A paper by Assistant Prof. Tatsunori Ikeda, Prof. Takeshi Tsuji (CO2 Storage Division, I2CNER) and their collaborative research group has been published in "Journal of Geophysical Research: Solid Earth".
In this study, we continuously monitored temporal variation of seismic velocity at the Aquistore CO2 storage site using a controlled seismic source system (Figure 1). As a result, we revealed seasonal variation of seismic velocity associated with the degree of freezing in shallow sediments. Our results contribute to reliable monitoring of CO2 storage sites because shallow seismic velocity variation affects monitoring accuracy of deep CO2 injection reservoirs. The high temporal stability of our monitoring approach has a potential to identify CO2 leakage. This effort directly addresses the mid-term milestone of Project 3 of the CO2 Storage Division (Field-scale CO2 investigation).
Title：Temporal variation of the shallow subsurface at the Aquistore CO2 storage site associated with environmental influences using a continuous and controlled seismic source
Authors：Tatsunori Ikeda, Takeshi Tsuji, Mamoru Takanashi, Isao Kurosawa, Masashi Nakatsukasa, Ayato Kato, Kyle Worth, Don White, Brian Roberts
(Left) Aquistore CO2 storage site in Canada (http://rmc.usc.edu/assets/002/96013.pdf)
(Right) Controlled seismic source system used in this study