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Selected Works of Susanne U. Jänecke
Article
Evolution of a Late Cenozoic supradetachment basin above a flat-on-flat detachment with a folded lateral ramp, SE Idaho
Geological Society of America Field Guide (2005)
  • A. N. Steely
  • Susanne U. Janecke, Utah State University
  • S. P. Long
  • S. C. Carney
  • R. Q. Oaks Jr.
  • V. E. Langenheim
  • P. K. Link
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Abstract
Uplift and exposure of the Bannock detachment system and the synextensional
basin fi ll deposits of the Salt Lake Formation provide a unique exposure of the threedimensional
geometries of a low-angle normal fault system and the stratal architecture
of the overlying supradetachment basin. Within this system, structural and
stratigraphic analyses, outcrop patterns, tephra geochronology, and geological cross
sections document several important relationships: (1) the Bannock detachment system
developed above the Sevier-age Cache-Pocatello culmination and resembles the
Sevier Desert detachment in its geometry, structural setting, and kinematic evolution;
(2) the Bannock detachment system initiated and slipped at low angles; (3) fl aton-
fl at, ramp-fl at, and lateral ramp geometries, as well as excision, can signifi cantly
affect the hanging wall deformation style due to the shallow depth (~2–4 km) of the
Bannock detachment fault during late stages of slip; (4) late Miocene–Pliocene tuffaceous
synrift deposits of the Salt Lake Formation record deposition in a supradetachment
basin, display an unroofing sequence, and a three-stage evolution that includes
pre-translation, translation, and breakup phases. Recycled pre-translation and translation phase deposits are diagnostic of this evolution; and (5) beginning in mid- to
late Pliocene time, high-angle, north-striking Basin and Range faults disrupted and
dismembered the Bannock detachment system.
Keywords
  • Late Cenozoic,
  • supradetachment basin,
  • Idaho
Disciplines
Publication Date
January 1, 2005
Citation Information
Steely, A. N., Janecke, S. U., Long, S. P., Carney, S. C., Oaks, R. Q Jr., Langenheim, V. E., and Link, P. K., 2005, Evolution of a Late Cenozoic supradetachment basin above a flat-on-flat detachment with a folded lateral ramp, SE Idaho, in Pederson, J., and Dehler, C. M., eds., Interior Western United States: Geological Society of America Field Guide 6, p. 169-198, doi: 10.1130/2005.fld006(08).