Sulfur in Hydrothermal Fluids

TL;DR

This chapter reviews sulfur chemistry in hydrothermal fluids across various geological settings, highlighting recent analytical advances and their implications for metal transport and ore deposit formation.

Contribution

It provides a comprehensive overview of sulfur speciation, emphasizing in situ methods and their impact on understanding hydrothermal metal transport.

Findings

In situ approaches have advanced sulfur chemistry insights.

Sulfur ligands influence metal transport in hydrothermal systems.

The role of sulfur in ore deposit formation is critically evaluated.

Abstract

This chapter overviews sulfur chemical speciation and behavior in different types of hydrothermal fluids across the lithosphere, spanning from active geothermal systems to basinal brines, to metamorphic and magmatic-hydrothermal fluids. The information on sulfur in these fluids stems from a wide range of recent analytical, experimental and computational methods whose advantages and limitations are discussed. A special emphasis is given to in situ approaches that have enabled unprecedented insights into the fascinating sulfur chemistry in hydrothermal fluids. These insights motivated a critical review of the chemical speciation of key base, precious, and critical metals whose behavior is intimately linked to sulfur. The results allow the role played by the different sulfur ligands on hydrothermal transport of metals and ore deposit formation to be evaluated. An outline of major challenges and emerging perspectives for sulfur-related research in geological fluids ends up this chapter.