This is version 4.0 of MARHYS (MARine HYdrothermal Solutions) database. The database is a global compilation of marine hydrothermal vent fluid compositions. The database includes data presented in journal publications, book chapters and monographs and includes compositions of hydrothermal fluids, end members and background seawater. Detailed sample information (metadata) is provided along with the chemical composition, which enables the unique identification of discrete vent fluid samples. The database contains concentrations of major-, minor- and trace elements, as well as, reduced carbon compounds and isotope compositions. All concentrations are converted into units per kg of vent fluid and chemical data of unique samples reported in different publications are merged into unique sample entries.
In brief, the following changes have been applied in the course of the compilation of MARHYS database version 4.0 compared to version 3.0: Two new classes of geological settings have been established: "Intra-plate volcano" with Kamaʻehuakanaloa (Lōʻihi) and Teahitia Vents as representatives and "Ridge flank" with Baby Bare and ODP 1026 as representatives. Data of 66 new references have been added to the database. Some new vent sites are now incorporated: Jøtul Field, Kamaʻehuakanaloa (Lōʻihi), Nakayama Vent Field, Old City Hydrothermal Field, Saldanha Hydrothermal Field, Teahitia Vents. The size of the database has grown compared to Version 4.0 and now contains 6788 merged sample entries compared to 6003 merged entries in Version 3.0. The sample information section has been overhauled for more consistency in the location description. Some new parameters are now included in the database: Eh, TDN (Total Dissolved Nitrogen), Hg, SPE DOC and a number of isotope ratios. Again, existing data was scanned for erroneous entries and corrected wherever found. The reference list was updated and the reference list is now presented in "APA7th" style to contain hyperlinks to the references for more comfortable use.
