I'd really like to see a lithology log of the San Juan field. Where are the horizons of interest and where is the karst. I don't see us getting oil out of the karst if that is where we are losing circulation. And you don't want to pump concrete into your formation ... you'd never get any oil out. Ergo, I assume they are cementing up to the point of lost circulation, setting a plug above the karst and cementing the remainder of the casing above the plug, requiring us to perf the casing to complete the concrete job??  So, hopefully the zones of interest are all below the karst formation. The bit could be passing through a cavern for all I know, stalagtites and all ... pretty karsty. Oiljob

Maybe Max could send me a log.