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Submarine methane seepage can potentially be promoted by the dissociation of the marine hydrates surrounding the continental margins due to oceanic warming since the Last Glacial Maximum. This seepage could be archived by authigenic carbonates at seeping sites, but the time lag caused by heat transmission through the sediment column leads to an inconsistency between the ages of the carbonate and the period of bottom water warming. Here we present the records of the authigenic carbonate crust from drilling site D1 in the Mid‐Okinawa Trough. Uranium–thorium dating results show that the carbonate crust mainly grew downwards during 14–6 ka. Gas hydrates hosted in the relatively thin stability zone dissociated in a rapid response to bottom water warming and intensified the methane seepage. Our study better supports the hypothesis that a considerable amount of methane can be released from marine hydrates due to global climatic changes. Plain Language Summary: Methane hydrates are ice‐like crystalline compounds and often found in deep‐ocean marine sediments. Ocean warming in the past could have destabilized methane hydrates and led to a rapid discharge of free methane gas. Geological information on this methane escape could be preserved by carbonate rocks. To date, the hypothesis of the control of ocean warming on hydrate melting since the Last Glacial Maximum (19,000–26,000 years ago) has not been fully tested. To examine this hypothesis, we used the rock samples of seep‐carbonate retrieved by seafloor drilling in the Mid‐Okinawa Trough. Uranium–thorium dating results show that the seep carbonates formed between 6,000 and 14,000 years ago. It took less time for heat to diffuse downwards from warming seawater to trigger hydrate melting at this location than in most of other oceans at similar water depths. The smaller time lag makes the carbonate rock age close to the period of ocean warming. Our results better support that global ocean warming could potentially release methane from gas hydrates during glacial–interglacial transitions. The consequent methane transport into the oceans and likely also the atmosphere might impact ocean acidification and climatic warming. Key Points: Presentation of the chronology of methane seepage by dating authigenic carbonates collected from drilling core D1 in the Okinawa TroughOcean warming–induced hydrate dissociation led to the downward growth of authigenic carbonate for 14–6 ka after the Last Glacial MaximumThis carbonate record better supports the link of hydrate dissociation with ocean warming due to a smaller thermal lag effect [ABSTRACT FROM AUTHOR]

• Pore water data show a strong AOM process at site ESC-15-08. • Biogenic methane is the primary carbon source of authigenic carbonates. • Remarkably positive δ18O values of seep carbonates reflects the fluid origin. • Pore water and authigenic carbonates are effective sources of information on fluid dynamics in cold seeps. The formation of authigenic carbonates at cold seep is closely related to underlying methane seepage and anaerobic oxidation of methane (AOM), and these processes can be reflected in the geochemical characteristics of pore water in the sediments. In terms of petrological, mineralogical and geochemical analyses of research materials, including authigenic carbonates and pore water samples from the middle Okinawa Trough, East China Sea,these results show that authigenic carbonate minerals are mainly composed of high-magnesium calcite, low-magnesium calcite, dolomite, and iron dolomite and exhibit extremely negative carbon isotopic compositions (δ13C = −52.30‰ to −31.10‰ V-PDB) and positive oxygen isotopic compositions (δ18O = 3.36‰ to 7.27‰ V-PDB). Geochemical analyses of pore water suggest linear sulfate gradients and steep increase of methane and total alkalinity concentrations with depth, which indicate sulfate-induced AOM activities. Based on the sulfate concentration reduction, carbon isotope characteristics of dissolved inorganic carbon (DIC) and increased methane concentration, the sulfate-methane interface (SMI) is considered to be shallow. These data, combined with the variations in ion concentrations in pore water, suggest that the leakage of biogenic methane and intense AOM resulted in the formation of abundant authigenic carbonates, which inherited light carbon (12C)-enriched isotopic signature of methane in the shallow sediments. Combined geochemical characteristics of pore water and authigenic carbonates, intense methane seep activities and associated AOM can be inferred both in present-day and ancient geological records on the western slope of the middle Okinawa Trough. [ABSTRACT FROM AUTHOR]