I doesn't. It should, but it doesn't.
Level 53 in Generation 1.
Venusaur can only learn Earthquake through TM26 Earthquake.
It doesn't learn Earthquake through level up, but it can learn it through the use of the Earthquake TM.
Aggron can learn earthquake by using the TM on it.
Camerupt learns Earthquake at level 49.
Grotle is not able to learn the move Earthquake by leveling or by TMs. It's evolved form Torterra is able to learn Earthquake at level 32.
Metagross can only learn Earthquake with the use of a TM.
Nidorina cannot learn Earthquake by any method.
First you need a kabuto then level it up to level 40 to have it evolve to kabutops.
Rhyhorn will learn earthquake at level 52. However, if you evolved it at level 42 into Rhydorn you will have to wait 6 levels later than normal to learn earthquake.
he dont learn it
Level 32.