for Mud rock and its pore water study under different conditions kindly follow Classical Book of Garrels and Thomsons   or   Garrels and Crist..  Chemical kinetics and Activity study are well described and  may be useful for equilibrium study.

Dear Mr. Saxena,

could you specify your literature tip (title of the book)?

Thank you

Garrels, RM and Christ CL 1965.Solutions, Minerals and Equilibrium , Harper and Row , Newyork, 

Thank you, Mr. Saxena.

How about some more recent references that will help you think about caveats?

Hendry, M. J., S. L. Barbour, J. Zettl, V. Chostner, and L. I. Wassenaar. “Controls on the Long-Term Downward Transport of δ2H of Water in a Regionally Extensive, Two-Layered Aquitard System.” Water Resources Research 47, no. 6 (2011): n/a–n/a. doi:10.1029/2010WR010044.

Harrington, Glenn A., W. Payton Gardner, Brian D. Smerdon, and M. Jim Hendry. “Palaeohydrogeological Insights from Natural Tracer Profiles in Aquitard Porewater, Great Artesian Basin, Australia.” Water Resources Research 49, no. 7 (2013): 4054–4070. doi:10.1002/wrcr.20327.