High Resolution Reservoir Monitoring using Crosswell Seismic

Abstract

Crosswell seismic is an emerging technology which provides highly detailed images of the subsurface at the reservoir scale. The technology has the potential not only to delineate complex structure but also to monitor the effectiveness of hydrocarbon recovery and CO2 sequestration strategies.The technique employs tomographic surveying, whereby a transmitter and receiver are deployed in separate wells. With this setup, interwell velocity profiling and structure can be obtained from direct wave and reflection processing respectively. With hydrocarbon recovery and CO2 sequestration becoming more prominent in the oil and gas industry, the ability to monitor the efficiency of these strategies is paramount. In this paper, two case studies of crosswell seismic surveying are discussed with the focus on high resolution imaging and monitoring during CO2 injection for improved oil recovery and sequestration respectively. A brief description of the measurement theory and its capabilities is provided, followed by a description of the processing workflow and finally a discussion of the acquired results. These two cases discussed demonstrate that crosswell seismic was able to successfully monitor the injection through velocity profiling in time lapse and provide answers as to why and how the flow has occurred through interpretation of the crosswell reflection seismic section. The results clearly show that crosswell seismic could significantly reduce the uncertainty and risk associated with injection processes for both improved recovery and sequestration.

Exploring the Impacts of Source Condition Uncertainties on Far‐Field Brine Leakage Plume Predictions in Geologic Storage of CO2: Integrating Intermediate‐Scale Laboratory Testing With Numerical Modeling

“…Therefore, the homogeneity assumption for the storage formation should only be considered when the layer underling the damage zone is homogeneous, and the equivalent K is representative for this layer. Therefore, it is important to first identify the potential leakage pathways in the Caprock (Ingram & Urai, 1999; Ligtenberg, 2005) and then characterize the local heterogeneity underling them with high‐resolution methods, such as cross‐well seismic imaging (Nalonnil & Marion, 2012; Yu et al., 2008).…”

Controlling potential far‐field brine leakage from CO2 storage formations using deep extraction wells: Numerical and experimental testing

“…These findings suggest that the extraction well locations can be determined prior to CO 2 injection using high‐resolution data on storage zone heterogeneity collected during site investigation. Such high‐resolution data can be obtained by applying techniques like cross‐well seismic imaging between the injection and monitoring wells before operation 114,115 . However, the extraction rates can be initially estimated using the available data prior to CO 2 injection, but such rates would need to be revisited and adjusted based on the leakage pathways’ permeabilities.…”

“…Such high-resolution data can be obtained by applying techniques like cross-well seismic imaging between the injection and monitoring wells before operation. 114,115 However, the extraction rates can be initially estimated using the available data prior to CO 2 injection, but such rates would need to be revisited and adjusted based on the leakage pathways' permeabilities. Such permeabilities can be inferred using transient monitoring data on the pressure changes and plume development in the system that become available after GCS operation and leakage onset.…”