Volcanology: Volcanology is a branch of geology that focuses on the study of volcanos. In volcanology, geologists conduct field and laboratory investigations to learn about continental, coastal, and submarine volcanic activities. In fact, volcanology ties into many other branches of geology. For instance, a volcanologist may study the geochemistry of igneous rocks, such as extrusive volcanic rocks, and other intrusive plutonic rocks. Similarly, volcanology can overlap with seismology and tectonic geology, in the sense that volcanologists study earthquakes and subduction zone plate tectonic boundaries. There are numerous other applications of geology that apply in volcanolgoy.