Mineral deposit evaluation: A practical approach

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This omission is particularly disappointing when the cover of the book says "Past climatic and environmental change is of prime importance in understanding climatic change of today . . . . The main purpose of this study is to demonstrate the evidence for climatic change and how this affected vegetation and flora... ; also to show the methods which can be used to investigate past climatic change and its consequences. Rather than a theoretical treatment of climatic change, this book is a unique "case study" of an investigation of past climatic change". Inside the book, climate is barely mentioned and there are no entries in the index for climate, palaeoclimate, temperature, or the like. The book is most successful at providing "considerable detail to the landscape history of an upper minor tributary of the R. Wensum" (p. 96) and convincingly showing "the importance of field observation and careful recording of sections" (p. 2). It also clearly demonstrates the "importance of stratigraphy in the reconstruction of Pleistocene environments" (p. 2), Overall it does not read as a book. One of the chapters is only 1 / 2 a page! It reads more as a large reference research monograph one associates with the former style of

Philosophical Transacttons of the Royal Socie~' of London. It is a book strictly for the specialist interested in the extremely detailed stratigraphy of a small area. It is disappointing in that little attempt is made to put its fascinating results into a broader Quaternary palaeoecological or palaeoclimatological context. H.J.B. Birks, Bergen

Mining Geology Alwyn E. Annels, Mineral Deposit Et,aluatton: A Practical Approach. Chapman & Hall, London, U.K., x v + 4 3 6 pp. ISBN 0-41235290-7.

This is the first book attempting to provide in-depth treatment of the entire process of economic evaluation of ore deposits. It is intended as a text for undergraduate and graduate students of mining geology and mining engineering, and professionals already with a career in the mining industry. The titles of the eight chapters are: (1) Representation of mine data; (2) Mine sampling; (3) Ore-reserves by "classical methods"; (4) Geostatistical ore-reserve estimation; (5) Design and evaluation of open-pit operations; (6) Financing and financial evaluation of mining projects (by E.G. Hellewell); (7) Grade control; and (8) Ore-evaluation case histories. Individual chapters are followed by separate lists of references and bibliographies; more technical material is contained in appendices. In the preface, the author states that he has tried to present the material in such a way that it becomes intelligible to the average geologist, or engineer, who is perhaps daunted by the more mathematical approach to the topic of ore-reserves found in more specialist publications. The geologist in the mining industry should have a full understanding of the advantages and disadvantages of each technique so that a judgement can be made as to their applicability to a particular deposit m connection with the mining method proposed or used. Lack of this expertise often results in the ore-reserve calculations being undertaken at head-office, as number-crunching or a geometric exercise divorced from geology. Improved access to microcomputers or work stations with associated software can help mining geologists to perform three-dimensional modeling of mineral deposits and carry out ore-reserve calculations. Hovever, an extensive background in computer-oriented mathematical applications is required for this. A.E. Annels deals with mine design in situations where there is relatively little uncertainty because the ore has been discovered in a global way. Among the abilities he deems essential for the mining geologist,

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there is little mention of ore-finding capability. For this use must be made of geological concepts leading to geometrical projections and quantitative prognosis on the basis of limited information; e.g., data at the topographical surface augmented by relatively few boreholes. Under such conditions the answer can only be speculative but this uncertainty can be expressed in terms of probabilities and (wide) confidence intervals. In practice the more speculative predictions should be followed up by further exploratory drilling, systematic sampling and assaying, and ore reserve calculations. These types of problems are not addressed in the book. It is nearly impossible to produce the first edition of a book of this type without errors and inconsistencies. Some minor ones are as follows. In the chapter on mine sampling there is extensive discussion of Gy's formula for sampling reduction error variance with worked out examples. However, these presentations are based on early work and ignore post-1968 publications on the subject including P.M. Gy's book entitled "Sampling of Particulate Materials". Later m this chapter, the author confuses number of degrees of freedom (v) for Student's t-distribution with sample size (n). (In Table 2.2, p. 92, the rows are for v not n.) The semi-variogram value for lag equal to one is initially (on p. 93) written as S~. If S represents the standard deviation, an estimate of the corresponding autocorrelation coefficient would be r , = ( S 2 - S D2 ) / S "~~, and not the square root of this expression. The treatment of mathematical statistics could be improved significantly. For example, the author suggests that examination of normality (on p. 181) should take place according to 4 steps: (i) Chi-square test; (ii) log-probability plots; (iii) skewness, kurtosis and coefficient of variation (should be less than one) and (iv) data splitting in the case of blmodal populations. Much more discussion is needed here (or references), because the reader should not necessarily apply only these procedures in that order. (For exam-

