What conditions in water columns and sediments are most favorable for the formation of pyrite (iron disulfide)?

How are trace metals incorporated into sulfide minerals in environments with variable oxygen concentrations?

How do complex sulfur redox intermediates affect sulfide mineral formation and the sulfurization of organic matter?

How do disruptions to the global cycling of gypsum (calcium sulfate) affect seawater pH and alkalinity over million-year timescales and beyond?

How might these shifts change how we interpret proxies for ancient carbon dioxide concentrations?