a time to reflect & read the announcements, page-44

Hi DM,
Yes, Halliburton are the pros at this, but the fact remains that water based frac fluid was left in contact with the formation for an extended period of time, in normal circumstances this would have been flowed out. Even the most inhibited water based well bore fluids (ie super salt saturated, invert emulsions, polymer based fluids) will over time react with a shale formation to cause damage. That's why Oil companies will use a very expensive SOB (synthetic oil based) mud system if a reactive shale formation is to be left uncased for any length of time.