"Tenacious Earth" is not a recognized geological or scientific term. It's possible you're thinking of a different phrase, or it might be a term used in a specific context like a book, movie, or game.

To better understand what you're looking for, could you please provide more context? For example:

* Where did you encounter this phrase? (e.g., a book, website, conversation)

* What was the general topic or subject matter?

* Did the phrase have any specific connotations or meanings within that context?

With more information, I can help you find the answer you're looking for.