Fractured reservoirs hold a substantial share of world reserves, concentrated in carbonate provinces but present in every rock type. They are recognised by their behaviour before they are recognised by their description: wells that produce at rates far above what matrix permeability could support, pressure that equalises across large distances almost instantly, water that arrives at a producer within weeks of injection starting, and recovery factors that stall at values the matrix properties do not explain.

The engineering difficulty is that the fracture network cannot be characterised directly at reservoir scale. Core shows fractures at centimetre scale in a sample that may or may not be representative and that was almost certainly damaged during recovery. Image logs show fracture intersections with the borehole, which is a one dimensional sample of a three dimensional network. Well tests give an effective permeability that is dominated by fractures but says nothing about their geometry. Production data reveals connectivity after the fact. Every characterisation is therefore inferential, built by combining evidence from different scales, and the resulting description must be tested against dynamic behaviour rather than assumed correct.

Recovery is where the consequences become expensive. In a water-wet fractured reservoir, water entering the fracture system imbibes into the matrix and displaces oil, and recovery can be good. In a mixed or oil-wet system, imbibition is weak or absent, water bypasses the matrix through the fracture network, and the field produces water while the matrix remains full of oil. Gravity drainage can be highly effective given sufficient block height and vertical continuity, and negligible where blocks are small. The difference between these outcomes is enormous, it is set by rock and fluid properties rather than by operational choice, and establishing which one applies is among the most valuable analyses that can be performed on a fractured field.

By the end of this training, participants will be able to:

• Describe fracture origin, geometry and the parameters used to characterise a fracture network
• Integrate core, image log, well test, production, seismic and analogue data into a fracture description
• Distinguish dual porosity, dual permeability and single medium behaviour from dynamic evidence
• Determine storativity ratio and interporosity flow coefficient from well test analysis
• Quantify matrix-fracture transfer including capillary imbibition, gravity drainage and diffusion
• Assess the effect of wettability and block size on recovery from the matrix
• Interpret production behaviour, decline characteristics and early water and gas breakthrough
• Select modelling approaches appropriate to the fracture system and the study objective
• Evaluate recovery mechanisms including depletion, waterflooding and gas injection in fractured systems
• Design surveillance and management practices suited to fractured field production

The course is delivered as a technical programme that moves from fracture characterisation to production management, treating the fractured system as a two-medium problem throughout. Each concept is developed through its physical mechanism and then applied to field data from fractured carbonate and clastic reservoirs. Case material includes fields where fracture behaviour was recognised late and the development suffered, and fields where matrix contribution was correctly assessed and recovery matched expectation. The limits of characterisation are addressed directly, since fracture descriptions are always partly inferred.

Organisations sending participants to this training will:

• Avoid development decisions based on reservoir descriptions that ignore fracture behaviour
• Improve recovery forecasts and reserves estimates for fractured assets
• Anticipate and manage rapid water and gas breakthrough rather than reacting to it
• Select recovery methods suited to the matrix-fracture system rather than to a conventional analogue
• Design fracture characterisation and surveillance programmes that deliver usable information
• Reduce the risk of injecting into a fracture network that bypasses the oil

Participants will:

• Recognise fractured reservoir behaviour from dynamic evidence
• Build a fracture description from the data actually available
• Quantify matrix contribution and its dependence on wettability and block size
• Interpret well tests and production data from fractured systems correctly
• Select and justify modelling and recovery approaches for fractured fields
• Take technical responsibility for a fractured asset

• Reservoir engineers working on fractured or suspected fractured fields
• Development and production geologists in carbonate and fractured provinces
• Petrophysicists interpreting fractures from image and conventional logs
• Simulation engineers modelling dual porosity systems
• Production engineers dealing with early breakthrough and conformance in fractured fields
• Well test analysts interpreting fractured reservoir responses
• Subsurface team leads and technical managers responsible for fractured assets

Upon successful completion of this training course, delegates will be awarded an official Certificate of Completion issued by the Petroleum Engineers Association (PEA), an ISO 9001:2015 certified training organization. The certificate carries 10 Credits and formally records the total learning hours completed.

Each certificate is signed by the Course Facilitator and the CEO of the Petroleum Engineers Association, and serves as verifiable proof of professional training that delegates can present to employers and professional bodies worldwide.