QICS Paper: Detection and impacts of leakage from sub-seafloor deep geological carbon dioxide storage

Fossil fuel power generation and other industrial emissions of carbon dioxide are a threat to global climate1, yet many economies will remain reliant on these technologies for several decades. Carbon dioxide capture and storage (CCS) in deep geological formations provides an effective option to remove these emissions from the climate system. In many regions storage reservoirs are located offshore, over a kilometre or more below societally important shelf seas6. Therefore, concerns about the possibility of leakage, and potential environmental impacts, along with economics, have contributed to delaying development of operational CCS. Here we investigate the detectability and environmental impact of leakage from a controlled sub-seabed release of CO2. We show that the biological impact and footprint of this small leak analogue (<1 tonne CO2 d-1) is confined to a few tens of metres. Migration of CO2 through the shallow seabed is influenced by near-surface sediment structure, and by dissolution and re-precipitation of calcium carbonate naturally present in sediments. Results reported here advance the understanding of environmental sensitivity to leakage and identify appropriate monitoring strategies for full-scale carbon storage operations. This is a publication in Nature Climate Change, Jerry Blackford et. al. doi:10.1038/nclimate2381

化石燃料发电及其他工业二氧化碳排放对全球气候构成威胁，然而，许多经济体在未来的数十年内仍将依赖这些技术。深部地质结构中的二氧化碳捕获与储存（CCS）技术为从气候系统中移除这些排放提供了有效途径。在许多地区，储存库位于离岸，深度超过一公里，位于社会重要的近海大陆架上。因此，关于泄漏的可能性及其潜在的环境影响，以及经济因素，共同导致了操作级CCS开发的延缓。在本研究中，我们探讨了从受控海底释放二氧化碳的泄漏的可检测性和环境影响。研究表明，这种小型泄漏模拟（<1吨CO2每天）的生物影响和足迹局限于数十米范围内。二氧化碳通过浅海海底的迁移受近表层沉积结构、以及沉积物中天然存在的碳酸钙的溶解和再沉淀的影响。本研究报告的成果推进了对泄漏环境敏感性的理解，并确定了适用于大规模碳储存操作适宜的监测策略。这是一篇发表在《自然气候变化》杂志上的论文，作者为Jerry Blackford等人，DOI:10.1038/nclimate2381。