How to integrate between interfaces?

[Yang Kun <yangk@xxxxxxxxxxxxxx>]

Dear Ferreters,

I have a 3-d variable u(x,y,z), which has 11 layers with fixed 
depth. And I have another two 2-d fields with the same
x-y axis containing the depth of two interface, say,
z1(x,y),z2(x,y). Is there anyway I can integrate u between 
interface z1 & z2?

Thanks.

-Kun

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Kun Yang,   Researching Assistant
Dept. of Oceanography, Texas A&M Uni. College Station
Mailing Addr:  309, Ball Street, Apt. 1025, College Station, TX, 77840
Tel:  (979)-862-9113 (h), (979)-845-3238 (o)
Email addr:    yangk@ocean.tamu.edu; yangk@netease.com
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