Fracture analysis of tertiary carbonate reservoirs in Iraqi Kurdistan

UDK: 551.252
DOI: 10.24887/0028-2448-2022-5-13-18
Key words: structural geology, carbonate fractured reservoirs, fracture analysis, outcrop fracture data, tertiary reservoirs in Kurdistan, mathematical software utilization
Authors: H.M. Ali (Crescent Petroleum, Sulaymaniyah Office, Iraq, Sulaymaniyah), S.F. Khafizov (Gubkin University, RF, Moscow)

The Iraqi Kurdistan territory is considered a unique region for the the petroleum geology, due to the fact that, on the one hand, part of the reservoirs, for example, of the Cenozoic age, was formed in relatively deep sea conditions, and was present with low-permeability deposits, mainly argillaceous limestones, where the role of fracturing in enhancing the reservoirs cannot be overestimated, and on the other hand, provide a wide opportunities for studying all elements of petroleum systems, including the reservoir. This study is focusing on a group of formations of significant economic interest to the oil industry in Iraq, namely the Lower Fars, Jeribe and Pilla Spi formations of the main Cenozoic (Tertiary) age. The above-mentioned formations are believed to play an important role in natural hydrocarbon systems. Some of them are good reservoirs and other ones are cap rocks. The availability of the very well exposed reservoir rocks on the outcrop provides a possibility to implement a wide range of fracture analysis and use the results to better predict natural fracture characteristics of subsurface fracture network of the Tertiary reservoirs in all Iraqi Kurdistan fields. One of the practical and very useful analysis is to use mathematical computation method within a frame of the MATLAB software. A modern method that did not well credited yet in the oil and gas industry. In this paper we utilize a photogrammetry technique in integration with mathematical computation to extract the full set of fracture characteristics from outcrop. Such Method is just started to get spotlight in the Oil and Gas Industry and expected to gain more attraction by researchers in soon future.

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