salt rivers and theories..., page-17

Matt_66...

There are wells in the region with production from zones that showed only 250 units during drilling...but typically wider rather than narrow intersections, which sort of backs your theory.

The difficulty we have here is that at such depths, we would have the mud weights fairly high...so many potential low pressure, or indeed low porosity hits may not record as anything more than very minor background gas.

This is why they get increases during tripping, as the mud pressures are eased off which reduces the pressure on the formations...and subsequently the forced being applied to push the gas back into their hosts!

The other consideration however is that when you stop mud circulation, the portion sitting beside the gas shows can be over-charged...that is, as the mud is just sitting and not circulating, more gas can mix in with the muds than when they normally pass by relatively quickly.

In this scenario, when circulation starts up gain, we see a short-term spike in the gas readings for that section of mud.

Generally speaking however, shorter stops for such things as adding drill strings result in less of a rise in background gas, whilst longer stops for such things as bit replacements can see much higher readings build up.

Remember though...at these depths and pressures, even modest "shows" could prove economic once tests are completed, but obviously the higher the pressure and flows...and background readings intersected...the more likely they are of being commercial.

It is entirely possible they have drilled 200ft of productive but low pressured (or low porosity) formation...as long as the gross pay zone is big enough, it may well be commercial.

We will not know of course until post hole testing.

Cheers!