Effects of time zones on North American broadcasting Effects of time zones on North American broadcasting The scheduling of television programming in North America (namely the United States, Canada, and Mexico) must cope with different time zones. The United States (excluding territories) has six time zones (Hawaii–Aleutian, Alaska, Pacific, Mountain, Central and Eastern), with further variation in the observance of daylight saving time. Canada also has six time zones (Pacific, Mountain, Central, Eastern, Atlantic and Newfoundland). Mexico has four time zones (Pacific, Mountain, Central, and Eastern). This requires broadcast and pay television networks in each country to shift programs in time to show them in different regions. Canadian
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