Dyanna Czeck's Research
My research is in the area of structural geology focused on studying strain, deformation fabric formation, and rheology in naturally deformed rocks. I primarily study shear zones, tectonites including deformed conglomerates, and granite emplacement fabrics at a variety of scales. Most of my work combines field studies with other techniques like petrographic studies, electron backscatter diffraction (EBSD, to measure crystallographic orientations in rocks), FTIR (to measure water content in deformed rocks), mathematical modeling, or magnetic fabric studies. Over the last several years, I’ve had the opportunity to study rocks in Spain (Catalonia, Andalusia), Scotland (NW Highlands, Islay), Canada (Ontario, Nova Scotia), and the USA (Wisconsin, Utah, California, Minnesota). Students are collaborators on most of my research projects.
Some Current Projects:
Rheology and conglomerates, tillites, and other fragmental rocks:
Due to natural variations in the response to strain, heterogeneous deformed rocks such as conglomerates provide natural laboratories to observe the effect of rheology on deformation. By exploiting the natural contrasts and our ability to measure strain within the conglomerates, we address the processes of deformation partitioning within heterogeneous rocks. I have worked on several collaborative projects that look at rheology in deformed conglomerates (and similar rocks). In one project with Dr. Basil Tikoff (UW-Madison) and many students, we analyzed the deformation evolution across a strain gradient using strain analysis, electron backscatter diffraction (EBSD), and petrographic analysis. Field areas for this project include the Gem Lake Shear Zone in the Sierra Nevadas and the Seine Conglomerates from the Rainy Lake region in Ontario. We published two papers on this topic so far (Horsman et al., 2008 in GSA Bulletin and Czeck et al., 2009 in Journal of Structural Geology). In a related project, I am working with Dr. Adolph Yonkee (Weber State University) and many students to study the interactions of fluids with increasing strain across a deformed tillite in northern Utah using Fourier Transform Infrared (FTIR) and XRF techniques to document mineralogical and fluid changes (see Yonkee et al., in press at Journal of Structural Geology).
Relationships between intrusions and deformation can be complex and interesting! I am working on a collaborative project with Dr. Elena Druguet from the Universitat Autònoma de Barcelona studying small syntectonic intrusions in the Superior Province (Rainy Lake region of Ontario/ Minnesota border) and the Cap de Creus region in northeastern Spain. We are looking at the complex field geometries formed with multiple intrusions during a prolonged deformation event (see Druguet et al., 2008 in Precambrian Research and Druguet et al., 2012 in Geology). I also work on deformation in large plutonic bodies associated with orogenesis. In one collaborative project with Dr. Basil Tikoff (UW-Madison), we and our students are studying pluton emplacement and deformation in the Northwest Highlands of Scotland.
Anastomosing shear zone geometries:
Shear zones in nature often have anastomosing (braided) geometries, and these geometries have been called upon to explain strain localization, mechanical abilities to continue deformation, and segregated fluid flow in the crust. However, the processes of development and geometries of the anastomosing strands have yet to be understood. I am working on a project with Dr. Prajukti Bhattacharyya (UW-Whitewater) and several students to study the geometries of small shear zones associated with the Mountain Shear Zone in northeastern Wisconsin (see Bhattacharyya and Czeck, 2008 in Geosphere and DeVasto et al., 2012 in Computers and Geosciences). In a related project, I am working with Dr. Jordi Carreras from Universitat Autònoma de Barcelona (Spain) and several other colleagues and students. We are studying anastomosing geometries of shear zones that occur in rigid gabbroic bodies within a broader deformation zone in the Rainy Lake region of Ontario (see Carreras et al., 2010 in Journal of Structural Geology).
I have always been interested in relating deformation features of rocks in the field to predictions from strain modeling. Currently, I am working with Dr. Carlos Fernández (Universidad de Huelva, Spain) and Dr. Manuel Díaz Azpiroz (Universidad Pablo de Olavide, Spain) to model transpression and link the modeling to field structures in the South Iberian Shear Zone (Spain) and the Rainy Lake region (Canada).