Learner's definition of DOMINANT. 1. [more dominant; most dominant] : more important, powerful, or successful than most or all others. The university has/plays a dominant [=major] role in the local economy. Money is the dominant [=main] force in consumer societies. The company is now dominant in its market.
Shale is a fine-grained sedimentary rock that can have high porosity, yet can be nearly impermeable due to the poorly interconnected voids.hale is a fine-grained sedimentary rock that can have high porosity, yet can be nearly impermeable due to the poorly interconnected voids.
No rock is completely impermeable, but some porous rocks like shale and pumice are mostly impermeable, because the pores are not interconnected, thus not allowing fluids or gases to pass through them. This is why shale makes a good cap-rock, and pumice floats instead of sinking.