Micro-XRCT data sets of subflorescent salt crusts from evaporation of MgSO4 solution with 0.64 mol/L initial concentration

Abstract

This data set contains data of scans of three separated dry salt crusts that formed by evaporation of magnesium sulfate solution with 0.64 mol/L initial concentration from F32 quartz sand at 40%, 30%, and 20% saturation inside the sand packing. The cylindrical sample holder from polymethyl methacrylat (PMMA) had a diameter of 31 mm and a wall thickness of 5 mm. The crusts consisted of sand grains (F32, Quarzwerke Frechen, mean grain size 240 µm), solid salt (particularly magnesium sulfate tetra hydrate), and air. Other magnesium sulfate hydrates may have precipitated (i.e. magnesium sulfate hepta hydrate, hexa hydrate, mono hydrate). The scanned domain with a diameter of 11.76 mm and a resolution of 4 µm per voxel was located in the radial center of the crust. Details of the scan are listed in the process metadata. The reconstructed data is segmented into four phases, outside, void, salt, and sand (for details see below).