Alaska Time Zone Alaska Time Zone The Alaska Time Zone observes standard time by subtracting nine hours from Coordinated Universal Time (). During daylight saving time its time offset is eight hours (). The clock time in this zone is based on mean solar time at the 135th meridian west of the Greenwich Observatory. The zone includes nearly all of the U.S. state of Alaska and is one hour behind the Pacific Time Zone. The western Aleutian Islands observe Hawaii–Aleutian Time, one hour behind the remainder of the state. Effective from 2007, the local time changes from AKST to AKDT at 02:00 LST
Aleutian subduction zone rocks, with trace amounts of Paleozoic rocks intruded by Mesozoic batholiths. Most of the Aleutian Islands are composed of sedimentary rocks from granitic and metamorphic rocks from Oligocene-Miocene. There are Quaternary volcanoes on the north of the Aleutian Islands structural axis, which is composed of andesite mostly, mixed with olivine basalt to rhyolite. The eastern Aleutian volcanoes have more silicic magma while the western Aleutian arcs lack the sial magma. The Aleutian Trench formation is associated with the subduction of the Pacific Plate beneath the North American plate. The horizontally-curved shape of the trench is due to the change in