Page 106 - Fundamentals of Gas Shale Reservoirs

86 SEQUENCE STRATIGRAPHY OF UNCONVENTIONAL RESOURCE SHALES

Well B
0 1000 2000 3000

100ft

UW
MaW
H Well A
0 1000 2000 3000 4000 5000
MbW 100 ft
LW
McW is a ductile driling hazard. Well went into
MbW and couldn’t get back up into MbW (target). UW MbW
TD was called at 3400 ft. LVV
(1100 ft short of plan). IP 13 BPD and 1.0MMCFd. MaW H
Uneconomic.

The good and the bad for the woodford: 4500 ft lateral drilled in 3 days in MbW target
effect of lithology and stratigraphy (brittle). Entire operation TD’d in 34 days.
IP 360BPD and 1.7MMCFd. Economic well.
FIGurE 4.19 Stratigraphically targeted drilling within Woodford Brittle–Ductile couplets. In the upper figure, the well was drilled into the
brittle (MbW) horizon, but dipped into the ductile (McW) drilling hazard zone, leading to early well shut­in. In the lower figure, the well
was drilled into the ductile layer but was able to pull back into the brittle (MbW) layer and remain there, leading to a productive well. With
the permission of Killian (2012).

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