{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/53821"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/53821","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"The Fries Fault near Riner, Virginia: an example of a polydeformed, ductile deformation zone","abstract":"The Fries Fault, a 1.2-2.3 km wide zone near Riner, is a major tectonic discontinuity in the Blue Ridge geologic province, characterized by progressive stages of continuous ductile deformation. Trending northeast with a shallow to moderate southeast dip, this fault juxtaposes Little River Gneiss on the southeast against Pilot Gneiss and the Chilhowee Formation to the northwest. A 0.8-1.2 km wide subzone of protomylonite within the Little River Gneiss grades into a 0.5-1.0 km wide mylonite subzone, the latter containing narrow bands of phyllotactic ultramylonite ranging in width from centimeters to tens of meters. Mylonitization is reflected by a marked reduction in grain size, elongation of quartz and fracturing of feldspar, all concomitant with the development of a mylonitic foliation (S<sub>m</sub>). Ductile deformation processes involving grain elongation, recovery and recrystallization, combined with chemical processes (primarily pressure solution), are the dominant strain-accommodation mechanisms in the formation of S<sub>m</sub>. Rocks within the fault zone have undergone four phases of Paleozoic deformation. An early S₁ foliation has been nearly completely transposed by S<sub>m</sub>(S₂), which dominates across most of the area. The development of S<sub>m</sub> was accompanied by a retrogressive metamorphism that altered basement rocks from lower amphibolite to greenschist facies. Chilhowee Group rocks remained at lower greenschist facies. Post-faulting deformation produced an S₃ crenulation cleavage associated with northeast trending, overturned F₃ folds. Subsequent refolding produced open, northwest trending F₄ folds. Although the bulk deformation is progressive simple shear, flattening is increasingly dominant during the later stages of deformation.","abstract_html":"The Fries Fault, a 1.2-2.3 km wide zone near Riner, is a major tectonic discontinuity in the Blue Ridge geologic province, characterized by progressive stages of continuous ductile deformation. Trending northeast with a shallow to moderate southeast dip, this fault juxtaposes Little River Gneiss on the southeast against Pilot Gneiss and the Chilhowee Formation to the northwest. A 0.8-1.2 km wide subzone of protomylonite within the Little River Gneiss grades into a 0.5-1.0 km wide mylonite subzone, the latter containing narrow bands of phyllotactic ultramylonite ranging in width from centimeters to tens of meters. Mylonitization is reflected by a marked reduction in grain size, elongation of quartz and fracturing of feldspar, all concomitant with the development of a mylonitic foliation (S&lt;sub&gt;m&lt;/sub&gt;). Ductile deformation processes involving grain elongation, recovery and recrystallization, combined with chemical processes (primarily pressure solution), are the dominant strain-accommodation mechanisms in the formation of S&lt;sub&gt;m&lt;/sub&gt;. Rocks within the fault zone have undergone four phases of Paleozoic deformation. An early S₁ foliation has been nearly completely transposed by S&lt;sub&gt;m&lt;/sub&gt;(S₂), which dominates across most of the area. The development of S&lt;sub&gt;m&lt;/sub&gt; was accompanied by a retrogressive metamorphism that altered basement rocks from lower amphibolite to greenschist facies. Chilhowee Group rocks remained at lower greenschist facies. Post-faulting deformation produced an S₃ crenulation cleavage associated with northeast trending, overturned F₃ folds. Subsequent refolding produced open, northwest trending F₄ folds. Although the bulk deformation is progressive simple shear, flattening is increasingly dominant during the later stages of deformation.","abstract_has_math":false,"creators":["Kaygi, Patti Boyd"],"institution":"Virginia Polytechnic Institute and State University","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Geological Sciences","degree_department":"Geological Sciences","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1979,"date_issued":"1979","date_published":"1979","updated_at":"2026-07-22T22:19:16Z","subjects":[],"languages":["en_US"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/53821","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Geological Sciences"]},{"key":"dc:creator","label":"Author","values":["Kaygi, Patti Boyd"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2015-06-26T20:54:59Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2015-06-26T20:54:59Z"]},{"key":"dc:date.issued","label":"Date","values":["1979"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Polytechnic