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 andesite, while the middle crust is composed of 5 km-thick mid-ocean ridge basalt (MORB), and 19 km- thick tholeiitic residue in the lower crust. Continental crusts usually have silicic upper crust and reflective lower crust, but these features are not found in the Aleutian arc. There are 40 active volcanoes in the Aleutian volcanic arc from the Mt. Spurr in mainland Alaska to Buldir Island in the far west Aleutian islands. The list of volcanoes in the Aleutian Arc could be found here. The eastern end of the volcanic arc on the Alaska Peninsula lies on Mesozoic sedimentary and volcanic