Present-day in-situ stresses in Southern Gulf of Suez, Egypt: Insights for stress rotation in an extensional rift basin

The in-situ stress fields are of great importance in the interpretation of tectonic features and the analysis of hydrocarbon systems. In this work, we determine the in-situ stress field, pore pressure, stress regime, and fracture gradient in the Hilal oil field at the southern Gulf of Suez, Egypt. Wireline logs of four wells and direct borehole measurements were used to analyze the pore-pressure and fracture gradients. Drilling-induced fractures and borehole breakouts, which were observed on fullbore microimages, were used to determine the orientations horizontal stress axes. The study revealed: 1) A maximum horizontal stress axis, SHMAX, with mean orientation of 150 degrees; 2) This stress orientation in Hilal oil field differs from the stress orientation in neighboring oil fields, and thus indicate stress rotations in the southern Gulf of Suez; 3) The determined stress orientations confirm the structural complexity of the southern sub-basin; and 4) The documented rotation of the present-day stress state in the southern sub-basin contributes to our understanding of the paleo-stress field interpretations in the Suez rift basin. The presneted analysis assists in drawing an updated stress field map of the tectonically active Rift Basin, and leads to better understanding of the neotectonics in an extensional rift basin.

Automated summary

This study determines the in-situ stress field, pore pressure, stress regime, and fracture gradient in the Hilal oil field in Egypt, revealing stress rotations and structural complexity in the southern Gulf of Suez. The findings contribute to understanding the paleo-stress field interpretations in the Suez rift basin.