Microstructures and Fabric
Compiled by Monica Bruckner at the Science Education Resource Center (SERC), Carleton College.
The following visualizations illustrate microstructures, rock fabrics, and the processes by which they form. Visualizations include simple animations, experimental models, visual output from numerical models, as well as static diagrams and photos. We also have additional structural geology visualization collections
Microstructures and Deformation Mechanisms (more info) This is the first in a series of lectures for a microstructures short course. These illustrated lecture notes introduce the topic of microstructures and discuss a variety of deformation mechanisms and processes. Some topics include point defects, dislocations, kinking, twinning, grain boundary sliding, and deformation mechanism maps and rheology. The notes also include links to further references. This resource is part of the Teaching Petrology collection. http://serc.carleton.edu/NAGTWorkshops/petrology03/index.html
Grain shape and crystallographic fabric development (more info) This site contains lecture notes from a short course on microstructures. The topic presented is grain shape foliation, which is defined as the preferred alignment of elongate grains. Processes that affect the development of a grain shape foliation are discussed, along with crystallographic preferred orientations, the grain size vs. stress relationship, and dislocation creep regimes in quartz aggregates. The notes are well illustrated, and links to further references are provided. This resource is part of the Teaching Petrology collection. http://serc.carleton.edu/NAGTWorkshops/petrology03/index.html
Analogue Microstructural Modeling at the University at Albany, SUNY (more info) This site contains 15 time-lapse QuickTime movies that show the experimental deformation behavior of octachloropropane. This compound shows similar microstructures to those found in quartzite, and thus is a nice analog for the deformation of rocks. The movies illustrate cataclastic deformation, grain boundary opening, formation of subgrains, subgrain boundary formation and grain boundary migration, ribbon formation, grain growth at zero strain rate, and grain boundary migration during high temperature deformation.
Deformation Microstructures in Quartzo-Feldspathic Rocks (more info) This site contains a collection of photomicrographs and accompanying descriptions of naturally and experimentally deformed rocks. These images illustrate microstructures resulting from a variety of deformation processes that are operative in the crust. Rock types include quartz-rich rocks, feldspar rocks. quartzofeldspathic rocks, pyroxenites, diabases, mantle rocks, and polyphase rocks. Each image has text describing the photomicrograph. A reference list is also provided.
3-D Animation of Dislocation Glide (more info) This website displays an animation of edge-screw dislocation glide in 3 dimensions. The animation is short and clear, and will be helpful to students trying to visualize this somewhat complicated process.
Formation of a stylolite (more info) This webpage features a quick animation that demonstrates the formation of a stylolite, a microstructure that resembles a suture. The site enhances a student's understanding of this mechanism with its concise visualization.
Dislocation Glide (more info) This animation from Monash University shows the process of dislocation glide in two dimensions. The animation shows what it would look like if we could zoom in on a single grain of sand, down to the scale of individual atoms.
Stress, Strain and Structure (more info) This volume of the Journal of the Virtual Explorer contains 19 papers in both html and pdf formats. Topics include microstructures, rheology, microfabrics, Mohr circles, natural deformation and deformation experiments. Some of the articles contain animated graphics and slide sets.