Sensitivity study of TEM data at La Bajada Fault Tobyn W. VanVeghten University of Missouri-Rolla July 11, 2004
Outline Objective Methodology with example 1-D results TEM Cross-section constrained by sensitivity analysis WinGLink EMMA and results from EMMA Conclusion
Objective Sensitivity analysis –Constrain TEM data at Canyon Site Qualitatively in WinGLink Quantitatively using EMMA
Examples of Raw Data
Sensitivity Test
Sensitivity Test Cont’d
Inverse Models with Error Bars
TEM Cross-Section E W
EMMA Electromagnetic Model Analysis (EMMA) Program Developed by the HydroGeophysics Group, University of Aarhus, Denmark 1-D modeling program for most TEM, FDEM, Resistivity, MT, and borehole methods Includes model sensitivity analysis *From Auken, Nebel, Sorensen, Breiner, Pellerin, and Christensen, June 2002
EMMA Screenshot
Example of EMMA Results Earlier Results for Comparison
TEM Cross-Section after EMMA EW
Conclusion Can’t resolve top and bottom resistive layers Change in character between LB600 and LB650 Possible fault here