Incommensurate Global Cold-Seep Area Constructions and Their Consequences for an Iron-Bound Organic-Carbon Stock
Year: 2026
Type: preprint
Abstract: Global biogeochemical inventories require a spatial domain that is commensurate with the measured concentration, sediment mass, and ecosystem state. We re-evaluate the area term used by Ye et al. (2026) to estimate 142–218 Tg C of iron-bound organic carbon (Fe-OC) in the upper 30 cm of mature cold-seep sediment. Two primary results emerge. First, Ye et al. state that cold seeps occupy less than 0.05% of continental-slope area, citing a source that gives approximately 41 million km2 of slope. That statement implies less than 2.05 × 104 km2, yet the same article later applies 2.05–3.15 × 105 km2 without a domain conversion. Second, the two values in that reported span are not shown to be bounds from a common estimator. The identifiable lower-source premises form a top-down slope-area– occupation calculation; the upper numerical fingerprint is a bottom-up extrapolation of an approximately 350-km2 Haima field descriptor across a discovery-limited count of more than 900 seeps. The methods, spatial objects, sampling frames, and error structures are incommensurate, and “more than 900” cannot generate an upper bound at a nominal count of 900. Independent fluid-expulsion compilations and regional acoustic surveys document substantial inventory incompleteness and heterogeneity but do not supply a global activesediment area. The absolute stock also contains an undisclosed sediment-mass coefficient: reproducing both endpoints with the reported depth and Fe-OC content requires an effective value near 1.65 g cm−3. Interpreted as dry bulk density, this value is high relative to available regional and near-surface seep analogs, although not physically impossible. Replacing only 205,000 by the printed-premise product of 20,500 km2 still changes the corresponding endpoint from about 142 to 14.2 Tg C, but this is a controlled sensitivity, not a new lower bound. The disclosed record therefore does not support interpreting the published area pair or derived stock span as empirical global intervals.
DOI: 10.31223/x54n6g
Author: Luigi Caputi
Language: English
Subfield: Environmental Chemistry
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: green
OpenAlex ID: W7213532390