Stern, Robert J.2020-08-272020-08-272020-052020-05May 2020https://hdl.handle.net/10735.1/8831This study is a multidisciplinary data integration and metadata analysis for mid-ocean ridge (MOR) and Mariana intra oceanic convergent margin hydrothermal vents including fluids and biota. We compiled separate databases for MOR and Mariana hydrothermal vent parameters and their vent biota using published and on-line information managed by government agencies and other research institutes. The vent parameter databases are compiled under the categories of setting, vent field name, vent field number, name, latitude, longitude, alias, vent sites, smoker type and chimney composition, host rocks, full spreading rate, depth, temperature, pH, total Fe, (³He/⁴He)/Rₐ, CO₂, CH₄, H₂, H₂S, SO₄²⁻ ions, chlorinity, operations and references. MOR database for vent parameters includes 449 individual hydrothermal vents grouped into 73 vent fields at global divergent margins. The vent organism database of MOR vents includes 672 species belong to 72 individual vents. Mariana vent summary database includes 47 individual hydrothermal vents belong to four different tectonic settings: the forearc (FAR), arc (ARC), backarc (BAB) and the southern Mariana trough (SMT). Database for Mariana biota include vent animals for 31 vents of the above settings. We considered vent depth, fluid temperature, pH, total Fe, Mn, helium isotopic ratio ((³He/⁴He)/Rₐ), fluid gases (CO₂,CH₄, H₂, H₂S), SO₄²⁻ ions and chlorinity of the fluids for statistical analysis. In addition to these parameters, for MOR vents full spreading rate was also considered for statistical analysis. To overcome non-linear data distributions and small number of observations for some vent parameters, we used purely nonparametric statistical procedures. We assessed vent fluid parameters first for correlations with key parameters spreading rate (for MOR only), summit depth, fluid temperature and fluid chlorinity. Second, we compared different segments (MOR segments and Mariana tectonic settings) based on vent parameters. Similarities between the vent organisms in different tectonic segments were assessed using Sörensen similarity indices; for MOR vents at both genera and species levels; and for Mariana only for genus level. Our results for MORs show that even if MOR hydrothermal systems are associated with simple divergent margin tectonism, they are remarkably similar despite having differences in both fluid chemistry and biota distribution regardless of the ocean and the rate of spreading. Vent fluid temperature, pH, Fe, Mn, CO₂, H₂, SO₄²⁻ ion and chlorinity are independent of the spreading rate. Fluid temperature does control pH, Fe and H₂S. Brine separation might influence gases such as helium isotopic ratio and CO₂ in venting fluids. Highest similarities of the macro organisms are seen in the Indian Ocean ridges and the greatest differences are observed in the Pacific Ocean ridges. Integration of tectonics, fluid chemistry and vent biota of Mariana convergent margin vents demonstrate that Mariana vent groups are more diverse than global mid-ocean ridge vents and that the southernmost Marianas most resembles mid-ocean ridge (MOR) type venting, the other tectonic groups are quite different than MOR vents.application/pdfen©2020 Diluni Ayeshika Wimalaratne Hetti Pathirannehelage. All rights reserved.Hydrothermal ventsOrganismsMid-ocean ridgesBack-arc basinsIsland arcsEast Pacific RiseMid-Atlantic RidgeGeology -- Indian OceanMariana TrenchThesis2020-08-27