Institute and State University"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Geological Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/53821"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The Fries Fault, a 1.2-2.3 km wide zone near Riner, is a major tectonic discontinuity in the Blue Ridge geologic province, characterized by progressive stages of continuous ductile deformation. Trending northeast with a shallow to moderate southeast dip, this fault juxtaposes Little River Gneiss on the southeast against Pilot Gneiss and the Chilhowee Formation to the northwest. A 0.8-1.2 km wide subzone of protomylonite within the Little River Gneiss grades into a 0.5-1.0 km wide mylonite subzone, the latter containing narrow bands of phyllotactic ultramylonite ranging in width from centimeters to tens of meters. Mylonitization is reflected by a marked reduction in grain size, elongation of quartz and fracturing of feldspar, all concomitant with the development of a mylonitic foliation (S<sub>m</sub>). Ductile deformation processes involving grain elongation, recovery and recrystallization, combined with chemical processes (primarily pressure solution), are the dominant strain-accommodation mechanisms in the formation of S<sub>m</sub>. Rocks within the fault zone have undergone four phases of Paleozoic deformation. An early S₁ foliation has been nearly completely transposed by S<sub>m</sub>(S₂), which dominates across most of the area. The development of S<sub>m</sub> was accompanied by a retrogressive metamorphism that altered basement rocks from lower amphibolite to greenschist facies. Chilhowee Group rocks remained at lower greenschist facies. Post-faulting deformation produced an S₃ crenulation cleavage associated with northeast trending, overturned F₃ folds. Subsequent refolding produced open, northwest trending F₄ folds. Although the bulk deformation is progressive simple shear, flattening is increasingly dominant during the later stages of deformation."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["The Fries Fault near Riner, Virginia: an example of a polydeformed, ductile deformation zone"]}]}],"canonical_facts":{"dc:contributor.department":["Geological Sciences"],"dc:creator":["Kaygi, Patti Boyd"],"dc:date.accessioned":["2015-06-26T20:54:59Z"],"dc:date.available":["2015-06-26T20:54:59Z"],"dc:date.issued":["1979"],"dc:description.abstract":["The Fries Fault, a 1.2-2.3 km wide zone near Riner, is a major tectonic discontinuity in the Blue Ridge geologic province, characterized by progressive stages of continuous ductile deformation. Trending northeast with a shallow to moderate southeast dip, this fault juxtaposes Little River Gneiss on the southeast against Pilot Gneiss and the Chilhowee Formation to the northwest. A 0.8-1.2 km wide subzone of protomylonite within the Little River Gneiss grades into a 0.5-1.0 km wide mylonite subzone, the latter containing narrow bands of phyllotactic ultramylonite ranging in width from centimeters to tens of meters. Mylonitization is reflected by a marked reduction in grain size, elongation of quartz and fracturing of feldspar, all concomitant with the development of a mylonitic foliation (S<sub>m</sub>). Ductile deformation processes involving grain elongation, recovery and recrystallization, combined with chemical processes (primarily pressure solution), are the dominant strain-accommodation mechanisms in the formation of S<sub>m</sub>. Rocks within the fault zone have undergone four phases of Paleozoic deformation. An early S₁ foliation has been nearly completely transposed by S<sub>m</sub>(S₂), which dominates across most of the area. The development of S<sub>m</sub> was accompanied by a retrogressive metamorphism that altered basement rocks from lower amphibolite to greenschist facies. Chilhowee Group rocks remained at lower greenschist facies. Post-faulting deformation produced an S₃ crenulation cleavage associated with northeast trending, overturned F₃ folds. Subsequent refolding produced open, northwest trending F₄ folds. Although the bulk deformation is progressive simple shear, flattening is increasingly dominant during the later stages of deformation."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/53821"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Polytechnic Institute and State University"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["The Fries Fault near Riner, Virginia: an example of a polydeformed, ductile deformation zone"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Geological Sciences"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:16Z"}