A New Method to Investigate Rheology of Zechstein Salt at Rest through Inverting the Sinking of Stringer Fragments.

There is a heated debate about the long-term rheology of salt at rest. As many researches show, pressure solution creep and dislocation creep mechanisms dominate mechanical behavior of salt. We summarize the database of researches of salt rheology for the first time. A new method is used to evaluate salt rheology through inverting the gravitational sinking of anhydrite inclusions (also called 'stringers') embedded in Zechstein salt at rest during the Tertiary. Seismic data can be used to compare with numerical model of sinking stringer. Results show that under the control of dislocation creep, the fragments has almost no movement but under the control of pressure solution creep, the fragments will sink obviously through the salt section during a few Ma (some fragments can sink hundreds of meters and touch the presalt). In conclusion, through inverting the sinking of stringer fragments the long-term Zechstein salt rheology can be investigated and dislocation creep dominates its deformation during Tertiary. [ABSTRACT FROM AUTHOR]