Compressional and Shear Interval Velocity Modeling to Determine Formation Pressures in an Oilfield of SW Iran

Mohammadi

J Petrol Explor Prod Technol

et al. 2023

Accurate knowledge of pore and fracture pressures is essential for drilling wells safely with the desired mud weight (MW). Overpressure occurs when the pore pressure is higher than the normal hydrostatic pressure. There is a challenge regarding the pressure studies domain in an oilfield in SW Iran, where lack of geo-mechanical data limits exact mud window calculation. Also, the reservoir generally consists of carbonate rocks and contains no shale interbeds, so mechanical stratigraphy based on Gamma ray could not be applied. This study is to provide safe drilling considering MW to prevent the flow or loss in the vicinity of the new wells in the studied field. In this research, the formation pressures and mud window models are determined by combining geostatistical, intelligent, and conditional programming models and compared with real data. The conditional programming was also used to correct small out-of-range data. The highest correlation between the final effective pressure and velocity cube was observed in lower Fahliyan Formation with 0.86 and Ilam with 0.71.The modeled MW difference ranged between 2.5 and 30 PCF. Also, the maximum modeled MW is 150 PCF in the upper Fahliyan Formation. Heavy mud of more than 130 PCF is suggested for drilling the Khalij member and continues to the end of stratigraphy column. Best observed correlation comparing the drilled and modeled MW, especially achieved in the Fahliyan reservoir Formation with more than 100 PCF and the Ilam Formation with 80–100 PCF. Finally, 3D formation pressures are presented and recommended for further safe drillings.

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Section: Introductionmentioning

confidence: 99%

“…Fig.3Sample of seismic data section with formation top, depth domain seismic sections, and location of exploratory wells in South Azadegan Field(Kianoush et al 2022) …”

mentioning

confidence: 99%

Determining the drilling mud window by integration of geostatistics, intelligent, and conditional programming models in an oilfield of SW Iran

Mohammadi

J Petrol Explor Prod Technol

et al. 2023

show abstract

“…Consequently, reduce drilling risk and related costs in these areas is achieved. In addition to pressure, other factors such as lithology also affect the speed of seismic waves; therefore, the use of available geological information and well logs can essentially prevent errors in estimating the pressure of the formation, especially in carbonate formations (Ganguli and Sen 2020;Ganguli et al 2016;Ganguli et al 2018;Kianoush et al 2022;Radwan 2021).…”

Section: Introductionmentioning

confidence: 99%

Determining the drilling mud window by integration of geostatistics, intelligent, and conditional programming models in an Oilfield of SW Iran

Mohammadi

et al. 2023

Preprint

Accurate knowledge of pore and fracture pressures is essential for drilling wells safely with the desired mud weight (MW). Overpressure occurs when the pore pressure is higher than the normal hydrostatic pressure. There is a challenge regarding the pressure studies domain in an oilfield in SW Iran, where lack of geo-mechanical data limits exact mud window calculation. Also, the reservoir generally consists of carbonate rocks and contains no shale interbeds, so mechanical stratigraphy based on Gamma ray could not be applied. This study is to provide safe drilling considering MW to prevent the flow or loss in the vicinity of the new wells in the studied field. In this research the formation pressures and mud window models are determined by combining geostatistical, intelligent, and conditional programming models and compared with real data. The conditional programming was also used to correct small out-of-range data. The highest correlation between the final effective pressure and velocity cube was observed in lower Fahliyan Formation with 0.86 and Ilam with 0.71.The modeled MW difference ranged between 2.5 and 30 PCF. Also, the maximum modeled MW is 150 PCF in the upper Fahliyan Formation. Heavy mud of more than 130 PCF is suggested for drilling the Khalij member and continues to the end of stratigraphy column. Best observed correlation comparing the drilled and modeled MW, especially achieved in the Fahliyan reservoir Formation with more than 100 PCF and the Ilam Formation with 80-100 PCF. Finally, 3D formation pressures is presented and recommended for further safe drillings.

show abstract

“…Furthermore, a new fast inversion algorithm was performed to prospect the gravity anomaly profiles, like evaluating the depth, amplitude coefficient, and shape parameter of target structures for simple geometric bodies. This new inverted model parameters approach mainly used the analytical signal of the gravity anomaly profile data in Slovakia, Cuba, and India (Essa, Abo-Ezz, et al, 2021;Kianoush et al, 2022). The manta ray foraging optimization (MRFO) is a novel swarm algorithm developed by Zhao et al (2020) .The optimization process mimics the foraging behaviors of manta rays for the solution of physical problems.…”

Section: Introductionmentioning

confidence: 99%

Tilt Angle Filter Effect on Noise Cancelation and Structural Edges Detection in Hydrocarbon Sources in a Gravitational Potential Field

Farajkhah²,

et al. 2023

Preprint