[CEUS-earthquake-hazards] FW: Report on estimating maximum magnitude in the Central and Eastern US.

[Keifer, John D]

Ellis, it would still seem that everything depends on the criticality of the structure. How would you define criticality.  Also, while you are right that no one can tell you that a 10,000 year earthquake won't happen tomorrow, the longer the time span the lower the probability that it will happen tomorrow.

John

-----Original Message-----
From: ceus-earthquake-hazards-bounces at geohazards.usgs.gov [mailto:ceus-earthquake-hazards-bounces at geohazards.usgs.gov] On Behalf Of Krinitzsky, Ellis L ERDC-GSL-MS Emeritus
Sent: Tuesday, May 26, 2009 1:53 PM
To: Central and Eastern U.S. Earthquake Hazards Listserve
Subject: Re: [CEUS-earthquake-hazards] FW: Report on estimating maximum magnitude in the Central and Eastern US.

That is a wrong assumption. For a critical structure, protection must be
regardless of time. That is the essential quality of a deterministic
evaluation. 

-----Original Message-----
From: ceus-earthquake-hazards-bounces at geohazards.usgs.gov
[mailto:ceus-earthquake-hazards-bounces at geohazards.usgs.gov] On Behalf Of
Wang, Zhenming
Sent: Thursday, May 07, 2009 12:11 PM
To: Central and Eastern U.S. Earthquake Hazards Listserve
Subject: [CEUS-earthquake-hazards] FW: Report on estimating maximum magnitude
in the Central and Eastern US.

Time is a fundamental element that must be considered in any activity.


-----Original Message-----
From: Krinitzsky, Ellis L ERDC-GSL-MS Emeritus
[mailto:Ellis.L.Krinitzsky at usace.army.mil] 
Sent: Thursday, May 07, 2009 10:01 AM
To: Central and Eastern U.S. Earthquake Hazards Listserve
Cc: Wang, Zhenming
Subject: RE: [CEUS-earthquake-hazards] Report on estimating maximum magnitude
in the Central and Eastern US.

Everything depends on the criticality of the structure. If the structure is
critical (the consequences of failure are intolerable) then one must design
for the maximum earthquake regardless of temporality. Otherwise, it is proper
to design on a cost-risk basis.

Nobody can say that a 1,000-year earthquake or a 10,000-year, both based on
150-year record, will not happen tomorrow. The 10,000-year earthquake,
assuming the time estimate has any meaning, could just as well be more likely
to happen.

Ellis Krinitzsky
Corps of Engineers, ERDC, Vicksburg  

_______________________________________________
CEUS-Earthquake-Hazards mailing list
CEUS-Earthquake-Hazards at geohazards.usgs.gov
https://geohazards.usgs.gov/mailman/listinfo/ceus-earthquake-hazards
_______________________________________________
CEUS-Earthquake-Hazards mailing list
CEUS-Earthquake-Hazards at geohazards.usgs.gov
https://geohazards.usgs.gov/mailman/listinfo/ceus-earthquake-hazards