quartzite at hydrothermal conditions were done with Eric Tenthorey at Australian National University, Canberra, Australia.
Anlogue experiments run in different types of see-though machines under the microscope. Below you see some examples, where a few mm wide fracture is sealed during advective transport from left to right. Growth is epitaxially on existing seed crystals at the upper and lower side, which mimick the fracture walls.

Link to the original site of Chris Hilgers

The role of grain boundaries in substructure development

 

In see-through experiments of deforming crystals under optical microscopes, it is possible to observe in near real-time processes such as grain boundary migration, fluid inclusion migration and the evolution of grain boundary fluids. These movies are part of the PhD-thesis of Joyce Schmatz (RWTH Aachen University). For more information, have a look at http://www.ged.rwth-aachen.de/Ww/peop... or http://www3.interscience.wiley.com/jo... .
In this movie the microstructural process is grain boundary migration recrystallization accompanied by dynamic grain growth. Please note the dynamic wetting angle with variations at leading and trailing surface. This experiment is also shown in Fig. 4b of http://dx.doi.org/10.1016/j.jsg.2009.... . The solid phase is camphor and the fluid is ethanol.


See-through deformation experiment with camphor (solid) and ethylene glycol (liquid). Please note grain boundary sliding of three adjacent camphor grains (upper left) and subgrain rotation recrystallization (lower right). Temperature is 85 ºC, strain rate is 1.4e-06 s-1. See also our article in the JMG and this preprint of our article to be published in CMP.

Link to the original site of Joyce Schmatz