Zion Oil & Gas Inc (ZNOG)

[tisdal]

Posting here so I can get back to it

Still researching this article but wanted to share

This is what caught my eye.

Well 23/26b-15 was planned primarily to appraise Jurassic sands below 15,700 ft. The Jurassic formations were expected to be overpressured to ±17.6 lbm/gal mud weight equivalent (MWE) at a temperature of 350°F. A short (±150-ft) lower-Cretaceous interval was predicted to overlay the Jurassic. In previous wells, where this lower-Cretaceous zone was absent, 18-lbm/gal gas-condensate kicks had been taken in the upper-Cretaceous limestone only 80 ft above the Jurassic. We believed that the formation pressures within the upper Cretaceous changed from±9.5 lbm/gal to±18 lbm/gal MWE over an interval of 300 to 1,000 ft. Two previous casing shoes set only 300 ft above the known kick zone had failed to provide sufficient seat integrity to penetrate the kick zone safely. As a result of this previous experience, locating the last intermediate casing shoe deep enough to provide adequate seat integrity, but shallow enough to avoid encountering the kick zone, was of critical importance to the success of the well.