It certainly is not to create some sort of pseudo-textbook - you will have textbook readings to do from book chapters to cover that.
This course website is simply to:
Offer guidance on thinking about topics. This may take the form of saying "read Chapter X from Book Y", or, read this article/report, or, do these suggested homework problems, etc.
Organize the course materials: data, documents, ...
Provide an easy to find location for reference materials you might use later, for example after you have graduated and moved on but might need to recall something related to near-surface geophysics (geol420.net; jasbinsek.link/geol4420).