Mount Garibaldi - Geology

Geology

Mount Garibaldi lies within the Coast Plutonic Complex, which is the single largest contiguous granite outcropping in North America. The intrusive and metamorphic rocks extend approximately 1,800 km (1,118 mi) along the coast of British Columbia, the Alaska Panhandle and southwestern Yukon. This is a remnant of a once vast volcanic arc called the Coast Range Arc that formed as a result of subduction of the Farallon and Kula Plates during the Jurassic-to-Eocene periods. In contrast, Garibaldi, Meager, Cayley and Silverthrone areas are of recent volcanic origin.

Mount Garibaldi is one of the few Cascade volcanoes that is made exclusively of dacite (Glacier Peak is the other). The mountain has a unique asymmetrical shape because its main cone was constructed atop part of a large glacier system associated with the Cordilleran Ice Sheet that has since melted away. Unlike many of the other Cascade volcanoes to the south, Garibaldi does not dominate the surrounding landscape, which consists of many high, rugged peaks. Many residents of Vancouver are therefore not aware that there is a volcano closer to the city than the more easily visible Mount Baker in Washington State.

Read more about this topic:  Mount Garibaldi