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Fiber-optic sensing and its utilization and capabilities are being maximized now more than ever within the energy industry. Unlike traditional measurements that rely on discrete sensors measuring at predetermined points, distributed sensing technology uses fiber-optic strands as the sensor, enabling continuous, real-time measurements captured along the entire length of a fiber-optic strand.
Optiq Schlumberger fiber-optic technologies cover distributed acoustic sensing (DAS), distributed temperature sensing, distributed temperature gradient sensing, and distributed strain and temperature sensing systems for a wide range of applications across energy industries, including oil and gas, carbon capture and storage, geothermal energy production, and mining.
These tools can be permanently installed with the completion string, behind casing, along pipelines or other infrastructure, or temporarily deployed via fiber-optic wireline, slickline or coiled tubing conveyances. The conveyance-agnostic Optiq tools provide unmatched operational flexibility, data assurance, integrated measurements and actionable insights throughout the project life cycle. Powered by end-to-end cloud-native workflows and backed by a century of domain expertise, Optiq technologies provide operators with consistent results and an improved user experience from planning, acquisition and processing to data consumption.
For reservoir applications, operators can acquire borehole seismic images, monitor production, stimulation and injection, evaluate well integrity and more using Optiq technologies. For oil and gas pipelines, the tools act as remote monitoring systems providing real-time distributed leak detection, pig tracking and integrity threat monitoring, such as perimeter intrusion and theft detection.
Optiq technologies enable operators to better understand their reservoirs, improve production and monitor asset integrity—all with reduced environmental impacts.
Fiber-optic borehole seismic
Traditional methods for acquiring borehole seismic data for reservoir characterization are often time-intensive and require a dedicated run that increases cost, carbon emissions and overall risk, especially in offshore environments. Schlumberger's Optiq Seismic fiber-optic borehole seismic technology addresses these challenges by leveraging DAS technology, digital workflows, cloud-native software and unique conveyances that reduce data acquisition time and carbon emissions by up to 99%. This enables operators to improve understanding of subsurface reservoir structures during exploration, appraisal and development for optimizing the field development plan and potentially reducing the number of required wells.
The Optiq Seismic tool can acquire zero-offset, walkway, 3D seismic, 4D reservoir monitoring and other vertical seismic profiles (VSPs) with up to a 1.5-m spatial resolution in minutes, compared with hours or days using traditional methods. It is the industry’s first end-to-end, conveyance agnostic solution that eliminates the need for a dedicated borehole seismic descent. The tool's optical interrogator unit at surface is also conveyance agnostic and can record the full well profile for each shot.
Schlumberger's ultrastrength Optiq TuffLINE torque-balanced fiber-optic wireline conveyance, with 18,000-lbf max. safe working load, acquires VSPs in any exploration environment, including deepwater operations. Additionally, the Optiq StreamLINE polymer-locked fiber-optic wireline conveyance enables VSPs to be acquired during any production services run—an industry first. For permanent fiber-optic solutions, data from multiple wells can be acquired simultaneously without any deferred production.
From early field trials to date, the Optiq Seismic fiber-optic borehole seismic technology has been used to acquire more than 70 VSPs in more than 15 countries. In the Gulf of Mexico, the tool recorded 3D VSPs in four wells while they were still in production, saving 88 days of acquisition time and 8,000 metric tons of CO2e emissions compared with the conventional geophone method that would have taken 100 days. Using the tool's advanced de-noising workflow, high-resolutions images were obtained and utilized to identify previously unrecognized reservoir compartmentalization without deferred production.
In Norway, an operator deployed the Optiq Seismic technology to efficiently obtain high-resolution images and improve understanding of reservoir structure. The operator was able to acquire a zero-offset VSP in less than 30 minutes during wireline fluids sampling. In deepwater West Africa, zero-offset and walkaway VSPs were acquired in minutes compared with hours or days of conventional geophone acquisition.
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