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Chevron Gulf of Mexico Faulted Data

Figure [*] is an image of faulted Gulf of Mexico data. When a significant discontinuity occurs within a data-set, local dip estimators return incorrect estimates. Faults with significant displacement contaminate the dip estimation at the faults. This, in turn, results in unsatisfactory flattening results.

We use the crude binary weight cube shown in Figure [*] to identify areas where the inversion should ignore incorrect dips. This weight was created by manual picking. It should be noted that a suitable weight can also, in principle, be made from an automatic fault detector.

The flattening results are shown in Figure [*]. Notice that the horizons are flat, even directly across from the fault. Also, notice the presence of a channel in the horizon slice. Figure [*] shows the original data with one unflattened horizon overlying it. It successfully tracks the horizon even across the fault. The time slice at the top of Figure [*] shows a horizon that is being partially cut by the fault at about x=$2600\ m$.

 
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Figure 10
Faulted Chevron Gulf of Mexico data. The 2D vertical section shows fault with significant displacement (enough to cause our dip estimator to return erroneous values). (a) The time slice at time=$1.32\ s$. (b) An in-line section at y=$2693\ m$. (c) A cross-line section at x=$2348\ m$.
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Figure 11
A weight identifying the faults data displayed in [*]. (a) The time slice at time=$1.32\ s$. (b) An in-line section at y=$2693\ m$. (c) A cross-line section at x=$2348\ m$.
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Figure 12
The result of flattening of Figure [*]. (a) The horizon slice at time=$1.32\ s$. (b) An in-line section at y=$2693\ m$. (c) A cross-line section at x=$2348\ m$.
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Figure 13
The result of overlaying a tracked horizon on the image in Figure [*]. (a) The time slice at time=$1.28\ s$. (b) An in-line section at y=$2693\ m$. (c) A cross-line section at x=$2348\ m$.
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next up previous print clean
Next: Discussion Up: examples of 3D flattening Previous: Elf North Sea Unconformity
Stanford Exploration Project
5/3/2005