vault/geology on channel

[crotwell]

Current items that describe the recording environment, like vault and geology, exist at the station level, but as a station is a 1 km cube, these could vary from channel to channel. Obvious example would be a station that has a surface seismometer in a "barrel" vault along with a seismometer in a borehole, where vault should probably be "borehole".

Is it worth allowing some of the these attributes to exist on the channel, with the idea that if all are the same, then just use station level attributes, but if different place on channel level.