We measure acoustic impedance, Z=c*d
Pressure will increase the density of water and the speed of sound. The speed of sound is SQRT(K/density), while K is also pressure depending. Water is not very compressible especially with 50% solids. I think in the end we might have a similar effect on gamma ray then on our probe: the density increases slightly with the pressure increase. We are going to test it when we perform the 300 bar test next month. But when the customer takes a sample and measured the density under atmosferic conditions and at another temperature, this could give an interesting discussion on site. This is a good reason for having a flow meter embedded in the log, so see deviations in the comparison with the lab. Normally these deviations are due to faulty sample taking and faulty Marcy scale.
In our chemical sensors, we measure speed of sound and temperature very accurately. In increased pressure will have effect on the mg/l range, which can influence the process when not incorporated in the chemometry models. Honestly, we never had to do this until now, but we would be able to.