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Chapter 8 presents practical limitations ori- ented to discussion on interference and pulse testing. In relation to interference tests under the influence of wellbore storage and skin and pulse testing, the discussion clearly indicates the main limitations of presently available techniques: they are only applicable to homo- geneous and isotropic systems. The usefulness of interpreting tests of this nature through res- ervoir simulation is pointed out.

Chapter 9 presents the state-of-the-art the- ory on drillstem, closed chamber and slug tests. The differences of these test conditions with those of tests previously introduced (very short production period, variable production rate, small radius of investigation, significantly dif- ferent momen tum effects and frictional losses, etc. ) are emphasized. The lack of sufficient field data in support of theoretical results is in- dicated. Also, the preliminary nature of the re- sults acquired through these tests is addressed.

Finally, the author prepares the reader to understand future developments in well test- ing. His purpose is to enable the reader to read research papers with a good level of compre- hension. The discussion presented included the dimensionless form of the diffusivity equa- tion, and introduction to the Laplace trans- form and its numerical inversion, constant-rate solutions of the radial-flow diffusivity equa- tions, multilayered co-mingled reservoirs, nat- urally fractured reservoirs, slug testing, finite and infinite conductivity, hydraulically frac- tured wells and deconvolution. In summary, this excellent, updated, practical and limitations-oriented book will be found very useful by all petroleum engineers and ge- ologists working in industry and academia. The author's analysis of field case is particularly enlightening. This treatise is a "must" for all well-testing engineer's private collections and petroleum engineering related libraries.

F. SAMANIEGO (Mexico City, Mexico )

Well Test Analysis lot" Fractured Reservoir Evaluation, by Giovanni da Prat. Develop- ments in Petroleum Science, Vol. 27. Else- vier, Amsterdam, 1990, 210 pp., Dfl. 195.00, ISBN 0-444-88691-5.

It is well known that an important fraction of worldwide hydrocarbon reserves is found in naturally fractured reservoirs. Fluid flow in these systems is more complex than in conven- tional non-fractured formations for which the theory of fluid flow is at a more advanced level. Determinations of an optimal exploitation scheme for a fractured reservoir rests on the ability to adequately characterize this hetero- geneous system. That will be extremely impor- tant for performance prediction and for sec- ondary and enhanced recovery studies. The effort needed to accomplish this task is bigger than that required for conventional reservoirs, because two parts compose the porous me- dium, which are to be properly studied, i.e., the fractured and the matrix systems. A very im- portant contribution toward accomplishing a characterization of these reservoirs is pro- vided by the interpretation of well test data.

This book presents a thorough discussion of well-test analysis for naturally fractured reser- voirs. The author relies on his own experience and the vast literature available in this partic- ular area.

The contents of this book can basically be divided into three important topics related to well test interpretations: ( 1 ) Interpretation of pressure-transient tests

at constant flow rate. (2) Interpretation of constant-pressure pro-

duction test, including decline-curve analysis.

(3) Interpretation of interference tests. Chapter 1 presents a summary of well-test

analysis techniques, including a discussion of the pressure-derivative method and the anal- ysis of tests with simultaneous measurements of pressure and flow rate. Next, the character- istics of fractured reservoirs and the methods

used to identify these systems are presented in Ch. 2. It includes a summary on the different well-test models introduced over the past 30 years.

The succeeding three chapters deal with constant-rate analysis techniques. Chapter 3 presents the basic theory, including the fun- damental flow equations and a description of type curves. Next, Ch. 4 introduces the theory involved in the Homer analysis, in addition to a practical procedure for analyzing buildup tests in these systems. Chapter 5 presents the necessary theory and applications for the interpretation of interference tests.

The book also includes two useful chapters dealing with the interpretation of constant- pressure production tests. Chapter 6 discusses the fundamentals of constant-pressure pro- duction test analyses for naturally-fractured reservoirs, an important topic in the light of the present-day high-accuracy flow-rate mea- surements. Chapter 7 presents the fundamen- tal theory and applications for the analysis of intereference tests.

Finally, three specific chapters are included in the book that deal with important comple- mentary subjects. Chapter 8 describes a listed FORTRAN computer program for radial flow of a fluid in these systems, that can be used for the generation of type curves for particular test conditions. Chapter 9 analyzes the uses for pressure-transient single-well and multiple-well (interference) test to determine the fractured system extensions and fracture trends. Finally, Chapter 10 discusses the design aspects of the well tests already discussed in the book for naturally-fractured reservoirs.

In summary, this book presents an updated discussion of well-test analysis for naturally- fractured reservoirs, which should be very use- ful for all petroleum engineers working in in- dustry and academia. The examples presented throughout this text will be found particularly enlightening by the reader. This treatise must be present in all petroleum engineering and ge- ology libraries.

FERNANDO SAMANIEGO (Mexico City, Mexico)

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The Three-Dimensional Facies Architecture of Terrigenous Clastic Sediments and Its Im- plication for Hydrocarbon Discovery andre- covery, edited by A.D. Miall and N. Tyler. Concepts in Sedimentology and Paleontol- ogy, Vol. 3. SEPM (Society for Sedimen- tary Geology), $68 to SEPM members, $95 to non-members, 1991, 309 pp., ISBN 0- 918985-94-3.

There are many publications in the litera- ture that discuss the application of sedimen- tology to petroleum exploration and exploita- tion. However, this volume truly addresses the subject. Editors A. Miali and N. Tyler have as- sembled 26 original case history publications of siliciclastic rock units from around the world, from Devonian to Holocene age, that illustrate megafacies and microfacies attri- butes of depositional units to the detail where such information actually can be used by ex- ploitationists to understand and model silici- clastic reservoirs and productive zones within such reservoirs.

Three papers in the introductory section discuss architectural controls on the recovery of hydrocarbons from reservoirs in sand- stones, and the use of outcrop photomosaics as a means of resolving sedimentological details of siliciclastic deposits. Following, individual contributions address reservoirs in barrier-is- land, eolian, fluvial, deltaic and other coastal and shelf, and deep-water deposits. And therein is the main attraction of the volume: the separate papers are replete with details of reservoir occurrence, pay continuity and the three-dimensional architecture of productive zones within specific depositional facies, in- formation that is of paramount significance in considerations of enhanced recovery from res- ervoirs. All too often such detail is not avail- able to non-specialists in a readily useable for- mat, and accordingly, much sedimentological data of direct relevance to exploitationists never makes it into their hands. This volume is the exception in that it was assembled to be of particular benefit to engineers and devel- opment geologists.