Physical Modeling of Structures Formed by Salt Withdrawal: Implications for Deformation Caused by Salt Dissolution

摘要: By creating 15 physical models, we investigated deformation above subsiding tabular salt, salt walls, and stocks. Dry quartz sand simulated a brittle sedimentary roof viscous silicone representing salt. The modeled diapiric walls had linear planforms rectangular, semicircular, triangular, or leaning cross sectional shapes; the stock was cylindrical. In models where source layer (or allochthonous sheet) initially tabular, gentle, flat-bottomed syncline bounded by monoclinal flexures formed zone locally removed. Above all diapirs, deformed an inner of steep, convex-upward reverse faults outer normal faults. extensional contractional zones were balanced. stock, conical, concentric fault comprised Sediments added both before (prekinematic) during (synkinematic) withdrawal. entirely prekinematic roofs, widened with time. Reverse propagated upward from corners withdrawing diapirs. New in footwalls faults, each nearer center deepening trough. Conversely, new successively outward sagging Synkinematic deposition retarded faulting, but pattern repeated; however, outward, whereas inward. conceptual suggest that dissolution forms similar structures to those physically for appropriate resemble natural Extension alone diapirs is not caused merely withdrawal dissolution, regional extension active diapirism.