It makes sense that GPS works without data capability. I guess my real question is, how does my carrier (Verizon) treat that data coming from the satellite?
It's a different signal and a different receiver. Receiving GPS signals has nothing to do with your carrier. Note that your carrier can triangulate your rough position without the onboard GPS sending them "here I am" data, and that your GPS will work better when using WiFi and cellular receivers to know what it's closest to.
If my GPS works even if my talk plan and data plan are disabled, then I will structure my phone's survival apps to maximize the capabilities of GPS. Satellite communication is likely to be most reliable type of communication on my phone, followed by text, then email, then talk.
GPS is a one-way signal. The satellites broadcast their precise location and the precise time. By listening to the differences in the time signals from multiple satellites your GPS device (iPhone or whatever) can figure out where it is. The trick is getting maps on your device that work without a data connection.
The current version of iTopoMaps seems like it's stable, so I'm putting it back on my list.