This dataset contains the percentage coverage of different substrate types (live scleractinian corals, dead scleractinian framework, rubble, hard substrates and fine sediments) found at the Logachev cold-water coral carbonate mounds. Video transect data were collected using the remotely operated vehicle (ROV) Holland-1 during the Changing Oceans Expedition 2012 on RRS James Cook (Cruise JC073) from 2012-05-27 to 2012-06-06. Image frames were extracted from the ROV videos and the percentage coverage was measured in Adobe Photoshop software (van der Kaaden and De Clippele, 2021). Terrain variables (i.e. Depth, Slope, Rugosity, Bathymetric Positioning Index) and Particulate organic matter (POM) per image file were extracted using the ESRI ArcMap v10.1 software. This data was used by De Clippele et al. (2021) to calculate biomass and to estimate the carbon and nitrogen turnover capacity of the study area.