In a recent unit application (attached) for the Spider Field, Chesapeake split the Haynesville into an Upper Haynesville Zone and Lower Haynesville Zone. The Upper HZ would correspond to the Bossier Shale Formation while the Lower HZ would be the Haynesville Shale Formation. Chesapeake may have taken this action voluntarily or under pressure as an original unit application for a single combine Haynesville Zone was delayed and then wihdrawn. Chesapeake noted the current application has opposition and Will-Drill & Frank Expl have presented alternatives.
The hearing in Baton Rouge is scheduled for Feb 1st and Chesapeake stated they have a lease expiration on 2/9/11. A Haynesville Shale well has been permitted for the section but not spudded.
Splitting the Haynesville Zone in this manner would allow both the Bossier Shale and Haynesville Shale to be fully developed in the section without seeking waiver of the minimum 660 ft spacing requirement between wells.
S7-T12N-R15W, U HA RA SUTT Unit & L HA RA SUTT Unit, Chesapeake, Logansport Field, DeSoto Parish
Chesapeake, Fisher 7 #H1 Well, Serial #242406, S6(7)-T12N-R15W
Les, do you see any implications of this other than ease of drilling restrictions for the operators?
Are the two shale formations separated enough they wouldn't interfere with each other?
Could existing wells be re-drilled with horizontal and vertical legs off the main lateral into other nearby formations?
PG, there is an adequate layer of low quality shale rock between the two target formation layers to avoid interference.
I don't follow your second question because you don't drill vertical legs off horizontal laterals. Operators only drill horizontal laterals in the Haynesville Shale as an extension of the vertical section of the wellbore. Rarely do operators use existing vertical wellbores because the original casing would normally be inadequate for drilling the horizontal lateral required for Haynesville Shale producers.
Legs off lateral..
Maybe think of branching like centipede legs only not so many legs or say a fish bone pattern. And if they could go left or right off the main line, why not up or down, perhaps gradual angles rather than sharp right angles. Be something if they could just run one lateral down the middle of a section and then branch out from that lateral to drain it all.. Guess that isn't something that's possible, huh?