The richer a channel of communication is, the more information the person on the receiving end of the communication is receiving. Verbal communication is always richer than non-verbal communication, because the listener can pick up more information than what he or she is being told. This is done by looking at facial expressions and gestures, and listening to the tone of voice used. A conversation, whether held face to face or over video-conferencing, is an extremely "rich" form of communication.
A blog would be considered to be of "medium" richness, because the writer is generally free to express him/herself openly, and the turns of phrase used can be very insightful.
A spreadsheet full of data or a general ledger are considered to be about the "lowest" in terms of channel richness. The information you have is the data, and there is no way to gain anything further from that information.
When addressing a workplace conflict, I certainly wouldn't do this by means of a spreadsheet! The best way to address a workplace conflict in its preliminary stages would be to open the channels of communication as much as possible. This would mean a face to face meeting with the person or people involved. This is particularly important if one was acting as a mediator between two members of staff who had been involved in a conflict with one another. The more information (both verbal and non-verbal) that can be given, received and shared, the better.