With special permission, qualified geologists interested in volcanic processes and hydrothermal systems have been allowed to conduct research on the preserve. One of those volcanologists, Fraser Goff, collaborated with the Valles Caldera Trust to provide an accessible scientific overview of the caldera's geologic wonders. Presented in two parts, Valles Caldera first offers a summary of significant geologic events that have taken place in the Valles Caldera area. Then Goff presents the geology, volcanology, and geothermal characteristics of the Caldera and the Jemez volcanic field. Geologic terms and names unfamiliar to all but professional geologists are defined in a summarizing glossary.