In theory caprocks should have the function of a sealing for gases and fluids preventing them migrating upwards. This is a topic for underground nuclear waste storage, CO2 storage, oil and gas deposits, underground storage of fluids and gases as an energy storage.
There is a lot of research going on on this field e.g.:
Article Self-sealing of pre-cracked callovo-oxfordian claystone: Imp...
Preprint Time-Lapse 3d Imaging and Modelling of Acid-Rock Interaction...