Hawaii–Aleutian Time Zone Polynesia uses UTC−10 for its major cities. The Cook Islands also use the same time. These areas do not use DST. "Hawaii–Aleutian Time Zone" is a U.S. term and for that reason the Polynesian areas are not considered to be a part of the Hawaii–Aleutian Time Zone. Hawaii–Aleutian Time Zone The Hawaii–Aleutian Time Zone observes Hawaii–Aleutian Standard Time (HST), by subtracting ten hours from Coordinated Universal Time (). The clock time in this zone is based on the mean solar time of the 150th meridian west of the Greenwich Observatory. The zone takes its name from the two areas it
Aleutian subduction zone Aleutian subduction zone The Aleutian subduction zone is a ~2500 mile-long convergence boundary between the North American Plate and the Pacific Plate, that extends from the Alaska Range to the Kamchatka Peninsula. Here, the Pacific Plate is being subducted underneath the North American plate and the rate of subduction changes from west to east from 7.5 cm/yr to 5.1 cm/yr. The Aleutian subduction zone includes two prominent features, the Aleutian arc and the Aleutian trench. The island arc was created via volcanic eruptions from dehydration of the subducting slab at ~100 km depth. The trench is a narrow and deep