Sheathfolds in rheomorphic ignimbrites

  title={Sheathfolds in rheomorphic ignimbrites},
  author={Michael J. Branney and Tiffany L. Barry and Martha M. Godchaux},
  journal={Bulletin of Volcanology},
Structural reappraisal of several classic rheomorphic ignimbrites in Colorado, Idaho, the Canary Islands and Italy has, for the first time, revealed abundant oblique folds, curvilinear folds and sheathfolds which formed during emplacement. Like their equivalents in tectonic shear-zones, the sheathfold axes lie sub-parallel to a pervasive elongation lineation, and appear as eye structures on rock surfaces normal to the transport direction. With the recognition of sheathfolds, ignimbrites… 
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