Produced water density - PetroWiki

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The formation water density is defined as the mass of the formation water per unit volume of the formation water. Electronic densiometers can quickly determine the density with accuracy of / 0.00001 g/cm3 over a wide range of temperatures, although most oilfield data are reported at a 60 F reference temperature. In the past, density in metric units (g/cm3) was considered equal to specific gravity; therefore, for most engineering calculations, density and specific gravity were interchangeable in most of the older designs.[2] However, process simulation software used in modern facility design uses the true density or specific gravity of the water to avoid significant cumulative errors, especially when working with low-gravity heavy oils or concentrated brines. Thus, water samples taken for providing input to these programs must have accurate densities determined experimentally.