CO2 was injected into shallow unconsolidated marine sediments in Ardmucknish Bay, Oban. 2D seismic reflection data were collected pre-release (15/05/2012), syn-release (17/05/2012, 18/05/2012, 19/052012, 29/05/2012, 30/05/2012, 20/06/2012) and after release stages (23/04/2014 and 24/04/2014) of CO2 help to better understand the spatial and temporal evolution of free gas anomalies within the overburden. The impact of CO2 on sediment acoustic properties, namely seismic reflectivity and attenuation, was also investigated. This dataset was collected by the National Oceanography Centre Southampton (NOCS) and the British Geological Survey (BGS) under the program QICS (Quantifying and monitoring environmental impacts of geological carbon storage) which was funded by the Natural Environment Research Council (NERC), with support from the Scottish Government. The dataset includes segy files, a presentation which summarises the main results and a map showing the spatial extent of the seismic data collected after gas release. QICS project website: http://www.bgs.ac.uk/qics/home.html. Cevatoglu et al., 2015. Gas migration pathways, controlling mechanisms and changes in sediment acoustic properties observed in a controlled sub-seabed CO2 release experiment. Int J Greenhouse Gas Control. DOI:10.1016/j.ijggc.2015.03.005. The post-release data is currently restricted. NERC grant NE/H013873/1
