Gas Initially in Solution

If gas is still in solution then the test technique will depend on utilizing the principle that gas under a compressive process goes to equilibrium more quickly than the expansion sequence. The explanation proposed is that the diffusion gradient is generally larger from a bubble into a nonsaturated fluid than it is when gas is moving from a 

Generalized cross section of an ocean sedimentary/chemical environment. (From Rau, G., and Chaney, R.C., Triaxial testing of marine sediments with high gas contents. In Advanced Triaxial Testing of Soil and Rock, ASTM STP 977, Donaghe, R.T., Chaney, R.C., and Silver, M.L., eds., American Society for Testing and Materials, Philadelphia, PA, 338-352,1988. Reprinted with permission from ASTM.) 

---