Tufas-carbonates that form in ambient-temperature, freshwater settings-are valuable paleoenvironmental proxies of their depositional conditions. In this study, we use tufa deposits from the Santa Cruz, CA region to (i) model regional paleohydroclimate and (ii) investigate controls of biosignature formation at multiple spatial scales. Previously undescribed inactive, spring-associated tufa mounds (~2 m wide and each over 1 m thick) from Henry Cowell State Park and Pogonip Park were investigated in this study. Henry Cowell additionally hosts carpeted, fluvial tufa adjacent to an active tufa-depositing spring. Infrared stimulated luminescence (IRSL) dating was used on cores collected from the two inactive mounds to determine the timing of carbonate growth. Radiocarbon ( 14 C) dating was carried out on charcoal fragments from the fluvial carbonates at Henry Cowell State Park. IRSL and 14 C dates of samples collected from the List of Appendices Appendix A: Distribution of ages for 'dark core' P1 .