Abstract

In the Northwest German Basin of Central Europe, Late Triassic interaction of normal faulting and salt diapirism during regional extension in subsalt basement locally initiated lateral flow of surface-piercing salt in namakiers (salt glaciers). Using seismic sections and variance attribute maps derived from high-resolution three-dimensional seismic data, we show that when a syndepositional fault cuts a near-emergent diapir crest, the caprock carapace was breached, opening a pathway for salt extrusion. The fault escarpment and the adjacent fault-induced depression allowed focused gravity-driven downward flow of salt across the land surface (a namakier) and its subsequent preservation and encasement in continental (arid redbed) sediments. Geodynamically there is an apparent distinction between the compressional setting of modern namakiers in the arid deserts of Iran and the fault-intersected extensional setting of stacked Keuper namakiers. Stacked namakiers preserved in thicknesses that are seismically resolvable are interpreted to indicate hyperarid conditions in Keuper time. The climate was typical of the highly continental Late Triassic Pangaean supercontinent as it rifted and sagged to form the incipient Atlantic Ocean.

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