Fiber Optic based Borehole Multi Sensor & Source System for Characterization and Monitoring of Carbon Storage Sites

There is today an urgent need to develop highly efficient, cost-effective and transparent solutions to characterize and monitor CO2 injection and storage sites on a reservoir scale. This to satisfy the public, regulators and operators that CO2 can be stored safely in both near and long term. To understand the monitoring processes at all we need first to understand the injection sites used for the storage of the CO2 using the highest possible resolution imaging. Monitoring, conducted after the site characterization is completed, must apply multiple sensors with different measurement attributes to record the important effects from injection and storage of the CO2. This includes monitoring for leakage to the atmosphere through the formation and the well bores as well as intra-formation and inter-formation flows of the CO2. Borehole high-frequency active clamped vector seismic vibratory sources and large optical seismic 3C vector receiver arrays are together uniquely suited for the site characterization task which is the first task that must be done prior to any injection. During the injection and monitoring phase the following all optical sensors will be deployed using the Paulsson deployment system: Source, 3C vector seismic, distributed acoustic, temperature, pressure and strain sensors. In addition, the deployment system is designed to deploy ¼” Inconel tubes allowing fluid sampling from and injection to the reservoir. To acquire the important formation parameters for CO2 sites we will research, design, build and test components for an all optical sensor string that consists of sensors and sensor arrays that can operate in high temperatures, up to 320°C, and high pressures, up to 20,000 psi, boreholes filled with corrosive fluids. Optical sensors do not require electronics in the borehole – only the sensors are in the well connected to the surface via fiber. We will design and laboratory test these multiple sensors and sensor arrays for deployment into borehole environments typical for the CCUS, Oil & Gas, Gas storage and Geothermal markets. The optical sensors are immune to electromagnetic interference. We will explore and select from existing Seismic, Acoustic, Static & Dynamic Pressure, Temperature and Strain sensors. The sensors, sensor arrays and borehole seismic source system developed under this project will benefit the CCUS, Oil & Gas, Gas Storage and Geothermal markets. The strength of fiber sensing is that the optical fiber transducer can translate the fiber strain into a variable of interest. This includes seismic, acoustic, pressure, temperature and strain. In the UOG markets it is estimated that only 8% of the Original Oil In Place is recovered. By utilizing the sensors developed in this project and obtaining better imaging and data it will increase the recovery rates significantly for both conventional and UOG fields. In the Geothermal market the efficiency of the energy extraction process will be improved by better fracture and formation characterization providing for a better efficiency of the geothermal energy extraction process.