Horacio Acevedo Personal Webpage |
This page was last updated on: November 14, 2007
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Horacio Acevedo M.S. in Geophysics Geological Eng. and Sciences Michigan Technological University 2008 D Woodmar Drive Houghton MI, 49931 current e-mail: horacioacevedo@yahoo.com Cels: +1-281-660-4117 +52-993-2074531 |
The purpose of this page was to show my advances in research, during the Master Program in Geophisics at Michigan Tech in 2001, see the paper in TLE October 2001. Then I work for a different project working in Seismic Inversion, see the paper in TLE November 2003. Personal Information and Resume was updated on Nov 2007. Now I am working for Fugro-Jason as the Principal Project Geoscientist for the south region in Mexico. |
Antecedent: - Teal South is located in Golf of Mexico with several small oil fields (brightspots). - Three 3D projects had been adquired, the first one was recorded using stremers (1995). The 2nd (1996) and 3rd (1998) were recorded using 4C OBC, and are named Phase 1 and 2. - Production start in 1995. - In this research Phases 1 and 2 had been consider. Goal: To quantify and analyze the differences in amplitude between the phases 1 and 2 in the sandstone called "4500' sand" and the small neighbor structure (1.4 to 1.5 sec), along the in-line 1140. The study was based in the analisys of pre-stack data, every 4 CDPs. Promax was used to obtain most of the results. Steps: - Data normalization: Partial Stacks for both of the phases. - CDP analysis in absolute value of offset (fig 1 and 2). - Time shift between Phase 1 and Phase 2. (fig 3) - CDP's normalization in four offset ranges and partial stacks. (fig 4 and 5) - Amplitude spectrums (Am Sp). - Comparison of Am Sp, between the two phases at different time windows and at different ranges of offset. (fig 6) - Comparison between the total values of amplitudes at targets (fig 7 to 10). - Analysis and conclusions. |
Fig 1 and 2: Example of a CDP gather with 2 different presentations. The right one represent the real offset distribution. |
Fig 3: Between the two phases a time shift of 3 ms exist. In the figure you can see the two phases plotted together, after the 3 ms time shift correction and fk filter. As you can see, this simple process given us a good normalization. |
Fig 4: CDP gathers after normalization in 4 different offset ranges. The figure show the CDPs 1132 to 1172 in phase 2. Four different offset ranges were figured out. The traces in every CDP in the figure, represent partial stacks between 0 to 8, 8 to 16, 16 to 24 and 24 to 32 degrees of angle of incidence between source and reseptor at target depth (4500' approx). |
Fig 5: Stack of the data in the offset range 16 to 24 degrees. Partial stacks were created for every offset range. |
Fig 6: Example of an Amplitude Spectrum. In this case it correspond to 600 to 900 ms, 8 to 16 degress offset range in phase 1. Am. Sp. as this were calculated for all the offset ranges, at 5 different time windows, including and not including the targets and for both of the phases. |
Phase 1 and 2 together, 0 to 8 offset degrees for the 4500' sandstone. |
Phase 1 and 2 together, 0 to 8 offset degrees for the 4500' sandstone. |
Phase 1 and 2 together, 8 to 16 offset degrees for the 4500' sandstone. |
Phase 1 and 2 together, 16 to 24 offset degrees for the 4500' sandstone. |
Phase 1 and 2 together, 24 to 32 offset degrees for the 4500' sandstone. |
Analisys and Conclutions: The Data has a poor offset distribution, because the geometry during the acquisition, in spite of that, was possible to normalize the two phases and analyze the pre-stack data using partial stacks in different ranges of offset, followed by a FK filter for remove high frequency noise. At 4500' sand, the amplitudes in Phase 2 are much bigger than in Phase 1, probably due to an expansion of the free gas cap as consequence of the oil produced during the time between the acquisitions of the two phases. Although there is not production in the "little neighbor" sand, the amplitudes of the west half in phase 2 are bigger than in phase 1. This observation could be explained if a communication between this small reservoir and the 4500' sand exist. The production in the 4500' sand can reduce the pressure in all the system and the free gas cap of the little neighbor could have been developed. For more information, including the resoults of the Amplitude Spectrum analisys and total values of the targest, please see the attached file teal south.ppt |
Thanks for read this page, I will appreciate your comments. |