Looked at this further. That icon appears next to the Bluetooth icon when an app is requesting the iPad's location.
If you go to 'Settings', 'General', 'Location Services' there are a list of apps that are enabled to use the iPad's location. Apps that have requested the location within the last 24 hours have that icon next to them.
So you should be able to identify the 'usual suspects'. In my list I have TuneIn (the Internet radio player that uses the iPad's location to find 'local' Internet radio stations) and (of course) 'Maps', because I opened it to find out what that icon meant!! I also have two other apps that are allowed to access the iPad's location, but have not done so in the last 24 hours.
The ability of an app to access the iPad's location can be turned on and off on an app-by-app basis here.
Tim
Scotland