Surface and subsurface characterisation of salt pans expressing polygonal patterns

Abstract. The data set described here contains information about the surface, subsurface, and environmental conditions of salt pans that express polygonal patterns in their surface salt crust (Lasser et al., 2020b; https://doi.org/10.5880/fidgeo.2020.037). Information stems from 5 field sites at Badwater Basin and 21 field sites at Owens Lake – both in central California. All data were recorded during two field campaigns from between November and December 2016 and in January 2018. Crust surfaces, including the mean diameter and fluctuations in the height of the polygonal patterns, were characterised by a terrestrial laser scanner (TLS). The data contain the resulting three-dimensional point clouds that describe these surfaces. The subsurface is characterised by grain size distributions of samples taken from depths between 5 and 100 cm below the salt crust and measured with a laser particle size analyser. Subsurface salinity profiles were recorded, and the groundwater density was also measured. Additionally, the salts present in the crust and pore water were analysed to determine their composition. To characterise the environmental conditions at Owens Lake, including the differences between nearby crust features, records were made of the temperature and relative humidity during 1 week in November 2016. The field sites are characterised by images showing the general context of each site, such as pictures of selected salt polygons, including any which were sampled, a typical core from each site at which core samples were taken, and close-ups of the salt crust morphology. Finally, two videos of salt crust growth over the course of spring 2018 and reconstructed from time lapse images are included.