Aligned porosity, near-angle P-P azimuthal amplitudes, and oil production
- Heloise Lynn (Lynn Inc.) | William Nicholas Goodway (Consultant)
- Document ID
- Society of Exploration Geophysicists
- SEG International Exposition and Annual Meeting, 15-20 September, San Antonio, Texas, USA
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Exploration Geophysicists
- Porosity, Fractures, Reservoir characterization, AVO/AVA, Anisotropy
- 3 in the last 30 days
- 3 since 2007
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P-P reflection amplitudes vary by offset and by azimuth in the presence of one set of vertical aligned fractures. At a boundary wherein the orthorhombic axes are misaligned by 70o at a shale-carbonate boundary, simple models of azimuthal (az’l) P-P amplitudes do not apply. This paper presents oil production data as evidence of aligned (or azimuthal or fracture) porosity connected to the borehole (fracture porosity) in an onshore naturally-fractured carbonate oil reservoir. The change with azimuth of the near-angle amplitudes (6-15o) and the AVA gradient (amplitude variation with angle, AVAz) have been calculated and displayed and tied to oil production data. The industry standard az’l amplitude measurement, AVAz, ties the oil calibration data moderately. The az’l variation of the near-angle amplitude data ties the oil production data quite well. Aligned porosity (fracture porosity) causes az’l P impedance. The az’l variation of the near-angle amplitudes is the response to az’l P impedance.
Presentation Date: Monday, September 16, 2019
Session Start Time: 1:50 PM
Presentation Time: 4:20 PM
Presentation Type: Oral
|File Size||3 MB||Number of Pages||5|
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