There are at least two books in the Elsevier series (Elsevier Scientific Publishing So: "Fundamentals of Fractured Reservoir Engineering", author is Prof. T.D. van Golf Racht: Fundamentals of fractured reservoir engineering, Elsevier 1982; another with a title close to 'fractured reservoir transient analysis'. You could find them helpful.
I don't think the books are online. The first is an old book, and things have moved since it was written; the second sort of captured the state of the art when it was written; unfortunately, I'm unable to supply the full title of the second book. I'll suggest you check a library, preferably at an institution, or better still, you could check with Elsevier. Good luck.
In dealing with many of the US Rocky Mountain Fields, some simple questions come to mind.
- How does production data map out (are there bulls eyes?)
Production data analysis is one way to identify the unusual behaviour characterizing naturally fractured reservoirs. Once there is gas breakthrough (and depending on the structure you´re dealing with), there is usually a dramatic improvement parameters: GOR, pressure and production rate. The reservoir may begin to behave like one with some pressure support, the GOR will most likely drop due to the migration of gas via the fractures upstructure, and the expected dramatic increase in GOR after the bubble point is reached may not occur, or may be brief compared to what would be were the reservoir a conventional one. You probably should take a closer look at the structure, and analyze the production and pressure data for the field.
- How does well test analysis compare to matrix permeabilities?
The large difference between laboratory (core) permeability and well test permeability is usually diagnostic of a fractured reservoir. The variation is usually so large that the there is no mistake. For some North Sea fields, the well test permeability is 10 to 100 times the matrix (core) permeability. The ´improvement´ is attributed to the fracture network.
