Philippine Standard Time Philippine Standard Time Philippine Standard Time (, abbreviated PST or PhST), also known as Philippine Time (PHT), is the official name for the time in the Philippines. The country only uses one time zone (), and for a short period, it also used daylight saving time. Geographically, the Philippines lies within 116°40′ and 126°34′ east of the Prime Meridian, and is physically located within the time zone. Philippine Standard Time is maintained by the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). The Philippines shares the same time zone with Hong Kong, Macau, Singapore, China, Taiwan, Malaysia, Brunei, central Indonesia,
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