I have used many structural indexes to calculate the depth gravimetric sources, but which one is more significant for fault and geologic contact? (I have chose si=0,0.5,1).
One way is to choose from your geologic setting. If you are studying of dyke-shaped vertical intrusions, perhaps the best index is the one that represents a vertical cylinder. If you are studying caves or a granite intrusion try with spheres.
Another way involves knowing a depth to one of your gravity sources. Lets say that you have an asymmetric body 200 m beneath the sediments. You can run the Euler Deconvolution for several values ( 0, 0.5, 1, 1.5, etc) and choose the best one that fits that depths. From there you can speculate that other depths are relatively well estimated.
I also think that there are other techniques like Werner Deconvolution that works better for faults and contacts.
Euler is a good method but be aware that sometimes it works better to find the lateral continuity of structures than actually to estimate their real depth (particularly in faults and contacts area). Try to compare your results against other methods (e.g. Power spectrum, Wenner, Inverse modelling, etc )
Analytic Signal is better for this type of problems because is kind of design for finding faults , Wiener is also good. Check the description of each method in: Richard J. Blakely's Book: Potential Theory in Gravity and Magnetic Applications. It might help you. Good luck!
THINK YOU MR MARIANO IN MY RESULTS I HAVE USE SI OF 0,0.5,1 and i have copare them to signal analytic resultats i have find thats SI =0 HAVE GOOD CORRESPONDANCE WITH AS RESULT WHAT DO YOU THINK AND I HAVE CHOOSE THIS VALOR OF SI TO DETECT LINEAMENT
Dear Oualid.
This sounds OK. Analytic Signal is design for faults and in Euler deconvolution SI=0 is the closest you can get to a fault/dyke.
You might check if the code you are using accepts negative values. I think the INTREPID code for Euler deconvolution treats SI=-1 as a contact/edge, but I am not sure of the validity of negative SI in the Euler formulation. Try that as well, Who knows, might help too.
Hello Oualid Melouah, a bit late but I think I can give some contribution. I think you should be more cautious before use any structural index on Euler deconvolution. Find a result is not the same as find the correct result.
Please take a look at: Reid, A.B. and Thurston, J. 2014. The structural index in gravity and magnetic interpretation: Errors, uses, and abuses. Geophysics VOL. 79, P. J61–J66.
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