External shapes, strain rates, and dynamics of salt structures

Research Article| March 01, 1986 External shapes, strain rates, and dynamics of salt structures M.P.A. JACKSON; M.P.A. JACKSON 1Bureau of Economic Geology, The University of Texas at Austin, Austin, Texas 78713 Search for other works by this author on: GSW Google Scholar C. J. TALBOT C. J. TALBOT 2Institute of Geology, University of Uppsala, S-751 22 Uppsala, Sweden Search for other works by this author on: GSW Google Scholar GSA Bulletin (1986) 97 (3): 305–323. https://doi.org/10.1130/0016-7606(1986)972.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation M.P.A. JACKSON, C. J. TALBOT; External shapes, strain rates, and dynamics of salt structures. GSA Bulletin 1986;; 97 (3): 305–323. doi: https://doi.org/10.1130/0016-7606(1986)972.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Salt structures continue to attract attention as petroleum traps and as storage vessels for wastes or fuels. Drawing on field studies, experiment, and theory, we examine the megascopic structure and large-scale dynamics of salt structures.Salt flowage can transform a tabular salt body into nondiapiric rollers, anticlines, and pillows; into diapiric walls, stocks, massifs, and nappes; and into extrusive domes and salt glaciers. These structures distort at widely variable strain rates of 10−8 s−1 to 1016 s−1, with a comparatively restricted range of dominant wavelengths of 7–26 km.Buoyancy is an ineffective diapiric mechanism unless the salt structure has pre-existing relief of at least 150 m beneath a denser overburden of terrigenous clastics. Differential loading is a far more effective mechanism in the early stages of diapirism and commonly results in asymmetric salt structures. Gravity spreading modifies the shape of salt structures with negative buoyancy. With a heat-induced density inversion, thermal convection may lead to internal circulation and stirring of a still-tabular salt body. At least four mechanisms may form broad bulbs on mature salt stocks. Consideration of the effective viscosity contrast between salt and its cover suggests that mature stocks may have stems much more narrow than is commonly envisaged.Salt tectonics is classified here on the basis of change of gravity potential energy that promotes or retards salt flow. Halokinetic movements can be initiated, succeeded, retarded, or accelerated by regional tangential forces that stretch, wrench, or compress sedimentary basins. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.