Citation :

Yasir F. Shyaa, "An Amplitude Variation with Offset (AVO) Analysis of a Selected Profile of the Jeribe Fn. (Middle Miocene) In the Khashim Al-Ahmer Field in the Northeast of Iraq.," International Journal of Geo-informatics and Geological Science, vol. 13, no. 3, pp. 1-10, 2026. Crossref, https://doi.org/10.14445/23939206/IJGGS-V13I3P101

Abstract

Applying the Amplitude Variation with Offset (AVO) technique to the Jeribe Formation (Miocene) in the Khashm Al-Ahmar field. The field is located in Diyala Governorate in the northeastern part of Iraq. One well in the study area (Ka2) penetrated the required reservoirs within the Jeribi Formation (Middle Miocene). The synthetic seismogram was created to correlate well with the seismic data, which shows a good match using the extracted well waves. The Hampson-Russell HRS-9 technique was used for processing the 2D pre-stack seismic data, Common Depth Points (CDP). The log data of one well, Khashm Al-Ahmar 2 (Ka2) and 2D pre-stack seismic data were used. Initially, the petrophysical study of the well Khashm Al-Ahmar 2 (Ka2) was conducted to predict the gas zone in the reservoir at the well site. Then, the zones far from the well were predicted by correlating the seismic data with the well. The Jeribe reservoir model with saturation levels of 60% gas, 20% brine, and 20% oil was used to replace the in-situ fluid saturation level in the analysis of the Amplitude Variation with Offset (AVO) behavior. The result of this research shows that the Jeribe reservoir in the Khashm Al-Ahmar field contains Class-3 gas, according to the AVO response under the in-situ conditions.

Keywords

The Jeribe Gas Reservoir, AVO Analysis, Bright Spots, CDP Gathers, Class-III.

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