A new simple method to estimate fracture pressure gradient
Projecting safety and more economic wells calls for estimating correctly the fracture pressure gradient. On the other hand, a poor prediction of the fracture pressure gradient may lead to serious accidents, such as lost circulation followed by a kick. Although these kind of accidents can occur in any phase of the well, drilling shallow formations can offer additional dangers caused by shallow gas kicks because they have the potential of becoming a shallow gas blowout leading sometimes to the formation of craters. This paper presents a new method to estimate fracture pressure gradient. The proposed method has the advantage of (1) using only the knowledge of leakoff test data and (2) being independent of the pore pressure. The method is based on a new concept called pseudo-overburden pressure, defined as the overburden pressure a formation would exhibit if it were plastic. The method was applied in several areas of the world, such as the US Gulf Coast (Mississippi Canyon and Green Canyon), with very good results.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 390070
- Journal Information:
- SPE Drilling and Completion, Vol. 11, Issue 3; Other Information: DN: Presented at the 1994 SPE international petroleum conference and exhibition, October 10--13, Veracruz (MX); PBD: Sep 1996
- Country of Publication:
- United States
- Language:
- English
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