Stage 1:
Rainwater (purple) moves downward through faults or fractures in the rock and mixes with briny water (blue) deep in the rock.
Stage 2:
When the two waters mix, the chemistry changes and allows the water to dissolve the rock.
Stage 3:
The mixing zone becomes deeper in the rock as uplift occurs. The upper part of the cave drains and becomes air-filled while cave development is still occurring below.