The ability to drill exploration objectives safely and efficiently is controlled by knowledge of the available drilling margin. We present an application of operational geosciences for two recent exploration wells in Egypt and Syria where pore fluid pressure and fracture pressure models were built pre-drill to enable well design. While drilling the well, these models were updated in real-time (24/7) to make the right operational decisions. In addition, before drilling the more challenging well sections, learnings from shallower sections in the well were used to prepare a look-ahead assessment of the available drilling margin to select a strategy to drill the next section.

The two wells have in common that the presence of a narrow drilling margin was recognized early in the exploration phase such that proper data analysis could be completed pre-drill for the entire planned well trajectory. Furthermore, options for real-time data acquisition were investigated early such the right geoscience data could be acquired and interpreted during drilling for operational support.

Engineering, geosciences and communication form equally important components of narrow margin well execution. Real-time analysis of logging while drilling data, mud logging data and hydraulics data was used, as well as the intelligent deployment of managed pressure drilling technology, to make decisions such as adjustment of the drilling mud and selection of section depth (TD). A Communications Protocol was followed to assure that critical anomalies in the predicted drilling margin were efficiently communicated to the Drilling Supervisor for immediate operational response.

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