Objective was gas prospect in the Kujung limestone, known to be over-pressured in East Java area.
Word on the street is that Lapindo had significant open hole (about 3,000 ft ?) below casing shoe when they took a kick on 29 May while drilling (into the Kujung?) at 9,297 feet.
Massive well kick, flowed hot water to surface completely unloading the well.
When well shut-in, underground blow out occurred, possibly breaking down casing shoe. Water surfaced about 200 meters from the rig (the “mud volcano”).
Flow rate reported to be greater than 300,000 Bbls / day
SOP (and BPMIGAS-approved drilling program?) calls for intermediate protective casing at about 8,500 ft. Casing never run.
Relief well operations not yet successful.
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I don’t know what is fact and what isn’t. But I do look as warily upon “official data” as I do on “word on the street”.
I Haven’t looked at the full paper published recently, but from this article, and the previous information I have seen (including bullet points above), I still think it likely that the root cause for the mud flow was an underground blowout.