Upper trigram
☵
Water · Kan
Danger and depth.
FamilyMiddle son
ElementWater
Hexagram 48 of 64
☵☴ The Well
The source that does not move but nourishes all.
Lower trigram
☴
Wind · Xun
Gentle penetration.
FamilyEldest daughter
ElementWood
The image
Water above, Wind below.
Water over Wind: danger and depth meeting gentle penetration.
That combination is the whole meaning of hexagram 48. Nothing about it is arbitrary — change either trigram and you get a different hexagram with a different reading, which is why the 64 form a system rather than a list.