Multibeam bathymetry and backscatter data collected during SMARTEX cruises JC241 and JC257 in the Clarion-Clipperton Zone

Multibeam bathymetry data were collected in the Clarion-Clipperton Zone (CCZ), Northeast Pacific Ocean, using a hull-mounted Kongsberg EM122 multibeam echosounder during RRS James Cook Cruise JC241 from 06/02/2023 to 25/03/2023, and JC257 from 08/02/2024 to 19/03/2024. Data acquisition began upon exiting the Costa Rican Econoic Exclusion Zone (EEZ), suspended within the Clipperton Island EEZ, and resumed upon exiting the Clipperton Island EEZ. Data were then acquired throughout the CCZ. This suspension was repeated on the return journey. The data were recorded using Kongsberg’s Seafloor Information System (SIS) in .all format, and CTD and model-derived sound velocity profiles were subsequently applied. The data were manually cleaned using swath and subset editors in CARIS HIPS and SIPS software version 10.4. A zero tide file was also applied. The data were collected to obtain a better insight in the biodiversity patterns and benthic habitat distributions within the CCZ, by scientists from the National Oceanography Centre, Southampton, UK as part of the NERC-funded Seabed Mining And Resilience To EXperimental impact (SMARTEX) project (NE/T003537/1).