Viridien’s real-time rock data analysis optimises gas storage drilling

With gas and carbon storage activities expanding across the Middle East as operators pursue carbon reduction and energy efficiency goals, Viridien offers specialised geological analysis solutions for effective well placement in UBCTD

Underbalanced coil tubing drilling (UBCTD) technology is being utilised to re-enter existing vertical wells in depleted fields, allowing for the drilling of multiple horizontal legs, which significantly improves direct access to the reservoir. UBCTD lowers drilling costs and reduces formation damage, preserving permeability.

Specialised geological analysis is key for effective well placement in UBCTD. Advanced rock analysis of drill cuttings at the wellsite involves biosteering (microscopic fossil analysis), rock-typing, and visual porosity assessment (see figure). This approach is primarily used in limestone reservoirs, such as the Khuff, Arab, Habshan, Lekhwair, Kharaib, Shu’iaba, Natih and Misrif formations, where the integration of these techniques helps to accurately determine a borehole's position within the reservoir. Continuous analysis during drilling provides real-time data, enabling informed decision-making that can lead to successful well delivery with improved production rates or increased storage capacity.

Advantages of using Viridien’s real-time rock data analysis for well placement

These analytical techniques provide critical insights for maintaining or repositioning the borehole within the reservoir, offering several advantages:

• Accurate wellbore placement using biosteering, which, when combined with lithofacies and porosity data, is crucial for optimal reservoir targeting, especially when Logging While Drilling (LWD) is unavailable.
• Cost-effective solution for gas and carbon storage drilling.
• Real-time updates of the field’s static reservoir model while drilling.
• Fault identification with biosteering, including vertical displacements, allowing precise steering back to the target horizon.

Viridien's legacy in the Middle East

Viridien, formerly CGG, operating from its Abu Dhabi Geoscience hub, has undertaken biosteering, rock-typing and porosity evaluation in the region since 1994. These techniques have been applied to develop fields including the Shu’aiba, Kharaib, Lekhwair and Habshan and Khuff reservoirs. In 2003, Viridien participated in the first UBCTD project in the UAE and biosteering was key to successful well delivery. Viridien has undertaken UBCTD projects in Saudi Arabia since 2009, supported by its state-of-the-art laboratories in the UK. The adoption of these specialist geological techniques has become more widespread in the UAE recently, where Viridien is providing expert well placement services for several clients. The future of wellsite geological services for field development is bright, and the Middle East is leading the way.

Learn more about Viridien integrated solutions for exploration and reservoir development drilling including wellsite biostratigraphy and other advanced techniques at:

Viridien: Wellsite Services (https://www.viridiengroup.com/expertise/geological-services/wellsite-services)