The e-mail is: chchquake@state.gov
If you are an American citizen with an emergency situation, you can also call:
+[64] (9) 303 2724 ext: 2900 (during normal business hours)
+[64] (4) 462 6000 (after normal business hours). You will be required to leave a message and the in-charge Duty Officer will return your call. Be sure to leave specific instructions (including your name, location and your phone number as well as any medical or travel information that may assist in your evacuation).