The textures, major and trace element geochemistry and nitrogen concentrations and isotopic compositions of Antarctic, Iceland and Oregon subglacial and lacustrine hyaloclastites, and 44 samples of terrestrial potassic and micro- and meso-porous, mainly basalt alteration Mars-analog minerals, were studied to understand how N could be incorporated and stored during weathering and low temperature hydrothermal alteration in Mars surface/near-surface environments. Most samples contain more N than fresh MORBs or OIBs reflecting enrichment beyond concentrations attributable to igneous processes and have δ15N consistent with the incorporation of biologically processed N in low-temperature hydrothermal or weathering environments. Antarctic samples contain 52-1143 ppm N and have δ15Nair values of -20.8‰ to -7.1‰ whereas Iceland-Oregon basalts contain 1.6-172 ppm N with δ15N of -6.7‰ to +7.3‰. Phyllosilicates, zeolites, and sulfates contain 0 to 99121 ppm N and have δ15N values of -34.0 to +65.4‰. For altered hyaloclastites, the incorporation of N as NH4 + is indicated by correlations of N concentrations and the LILEs (e.g., K, Rb, Cs) with scatter likely related to exchanged, occluded/trapped, or encapsulated organic/inorganic N within structural cavities (e.g., in zeolites). Secondary ion mass spectrometry mapping confirms N residency in smectites, zeolites, and silica. Geological materials known on Earth to incorporate and store N and to be abundant at/near the Mars surface should be considered targets for upcoming Mars sample return aimed at identifying textural or chemical signs of ancient or modern life.

High temperature submarine hydrothermal venting from black smokers along mid ocean ridges is a major source of chemical species to the oceans. We present a major and trace element and dissolved gas dataset measured in fluids collected from 23 distinct hydrothermal vents on the southern East Pacific Rise in November 1998 extending southward from 17°26' to 17°37', 17°44', 18°25', 21°26', and 21°34'S. A calibrated Fe/Mn geothermometer with constraints imposed by dissolved Si-Cl indicate minimum subseafloor equilibration temperatures and pressures of 374-438°C and 290-418 bar and cooling during ascent. Chloride concentrations indicate two-phase behavior is a prominent controlling process on compositions, but tectonic versus magmatic drivers, HM or AACMP mineral buffers, and ridge host rock compositions also control endmember compositions.