From jcarcione@ogs.trieste.it Fri May 8 11:51:01 2009 Date: Thu, 7 May 2009 09:51:25 +0200 From: Jose' M. Carcione To: Juan E Santos Cc: Stefano Picotti , Jose' Carcione Subject: Re: fractures + oscillatory tests [ The following text is in the "ISO-8859-1" character set. ] [ Your display is set for the "US-ASCII" character set. ] [ Some characters may be displayed incorrectly. ] Juan, > > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > I do not understand the question here. What you mean by a viscoelastic > code? you mean the same oscillatory experiments but instead of each layer > being poroelastic they are elastic? I do not have such a code, but may > bee written by Stefano. An whcih would be the dissipative mechanism? > in our case is the presence of gas patches, for example. > > I also do not know how to include the angle of incidence in the > oscillatory code. Now we impose either normal or tangential stresses > on the top bry for the compression and on the top an lateral bries for the > shear test. > > Can you explain what you need more in detail? > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > I mean viscoelastic modeling. Each layer is isotropic and viscoelastic. The viscoelasticity can be described by memory variables or by using any general frequency dependence if the modeling works in the frequency domain. Such experiments can be done by using wave propagation as we did in the past. Using oscillatory tests, we could impose normal stresses at the top and the bottom of the sample and rotate the symmetry axis (stratification) of the medium with respect to the horizontal plane. Then, we have to find the relation between this angle and the energy or ray angle Is it possible? > > or you mean a code for viscoelastic wave propagation? > I do have such a code. > Yes. > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > I assume by single phase media you mean elastic media, no fluids, or > Gassmann at the most. > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Viscoelastic media with QP and QS using phenomenological models, Zener, etc. > &%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > I think it is perfect, but we need to clarify the points I described > above (I mean I do not know exactly what you need as an oscillatory code) > > Then we need the people that is going to work in the theory and in the > codes, I can write the algebraic problems for a code, but implementing and > debugging, I simply have no time for that, we need youger people. > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Stefano and Davide Gei could work on these experiments. Then, we can find other people experienced in modeling. -- Jose' ------------------------------------------------- This mail sent through IMP: http://horde.org/imp/