11:15 AM - 11:30 AM
[HSC07-09] Experimental demonstration of wireline DAS-VSP for cost-effective CCS monitoring in a coastal area CCS
Keywords:CCS monitoring, DAS-VSP, Coastal area CCS
The active seismic method is widely used in CCS monitoring to understand the behavior of CO2 plumes. Although technical effectiveness has been proven in many projects, cost reduction is a major issue. It is crucial for coastal area CCS as seismic acquisition is generally complicated in those areas. In addition, seismic acquisition around coastal areas has an impact on fishing activities and that should be minimized for a long-term CCS project.
DAS-VSP is one of the possible cost-effective solutions as they can be deployed in a well easily or permanently. For coastal areas, DAS-VSP can eliminate OBCs or OBNs and this has a large effect on a monitoring cost and an impact on fishing activities. In addition to coastal areas, one of the current storage targets is injection into existing depleted gas fields. In this situation, it will be more cost-effective if existing wells can be used.
Although many case studies of DAS acquisition have already been reported, various factors could affect the quality of DAS (Willis, 2022). The wireline or slickline deployment method in particular is affected by individual circumstances, such as well conditions. Therefore, it is important to gather case studies to understand the performance of DAS toward large-scale CCS.
We conducted 2D and 3D DAS-VSP experiments in 2022 and 2023 to acquire basic knowledge of factors affecting its quality. We first used a shallow experimental well and found that the quality is affected by well conditions. After the first experiment, we acquired 2D and 3D DAS-VSP data using existing old wells in our oil field. Several test datasets were acquired in those experiments. We present and share some of our current findings and discuss a possible monitoring plan for coastline CCS.
Reference
Willis, M. E. (2022): Distributed Acoustic Sensing for Seismic Measurements – What Geophysicists and Engineers Need to Know, SEG Distinguished Instructor Short Course.
DAS-VSP is one of the possible cost-effective solutions as they can be deployed in a well easily or permanently. For coastal areas, DAS-VSP can eliminate OBCs or OBNs and this has a large effect on a monitoring cost and an impact on fishing activities. In addition to coastal areas, one of the current storage targets is injection into existing depleted gas fields. In this situation, it will be more cost-effective if existing wells can be used.
Although many case studies of DAS acquisition have already been reported, various factors could affect the quality of DAS (Willis, 2022). The wireline or slickline deployment method in particular is affected by individual circumstances, such as well conditions. Therefore, it is important to gather case studies to understand the performance of DAS toward large-scale CCS.
We conducted 2D and 3D DAS-VSP experiments in 2022 and 2023 to acquire basic knowledge of factors affecting its quality. We first used a shallow experimental well and found that the quality is affected by well conditions. After the first experiment, we acquired 2D and 3D DAS-VSP data using existing old wells in our oil field. Several test datasets were acquired in those experiments. We present and share some of our current findings and discuss a possible monitoring plan for coastline CCS.
Reference
Willis, M. E. (2022): Distributed Acoustic Sensing for Seismic Measurements – What Geophysicists and Engineers Need to Know, SEG Distinguished Instructor Short Course.