Rudy Wenk joined the Department in 1967. His research is in crystallography, mineralogy, structural geology and rock deformation. Most recently (see research interests and publications), emphasis has been on understanding seismic anisotropy in the earth by investigating the development of preferred orientation under expreme conditions (temperature and pressure) with neutron diffraction, synchrotron x-rays and electron microscopy. The research is funded by NSF and DOE. He wrote an introductory mineralogy book, published by CambridgeUniversity Press. A new edition has appeared in 2016.

Mineralogy-Crystallography. Microstructures in minerals developing during deformation and phase transformations. In the past much work has been dedicated to feldspars, carbonates and perovskites. More recently cement minerals have become a fascinating topic of analysis (with Paulo Monteiro, Civil Engineering).

Anisotropy-Texture Development. Presently research emphasis is on investigating the development of preferred orientation in rocks and man-made materials. Close collaborations with materials scientists have been most rewarding. The approach is to balance modelling with experiments to better understand the development of anisotropy in the deep Earth. With diamond anvil experiments (mainly done at ALS and APS) materials can not only be subjected to high pressure and temperature, but simultaneously they can be deformed and texture development can be observed in situ. Anisotropy changes during phase transformations (e.g.olivine transforming to spinel and perovskite in the mantle, bcc iron transforming to hcp iron, trigonal quartz transforming to hexagonal quartz) are fascinating new topics that become available for investigations with new instrumental techniques. A new research emphasis is on quantification of preferred orientation in shales with synchrotron X-ray diffraction, relevant to seismic prospecting.

Field Investigations. Though most complex, natural rocks provide a lot of insight into basic mechanisms as well as a larger context for detailed studies. Presently fieldwork concentrates on the EasternPeninsular Ranges in Southern California with magnificent mylonites and a huge zone of pseudotachylites that appear related to ancient seismic activity. He is starting projects to investigate effects of shock deformation on quartz at meteorite impact sites as well as similar features in samples from the San Andreas fault drill core (SAFOD). Other projects continue in the central Alps and Japan. Fieldwork also provides an outlet for Rudy Wenk's hobby interests in mountain climbing and mountaineering.

Facilities. Rudy Wenk is maintaining a comprehensive Texture Laboratory with instruments (pole figure goniometers, an EBSP scanning electron microscope) and software (BEARTEX). Synchrotron X-rays play an increasing role in the quantification of microstructural features (ALS, APS and ESRF).

Support: The research is currently supported by NSF and DOE-BES.

Current Graduate Students:

Panod Viseshchitra

Chase Chandler

Michelle Devoe

Visiting Scholar:

Jingyi Huang from Beijing University

EPS 298. Directed Group Study for Graduates. Friday 2-4.

(currently by zoom)

Visit publication page and download papers

http://eps.berkeley.edu/~wenk/TexturePage/Publications/Wenk-Publications...

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