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Hydrothermal uranium deposits. Developments in economic geology, 6
Chemical Geology, 22(1978) 87--90 © Elsevier Scientific Publishing Company, Amsterdam,-- Printed in The Netherlands
87
Book Reviews
Hydrothermal Uranium Deposits. Developments in Economic Geology, 6. R o b e r t A. R i c h , H e i n r i c h D. H o l l a n d and Ulrich Petersen. Elsevier Scientific Publishing Co., A m s t e r d a m - - O x f o r d - - N e w Y o r k , N.Y., 1 9 7 7 , 264 pp., Dfl.85.00/US $34.75.
T h e b o o k is divided i n t o t w o m a j o r p a r t s : (1) g e o l o g y , g e o c h e m i s t r y a n d origin o f h y d r o t h e r m a l u r a n i u m d e p o s i t s (pp. 1 - - 7 6 ) ; and (2) d e s c r i p t i o n s of h y d r o t h e r m a l u r a n i u m d e p o s i t s (pp. 7 7 - - 2 3 0 ) . T h e s e are f o l l o w e d b y an " A u t h o r i n d e x " (pp. 2 3 1 - - 2 3 8 ) , and " S u b j e c t i n d e x " (pp. 2 3 9 - - 2 6 4 ) . It is clearly s t a t e d t h a t this b o o k is e n t i r e l y d e v o t e d " t o h y d r o t h e r m a l uran i u m deposits. I t p r o v i d e s a s u m m a r y o f t h e i r g e o l o g y , m i n e r a l o g y a n d geoc h e m i s t r y a n d discusses genetic m o d e l s f o r t h e i r o r i g i n " . It m u s t t h e r e f o r e b e u n d e r s t o o d t h a t this is n o t a general b o o k on u r a n i u m d e p o s i t s or u r a n i u m g e o c h e m i s t r y . In t h e i r p r e f a c e , the a u t h o r s t h e m s e l v e s state: "Most of the uranium in the United States has come from "Colorado Plateau" and "Wyoming roll front" sandstone-type deposits. Hydrothermal uranium deposits i.e. deposits which occur as discordant veins stockworks, breccia zones, and irregular bodies of metasomatized rock, account for only about 4% of the total U.S. production plus reserves, but these deposits have been major and even dominant sources of uranium in Canada, Europe, Australia and Zaire." However, the distinction between "hydrothermal uranium deposits" and " s e d i m e n t a r y u r a n i u m d e p o s i t s " is difficult. T h e a u t h o r s t h e m s e l v e s state: "In the course of our literature search and field work we have become impressed with the geochemical similarities between hydrothermal uranium deposits and uranium deposits in sandstones. It seems likely that in the formation of both types of deposits uranium in transported in oxidizing solutions and deposited in response to its reduction from the hexavalent to the tetravalent state". Because o f this r e s t r i c t i o n , clearly d e f i n e d b y t h e a u t h o r s , t h e r e is a l o t o f q u e s t i o n s c o n c e r n i n g the n e a r - s u r f a c e m o v e m e n t of u r a n i u m in t h e crust, w h i c h is left u n a n s w e r e d . T h u s u r a n i u m in m e t a m o r p h i c rocks, w h i c h m u s t be e x t r e m e l y significant t o t h e q u e s t i o n o f h y d r o t h e r m a l u r a n i u m deposits, is o n l y c o m m e n t e d o n in a small s u b c h a p t e r o f five lines: "The uranium content of metamorphic rocks is quite variable, and tends to reflect the uranium concentration of their protoliths. However, some very high-grade metamorphic rocks are apparently depleted in uranium relative to their lower grade and unmetamorphosed equivalents, and it is possible that uranium moves upward in the crust during granulite grade metamorphism (e.g. Heier and Adams, 1965)."
88 One would have expected something more of a b o o k published in 1977. However, if one has this very clear definition in mind "the b o o k only discusses literally true hydrothermal deposits", it is of high quality. Following the general discussion case studies are reported from: (1) Canada. (2) United States. (3) Australia (Darwin Region and Mary Kathleen). (4) Central Europe. (5) Western Europe. (6) Gabon. (7) South West Africa (R0ssing Deposit). (8) Zaire. Bearing in mind the restriction on the scope of the b o o k which is very clearly defined by the authors themselves, it is very strongly r e c o m m e n d e d reading. It is a necessary reference source for everybody working or interested in uranium geochemistry. The b o o k is number six in Elsevier's series on Developments in Economic Geology. It very clearly defends its place and it is to be h o p e d that this series continues along the lines so far marked out. KNUT S. HEIER (Trondheim)
The Evolution o f the Crystalline Rocks. D.K. Bailey and R. Macdonald (Editors). Academic Press Ltd., London, 1976, 484 pp., UK £ 1 6 . 0 0 / U S $35.00. This b o o k is described by the editors as a sequel to Bowen's classic The Evolution o f the Igneous Rocks (1928), and it represents "a team effort to bridge that gap" between Bowen's b o o k and modern developments in experimental petrology. This task was a vast one and decisions had to be made regarding which rock groups and systems would be discussed. Readers looking for a comprehensive treatment will be disappointed to find little relating to the broad area of basic magmatism, a topic the editors feel "is more than adequately represented in recent literature". Also omitted is any systematic discussion of mantle petrology. What is covered includes the major groups of metamorphic rocks and the experimental petrology of granites and alkaline rocks. Part I of the b o o k (97 pp.), by Bailey, includes a brief introduction to the methods of experimental petrology followed by a lengthy discussion of the uses of phase diagrams. The latter includes a particularly good treatment of solid--solid equilibria and of the influences of vapour phases on solid and soli d - l i q u i d phase relations. A central theme for the b o o k is established in the warnings accompanying the discussion of the difficulties inherent in diagrammatic portrayal of p o l y c o m p o n e n t systems and of the ambiguities of various
87
Book Reviews
Hydrothermal Uranium Deposits. Developments in Economic Geology, 6. R o b e r t A. R i c h , H e i n r i c h D. H o l l a n d and Ulrich Petersen. Elsevier Scientific Publishing Co., A m s t e r d a m - - O x f o r d - - N e w Y o r k , N.Y., 1 9 7 7 , 264 pp., Dfl.85.00/US $34.75.
