<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">Hi Brad,<DIV><BR class="khtml-block-placeholder"></DIV><DIV>I'm sure this has been taken into account somehow, but when comparing to the analytical results, we need to make sure that we don't actually use any values that lie on the fault, since the analytical solution blows up there. If we set the analytical results to zero along the fault, there will still be an error. I'm not sure how to deal with this problem, other than to shift all the values slightly off the fault.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Charles</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV><BR><DIV><DIV>On Aug 25, 2006, at 8:10 PM, Brad Aagaard wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Hi all:</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I have started tabulating the results for the Reverse Slip without<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Gravity benchmark. PyLith and GeoFEST produce nearly identical<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">results, as expected. The integrated L2 errors in the elastic<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">displacements for the 1000m resolution simulations are 1.6791e+05 and<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">1.6793e+05 for PyLith and GeoFEST, respectively. So... PyLith "wins"<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">by a micron. The integrated L2 norm difference between the two<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">elastic solutions from PyLith and GeoFEST is 1.0587e+03. At this<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">point, about all we can say is that PyLith and GeoFEST agree >100<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">times better with each other than they do with the analytical<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">solution.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Next steps: Comparing the displacements and velocities for the<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">viscoelastic relaxation, examining (plotting) the local error, and<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">calculating the errors for the 500m resolution simulations.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Brad</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">CIG-SHORT mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:CIG-SHORT@geodynamics.org">CIG-SHORT@geodynamics.org</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="http://geodynamics.org/cgi-bin/mailman/listinfo/cig-short">http://geodynamics.org/cgi-bin/mailman/listinfo/cig-short</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> </BLOCKQUOTE></DIV><BR><DIV> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">Charles A. Williams</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">Dept. of Earth & Environmental Sciences</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">Science Center, 2C01B</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">Rensselaer Polytechnic Institute</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">Troy, NY<SPAN class="Apple-converted-space"> </SPAN>12180</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">Phone:<SPAN class="Apple-converted-space"><SPAN class="Apple-converted-tab"> </SPAN></SPAN>(518) 276-3369</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">FAX:<SPAN class="Apple-converted-space"><SPAN class="Apple-converted-tab"> </SPAN></SPAN>(518) 276-2012</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">e-mail:<SPAN class="Apple-converted-space"><SPAN class="Apple-converted-tab"> </SPAN></SPAN><A href="mailto:willic3@rpi.edu">willic3@rpi.edu</A></FONT></P> <BR class="Apple-interchange-newline"> </DIV><BR></DIV></BODY></HTML>