Future Challenges For Producing Middle East Oilfields During Maturation Stage
Authors: Mahroos F. A. 
Published: December 2007

The maturation stage of an oil reservoir is irrespective of the producing time. It is the stage when the oil reservoir loses it's own energy which is usually coupled with drop in oil productivity and/or intrusion of aquifer water and gas cap gas. In case of assisted recovery schemes a third or fourth fluid will require to be added. The mechanism of adjustment between the reservoir rock and fluids with the new fluid added, irrespective of whether they are indigenous or extraneous usually complicates the oil production process. Certain rock characteristics such as secondary porosity, Super K, communicating faults, fractures etc. will further complicate the process. Management of an oilfield during this stage is completely different from that during the primary development stage.

The Middle East is undoubtedly the most important oil region in the world; it has two thirds of the world oil reserves and presently provides one third of the world's oil needs. Unlike most other oil regions in the world, the Middle East oilfields are still prolific. But, most are now approaching the end of their primary production stage. In some fields the oil production is assisted by water or gas injection. The huge amount of oil reserves and the state of its field make this area the oil hub of the world and its strategic reserve. Hence, it is necessary to understand the future challenges for the upstream industry, especially when the Middle East fields are no longer able to meet the demand on its oil, based on it's own energy.

This paper discusses the challenges, which will be faced by the Middle East Oil fields in maintaining oil production at the present rate or more and provides direction towards possible solutions.

The maturation stage of an oil reservoir is irrespective of the producing time. It is the stage when the oil reservoir loses it's own energy which is usually coupled with drop in oil productivity and / or intrusion of aquifer water and gas cap gas. In case of assisted recovery schemes a third or fourth fluid will require to be added. The mechanism of adjustment between the reservoir rock and fluids with the new fluid added, irrespective of whether they are indigenous or extraneous usually complicates the oil production process. Certain rock characteristics such as secondary porosity, Super K, communicating faults, fractures etc. will further complicate the process. Management of an oilfield during this stage is completely different from that during the primary development stage.

The Middle East area is undoubtedly the most important oil region in the world; it has two thirds of the world oil reserves and presently provides one third of the world's oil needs. Unlike most other oil regions in the world, the Middle East oilfields are still prolific. But, most are now approaching the end of their primary production stage (Figure: 1). In some fields the oil production is assisted by water or gas injection. The huge amount of oil reserves and the state of its field make this area the oil hub of the world and its strategic reserve. Hence, it is necessary to understand the future challenges for our upstream industry, especially when the Middle East fields are no longer able to meet the demand on its oil, based on it's own energy.

The main objective is the need to continue the oil production at the present rate, or more, so as to satisfy the ever-increasing financial needs of the region, while the productivity of our oilfields are declining because of the natural maturation process. The challenges can be summarized as follows: - The massive amount of operations required for maintaining oil production or even increasing it, as required. This will be a reflection of the number of wells to be drilled, workovers, stimulation, logging, coil tubing, cementing, pipelines, surface facilities, construction, inspection and maintenance operations etc. to be carried out.The environmental effect and the cost impact of the increasing rates of produced water and associated gas. This situation will be further aggravated by the increasing amounts of chemicals and additives being used for drilling, cementing, acidizing, separation and treatment processes.The characterization of the carbonate rock to identify bypassed oil and initiate enhanced recovery schemes such as water, gas, CO2 and steam floods; and horizontal drilling etc. will pose a major technological challenge.Developing and producing oil from tight oil reservoirs.