Knowledge Base Question

Why is there a time difference in reporting earthquakes?

IRIS Webmaster gravatar

IRIS Webmaster  staff  Nov. 14, 2013, 4:03 p.m.

I have been reading your charts for some time, but know I have come to ask you a question of where our activity may have come from.

I am living in Honiara, Solomon Islands. We often feel tremors, but last night we had one at approximately 9 to 10.30 pm. Yet your charts indicates one activity for this area at 10.30 in the morning.

Does it take this many hours to reach us from the bottom of the sea or did this tremor come from another area?

taber gravatar

taber  accepted answer  user  Nov. 14, 2013, 4:04 p.m.

The waves from a nearby earthquake will only take seconds to minutes to reach you. Some waves do take hours to travel around the earth but those are too small to feel.

What you might not know is that the times listed on our website are in Universal Time (UTC), which is the time in Greenwich, England. Your local time is 11 hours ahead of that time (see your location on Time and or an explanation of UTC ) which I think might explain the time difference you mention.