|
|
|
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
1 Cooperative Institute for Research in Environmental Sciences and Department of Geological Sciences, University of Colorado, Boulder, Colorado 80309-0216
2 Department of Earth Sciences, 6105 Fairchild Hall, Dartmouth College, Hanover, New Hampshire 03755
3 William Lettis & Associates, Inc., 1777 Botelho Drive, Suite 262, Walnut Creek, California 94596
Gravitational body forces (i.e., buoyancy forces) have come to be seen as critical to the evolution of orogens. Nevertheless, constraining the role of body forces in specific geologic scenarios is made difficult by the substantial number of poorly constrained physical parameters needed to fully relate forces to deformation. By separating the calculation of buoyancy forces from the calculation of the resulting deformation, models based on relatively simple descriptions of the lithosphere can yield geologically useful constraints. Among these are the importance of paleoelevation in driving syn- and postcontractional extension and in localizing contractional strain. Although such phenomena have been considered in more complex models of continental deformation, the simpler analysis presented here clearly establishes first-order limits on lithospheric structures and paleoelevations consistent with buoyancy-driven deformation. In the early Cenozoic Great Basin of the western United States, we show that the low elevations inferred in much of the geologic literature are inconsistent with a body-force origin for observed extensional tectonism. East of the Colorado Plateau, localization of Laramide deformation coincides with pre-Laramide subsidence of the Western Interior seaway. This subsidence prestressed the lithosphere, making the Southern Rocky Mountains the weak link in responding to regional compressional stress.
This article has been cited by other articles:
![]() |
F. M. Phillips Geological and hydrological history of the paleo-Owens River drainage since the late Miocene Geological Society of America Special Papers, January 1, 2008; 439(0): 115 - 150. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.P. PLATT From orogenic hinterlands to Mediterranean-style back-arc basins: a comparative analysis Journal of the Geological Society, March 1, 2007; 164(2): 297 - 311. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. W. Horton and C. P. Chamberlain Stable isotopic evidence for Neogene surface downdrop in the central Basin and Range Province Geological Society of America Bulletin, March 1, 2006; 118(3-4): 475 - 490. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. W. Horton, D. J. Sjostrom, M. J. Abruzzese, M. A. Poage, J. R. Waldbauer, M. Hren, J. Wooden, and C. P. Chamberlain Spatial and temporal variation of Cenozoic surface elevation in the Great Basin and Sierra Nevada Am J Sci, December 1, 2004; 304(10): 862 - 888. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. House, B. P. Wernicke, and K. A. Farley Paleo-Geomorphology of the Sierra Nevada, California, from (U-TH) /He Ages in Apatite Am J Sci, February 1, 2001; 301(2): 77 - 102. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. J. Ebinger, T. Yemane, D. J. Harding, S. Tesfaye, S. Kelley, and D.C. Rex Rift deflection, migration, and propagation: Linkage of the Ethiopian and Eastern rifts, Africa Geological Society of America Bulletin, February 1, 2000; 112(2): 163 - 176. [Abstract] [Full Text] [PDF] |
||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |