'ArtM72' pid='59816' datel Wrote:Pet - Could they run a discovery well to Mule Deer from A4 pad?
Art- Mule Deer has apparently morphed from what they used to think. If you look at the GLJ report
http://tinyurl.com/lrjknkq (maps 4 & 5) you will see that what they formerly called Mule Deer was west of Elk and Antelope and the highest part was even higher than Elk and Antelope. Where the block actually contacts the Elk and Antelope blocks the Mule Deer block appears to be 500 - 600 meters lower than the Elk and Antelope blocks.
The above map does not look anything like the seismic cross section shown on the June 9, 2015 presentation http://tinyurl.com/q2lzmbq chart 23. This cross section shows all of Mule Deer to be deeper than Antelope with part of Mule Deer being below Antelope. I do not know how this seismic line was made or which part of the three structures the seismic line crosses. So on a North/South basis I can not tell which part of the Antelope structure Mule Deer lies below. I can not tell if it is below Antelope-4.
As I mentioned elsewhere it may be difficult to drill through the Antelope structure and into the Mule Deer structure. If we drill through the gas bearing part of the Antelope zone it will be over pressured at the top and we will still have to fight the lost circulation zones if we use the required heavy mud. If we drill below the Antelope gas/water contact the reservoir pressure is very near a normal gradient so heavy mud would not be required and we might not need heavy mud. Such a well will probably require a revised casing program so that we can set casing both above the Antelope limestone and again above the Mule Deer limestone. The Mule Deer, being deeper, will be a higher pressure zone than Antelope so the lost circulation zones in the Antelope limestone will have to be cased off before drilling into the Mule Deer limestone. If the Mule Deer zone contains gas it would be able to flow up the hole and into any lower pressure lost circulation (high permeability) zone in the Antelope limestone. This would be what is sometimes referred to as an under ground blow out and it is a risk that we can not afford to take. So the casing program must be designed to protect us against that eventuality.