Title : A simple practical technique for the determination of the fracture pressure gradient In Sirte Basin Area
Abstract:
Knowledge of the magnitude of Geo-pressures like pore, fracture and overburden pressures, are vital especially during drilling, completions and stimulations. In many occasions, problems like lost circulation could have been avoided if reliable techniques for calculating geo-pressures had been employed in the well planning, mud weight calculation and casing design. However, one of the main problems of estimating the fracture pressure gradient is the lack of data. In fact, drilling engineers generally face situation where only leak-off test data (frequently having questionable results) are available. This problem is normally the case of drilling shallow formations where very little information is collected.
This paper presents a new practical method to estimate fracture pressure gradient, which has advantage of using only the knowledge of leak-off test data. The proposed method has been compared with the most published methods such Eaton, Hubbert and Zhang. That derived methods are mainly based on wave velocities, Biot coefficient (Laboratory measurements) . The method has been applied in many reservoirs in Sirte Basin ( shallow and deep reservoirs) Area with very good results.
