20251120 16594600 1.0 TRUE Porosity This data layer comprises porosity measurements on the upper 2 cm of seabed sediments. Bottom sediments were collected using either a Smith McIntyre grab or a Box Core. Bulk sub-samples (6.5 ml) of surface sediment (0-2 cm) were extruded into vials which were then frozen. Porosity was determined by calculation of the wet volume as a percentage of the total volume, after freeze drying and correction for seawater salts. The accuracy of the wet/dry measurements were greater than 1%. The precision of the volume measurements were greater than 2%. © Commonwealth of Australia (Geoscience Australia) 2016. This product is released under the Creative Commons Attribution 4.0 International Licence. http://creativecommons.org/licenses/by/4.0/legalcode