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pie, what to do if the Chi-square test is passed, the log-probability plot is approximately a straight line and the coefficient of variation is equal to 0.8?) The treatment of geostatistical ore-reserve estimations also needs considerable improvement before it can be used by the reader. The mathematical explanations are sketchy and incomplete. On p. 215, the oddly complex equation 0.2 = Co/oo + C(o-~/C) is printed 5 times without mention that this is equivalent to o-Z = o-,~. I tried to check the worked example in section 4.14.3 where eight estimation variances o-Z are obtained for different sampling schemes (methods D to K) apphed to a block of length (l = ) 200 ft and height (h = ) 250 ft in an orebody for known spherical semi-variogram with range (a = ) 500 ft. By using the charts and tables in this book as can be done according to the author, I was able to get the same answers quickly for four methods only. For the others, the following problems were e n c o u n t e r e d . Method E: scale of h / a is off by factor 10 for h / a < 1 in Fig. A4.8; Method G: substitution of h / a = 0.5 and l/a = 0.4 into Fig. A4.10 gives o-,~/C = 0.028 (not 0.049 as in the text, which is for h/a = 0.4 and l/a = 0.5); Method H: Table A4.1 is incomplete in that it does not contain values for h / a < 1 and 1/a < 1; Method l: no graph or table for the auxiliary function X(1/a, h/a). The first two of these difficulties could be resolved by correcting for obvious errors; the last two could not be resolved because essential mformation is missing from the book. All answers could be obtained quickly by using a complete set of charts as, for example, provided in the book "Mining Geostatistics" by Journel and Huijbregts. The strength of this book is that it contains numerous interesting facts, explanations of methods and worked-out examples. To some extent, every mineral deposit is unique and this variety is captured by the presentation of a wide spectrum of carefully selected case history studies. The reviews of mining methods are comprehensive. The

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quality of the many illustrations is excellent throughout the book except for some partly illegible mine reserve plans (Figs. 8.31, 8.32) and poor reproduction of thin lines on graph paper (Figs. 8.35, 8.36). Because so many different topics are covered, access to the material in the book would be facilitated by the addition of more cross-referencing material. It would be relatively easy to print a more elaborate table of contents (including titles of subsections), an author index and a more elaborate subject index (only 3 pages at present). Perhaps these enhancements can be considered for the next edition. It is concluded that this book is very useful in many respects. Unfortunately, it needs thorough revision of the parts dealing with mathematical statistics and geostatistics before it can be fully recommended as a textbook. Frederik P. Agterberg, Ottawa, Ont.

Paleontology K. Carpenter and P.J. Currie (Editors), 1991. Dinosaur Systematics: Approaches and Perspectwes. Cambridge University Press, Cambridge, U.K. Hardcover. xiii + 318 pp., illus. Price: £ 4 0 / U S $54.50. ISBN 0-521-36672-0. Dinosaurs Viewed as Living Creatures If dinosaurs, or any other groups of extinct organisms, are to be studied as the living creatures they once were, the systematics of the extinct and living must be consistent. This extends to the level of species, viewed as the basic building blocks of systematics. This is the basic concept around which the symposmm reported in this volume was organized. The symposium entitled " T h e Dinosaur Systematic Symposium" was held in 1986 at the Tyrrell Museum of Paleontology, Drumheller, Alberta, Canada. Thirteen of the twenty eight papers presented form the core of the book. The symposium was dedicated to Charles C. Sternberg and a Fore-

word by Loris Russell reviews his work on the dinosaurs of Alberta, Canada. Following is a short Preface in which the purpose of the symposium is stated to be to examine sexual dimorphism, ontogeny, individual, variation and any other factors that may influence the taxonomic designation of a particular specimen of dinosaur. In the Introduction entitled "Systematics and Morphological Variation" by Carpenter and Currie the recurrent theme of variation is set in context. It is an extended review of the role that variation has played in the development of dinosaur systematics as the numbers and varieties of specimens have increased and concepts have changed as dinosaurs have come to be studied from a more strictly biological point of view. Each of the thirteen papers published in this book was peer reviewed and most were modified and updated following the original presentations. Some attack the central theme of the symposium expressed in the Preface directly, others tangentially, and some almost not at all. They are arrayed in nine sections or chapters. The first, Methods, includes two papers. The first of these, Clades and grades in dinosaur systematics, Paul Sererno analyzes in some detail the uses that have been made of each two approaches in studies of dinosaur and presents the bases for his support of a strictly cladistic system in dinosaur systematics. In the second paper, Shape analysis in the study of dinosaur morphology, Ralph E. Chapman explains and illustrates morphometric and shape analysis by analyses of carnosaur crania, of ontogeny in Bagaceratops, of sexual dimorphism in Protoceratops, of asymmetry in Plateosaurus plus a complex analysis of crania of several genera of pachycephalosaurids. Morphometrlc techniques are also used in a study of Plateosaurus by Weishampel and Chapman in section II and by Goodwin in his analysis of pachycephalosaurid cranial material in section V. Sections II through VIII treat in sequence systematic problems of taxa within the Sauropodomorpha, Theropoda, Ornithopo-