Technology-Driven Approach To Develop Shale Gas in Saudi Arabia
Authors: Carpenter Chris 
Published: October 2016

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 172695, “Technology-Driven Approach To Develop Shale Gas in Saudi Arabia,” by Kirk M. Bartko and Brian Coffin, Saudi Aramco, and Roberto Tineo, Schlumberger, prepared for the 2014 SPE Middle East Oil and Gas Show and Conference, Manama, Bahrain, 8–11 March. The paper has not been peer reviewed.

Shale-gas resources were explored in Saudi Arabia by adopting a “technology-driven” approach against the US-based approach that might be termed the “factory” or “statistical” approach. The technology-driven approach and the customized work flow applied in this project have minimized the time required to understand the reservoir and apply the appropriate technologies. To date, this work flow has been used and calibrated with single-well analysis.

Introduction

The technology-driven approach to acquiring data was accomplished by maximizing data collection and developing a customized work flow to rapidly incorporate lessons learned for the next wells drilled. The overall challenge was to perform the assessment quickly and execute operations efficiently because of the quick drilling program with multiple rigs working.

Typically, a resource rock is evaluated, tested, and produced with individual tools and optimized by a statistical approach because of the number of wells drilled and completed in the area. In the study case, the well is an exploration well 1500 km away from the oilfield infrastructure with no offset-well information to support evaluation of the well. The approach was to build a single functioning model, combining a basin resource work flow with a hydraulic fracture- design work flow. The foundation pieces for this model must contain, at minimum, the following:

Core: Acquiring a core is essential because rock properties are required in geology, petrophysics, geomechanics, drilling, and fracturing. Both resource and bounding layers need to be included in this work.

Petrophysics: Logging programs need to deliver all data for the models and to be recalibrated on the basis of core and performance of the well.

Geology: A depositional model is critical because tectonism influences the trapping potential of the source rock. Recalibration is performed on the basis of the core and petrophysics.

Geomechanics: Both isotropic- and anisotropic-based models need to be constructed for drilling and stimulation requirements. The models need to integrate static core data and dynamic logging data, recalibrated with vertical well stress testing through microfracturing, if possible.

Drilling: Geomechanics is necessary for proper landing and drilling of the horizontal well along with the proper construction of the completion to handle pump rates and pressure.

Stimulation modeling: The model needs to be built on geological information of the area, and petrophysical and geomechanical data. The model should also incorporate mechanical limitations on the basis of completion capabilities such as maximum treating pressures or poor cementbond logs.

Microseismic: This provides an effective stimulation volume. The process needs to be integrated into the stimulation execution in realtime mode.

Production Data: A simplistic production model should be developed initially to understand production declines associated with stimulated volumes and fracture geometries. Model complexity increases with additional data.