We have developed a portable active seismic source (PASS) to monitor CO₂ storage reservoirs at a depth of approximately 1 km. Despite its small size, stacking the signals generated by the PASS improves the signal-to-noise ratio of the seismometer data far from the source. The smaller size and lower cost of the PASS enables its permanent deployment in many locations to continuously monitor CO₂ storage reservoirs. To achieve continuous monitoring, distributed acoustic sensing (DAS) is also a vital technology. Based on DAS, we can continuously record the signal from the PASS in an extensive area, including within boreholes and offshore fields. Here we report application of the PASS for the borehole DAS system. We confirmed the PASS signal propagation to a depth of ∼1 km when we used a PASS with 630N at 50 Hz close to the wellhead and recorded the signal by the borehole fiber optic cable. The ability of the system to propagate the PASS signal to a depth of ∼1 km enables continuous monitoring of most CO₂ storage reservoirs with high temporal resolution. Furthermore, deploying multiple PASS systems could improve the spatial resolution of monitoring results. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

中文翻译：

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信号从便携式主动震源 (PASS) 传播到公里级钻孔 DAS，用于连续监测 CO2 储存场地

我们开发了便携式主动地震源（PASS）来监测约1公里深度的CO ₂储存库。尽管尺寸很小，但叠加 PASS 生成的信号可以提高远离源头的地震仪数据的信噪比。 PASS 尺寸更小、成本更低，使其能够在许多地点永久部署，以持续监测 CO ₂储存库。为了实现连续监测，分布式声学传感（DAS）也是一项至关重要的技术。基于 DAS，我们可以在广阔的区域（包括钻孔内和海上油田）连续记录来自 PASS 的信号。在此，我们报告 PASS 在钻孔 DAS 系统中的应用。当我们在井口附近使用 630N、50 Hz 的 PASS 并通过钻孔光缆记录信号时，我们确认了 PASS 信号传播到~1 km 的深度。该系统能够将 PASS 信号传播到~1 km 的深度，从而能够以高时间分辨率连续监测大多数 CO ₂储存库。此外，部署多个 PASS 系统可以提高监测结果的空间分辨率。 © 2023 化学工业协会和 John Wiley & Sons, Ltd.