The following diagram shows the W3C PROVenance Working Group's Technical Reports, how they link into the prov namespace, and how the prov namespace composes the six OWL definitions provided for each Technical Report. Clicking the image will get you to a PDF version.
We used Solution 2.2 to organize the PROV namespace. These were the running notes while we were implementing it.
The PROV FAQ outlines the six ontologies that are aggregated for the prov namespace. This description was a response to a public review comment during the final stages of the working group.