Rare earth element geochemistry in cold-seep pore waters of Hydrate Ridge, northeast Pacific Ocean

Authigenic carbonates related to active seepage of methane-rich hot brines at the Cheops mud volcano, Menes caldera (Nile deep-sea fan, eastern Mediterranean Sea)

“…Alternatively, the slight enrichment of heavy REEs observed in the concretions recovered in bottom sediments of the brine lake could indicate that they precipitated from an alkaline-rich fluid source, possibly the CO2-rich fluid discussed above. Indeed, recent work has suggested that total alkalinity levels in pore waters could influence the distribution of REEs in cold seep carbonates (Rongemaille et al 2011;Himmler et al 2013), with highly alkaline fluids favouring precipitation of authigenic carbonates characterized by heavy REE enrichments.…”

Impact of anaerobic oxidation of methane on the geochemical cycle of redox-sensitive elements at cold-seep sites of the northern South China Sea

“…The influence of seeping fluids and AOM on marine trace-element chemistry is also not clear. Recently, very limited rare earth element (REE) studies on pore water aim at the impact of cold seeping fluids on REE biogeochemistry (Bayon et al, 2011;Himmler et al, 2013). Similarly, to our best knowledge, there has been no comparable work for trace redox-sensitive elements (e.g.…”

For the deep biosphere, the present is not always the key to the past: what we can learn from the geological record

“…A range of different chemical and isotopic signatures can be used as diagenetic proxies. Trace elements are commonly used as indicators of redox conditions near the sediment–water interface (Tribovillard et al ., ; Himmler et al ., ). Oxygen isotopes are indicative of temperature but also, in some cases, of the origin of the pore fluid (e.g.…”