Ann: Salamander-1 Short Flow Test , page-11

Guild. As usual your questions are excellent because you do your homework in thinking carefully and realistically. Not being familiar with the location I really can?t answer all of them.

Some general comments to note: Preperforated liners are not cemented in. Fluids can therefore normally still exude from any point on the rock surface, percolate along the narrow gap and exit through a perforation into the well. There may be different hole to space ratios according to choice of design but this does not (or should not) limit the flow. The slot sizes are likely to be quite large (~10 to 15 mm) and are not going to be clogged up by the small particles encountered. I doubt that simple debris is the problem. Such liners can be removed without great damage but not done lightly.

What they will do depends on the exact nature of their situation to which I am not privy. Direct scrubbing on sandstone could have rapid effects but then we don't know how far the drilling fluids have penetrated into the formation. Dropping the pressure gradient into the well would encourage flows back into the well and tend to wash out the micro pores in the neighbourhood of the surface over a period of some days. It is hard to know how aggressive a method should be employed. Chemical methods will be a ready consideration although to get a chemical reaction you have to be able to have a mixing effect or flow into the pores but this is where the clogging is. Chemical methods are good where you have a layer deposited onto a surface. Reversing the pressure direction seems to me the simplest solution but they will have a routine check list of procedures.

So much for my suggestions from a remote distance!

Juke