Conversion of Time

Conversion of GMT to Local Time

The date and time of earthquake occurrence is expressed in either local time [e.g., Mountain Standard Time (MST), Mountain Daylight Time (MDT)] or in Greenwich Mean Time (GMT). GMT time (sometimes referred to as Coordinated Universal Time or UTC) is the time along the prime meridian through Greenwich, England, and is used as a time standard throughout the world. Local time (MST) is 7 hours behind GMT (i.e., local time = GMT – 7 hours). [During three time periods, GMT was 6 hours earlier than MST (02:00 Mar. 30, 1918 to 02:00 Oct. 27, 1918; 02:00 Mar. 30, 1919 to 02:00 Oct. 26, 1919; and 02:00 Feb. 9, 1942 to 02:00 Sept. 30, 1945)]. Seismologists routinely convert from local time to GMT for research purposes to avoid potential problems in translating between time zones around the world.

MST

GMT

MDT

12 (midnight) 07 01 (1 am)
01 (1 am) 08 02
02 09 03
03 10 04
04 11 05
05 12 06 (6 am)
06 (6 am) 13 07
07 14 08
08 15 09
09 16 10
10 17 11
11 18 12 (noon)
12 (noon) 19 01 (1 pm)
01 (1 pm) 20 02
02 21 03
03 22 04
04 23 05
05 00 06 (6 pm)
06 (6 pm) 01 07
07 02 08
08 03 09
09 04 10
10 05 11
11 06 12 (midnight)