Critical Review of the Article: "Evidence of Dark Oxygen Production at the Abyssal Seafloor" by Sweetman et al. in Nat. Geosci. 1–3 (2024)

This review examines the findings and methodologies presented in Sweetman et al. (2024) (hereafter referred to as ‘the paper’). The paper presents findings contrasting those of all previous comparable work and has stirred international debate pertaining to deep-sea minerals. We identify significant issues in data collection, validation, and interpretation including unvalidated data collection methods, the omission of crucial observations relevant for electrolysis processes, and unsupported voltage measurements which undermine the study's conclusions. These issues, coupled with unfounded hypotheses about early Earth oxygen production, call into question the authors’ interpretation of the observations and warrant re-examining the validity of this work. Our analysis is driven by scientific curiosity of mineral related processes, as our company has no vested interests in nodule production.