T h e b o o k is divided i n t o t w o m a j o r p a r t s : (1) g e o l o g y , g e o c h e m i s t r y a n d origin o f h y d r o t h e r m a l u r a n i u m d e p o s i t s (pp. 1 - - 7 6 ) ; and (2) d e s c r i p t i o n s of h y d r o t h e r m a l u r a n i u m d e p o s i t s (pp. 7 7 - - 2 3 0 ) . T h e s e are f o l l o w e d b y an " A u t h o r i n d e x " (pp. 2 3 1 - - 2 3 8 ) , and " S u b j e c t i n d e x " (pp. 2 3 9 - - 2 6 4 ) . It is clearly s t a t e d t h a t this b o o k is e n t i r e l y d e v o t e d " t o h y d r o t h e r m a l uran i u m deposits. I t p r o v i d e s a s u m m a r y o f t h e i r g e o l o g y , m i n e r a l o g y a n d geoc h e m i s t r y a n d discusses genetic m o d e l s f o r t h e i r o r i g i n " . It m u s t t h e r e f o r e b e u n d e r s t o o d t h a t this is n o t a general b o o k on u r a n i u m d e p o s i t s or u r a n i u m g e o c h e m i s t r y . In t h e i r p r e f a c e , the a u t h o r s t h e m s e l v e s state: "Most of the uranium in the United States has come from "Colorado Plateau" and "Wyoming roll front" sandstone-type deposits. Hydrothermal uranium deposits i.e. deposits which occur as discordant veins stockworks, breccia zones, and irregular bodies of metasomatized rock, account for only about 4% of the total U.S. production plus reserves, but these deposits have been major and even dominant sources of uranium in Canada, Europe, Australia and Zaire." However, the distinction between "hydrothermal uranium deposits" and " s e d i m e n t a r y u r a n i u m d e p o s i t s " is difficult. T h e a u t h o r s t h e m s e l v e s state: "In the course of our literature search and field work we have become impressed with the geochemical similarities between hydrothermal uranium deposits and uranium deposits in sandstones. It seems likely that in the formation of both types of deposits uranium in transported in oxidizing solutions and deposited in response to its reduction from the hexavalent to the tetravalent state". Because o f this r e s t r i c t i o n , clearly d e f i n e d b y t h e a u t h o r s , t h e r e is a l o t o f q u e s t i o n s c o n c e r n i n g the n e a r - s u r f a c e m o v e m e n t of u r a n i u m in t h e crust, w h i c h is left u n a n s w e r e d . T h u s u r a n i u m in m e t a m o r p h i c rocks, w h i c h m u s t be e x t r e m e l y significant t o t h e q u e s t i o n o f h y d r o t h e r m a l u r a n i u m deposits, is o n l y c o m m e n t e d o n in a small s u b c h a p t e r o f five lines: "The uranium content of metamorphic rocks is quite variable, and tends to reflect the uranium concentration of their protoliths. However, some very high-grade metamorphic rocks are apparently depleted in uranium relative to their lower grade and unmetamorphosed equivalents, and it is possible that uranium moves upward in the crust during granulite grade metamorphism (e.g. Heier and Adams, 1965)."
88 One would have expected something more of a b o o k published in 1977. However, if one has this very clear definition in mind "the b o o k only discusses literally true hydrothermal deposits", it is of high quality. Following the general discussion case studies are reported from: (1) Canada. (2) United States. (3) Australia (Darwin Region and Mary Kathleen). (4) Central Europe. (5) Western Europe. (6) Gabon. (7) South West Africa (R0ssing Deposit). (8) Zaire. Bearing in mind the restriction on the scope of the b o o k which is very clearly defined by the authors themselves, it is very strongly r e c o m m e n d e d reading. It is a necessary reference source for everybody working or interested in uranium geochemistry. The b o o k is number six in Elsevier's series on Developments in Economic Geology. It very clearly defends its place and it is to be h o p e d that this series continues along the lines so far marked out. KNUT S. HEIER (Trondheim)
The Evolution o f the Crystalline Rocks. D.K. Bailey and R. