This came up to me early summer and I told them no to the seismic survey. The broker told me that he would contact the mineral rights owner(s) and if they gave permission, they would do the survey anyway. They only offered $200, we own 20 acres, but I told them a flat no. He said "...these things sometimes end up in court" and I said I was comfortable with that possibility. If push came to shove, I would have allowed it. They did a few surrounding properties and left. I like the other advice to get everything in writing by someone that has authority to do make the agreements.
Andrew
Andrew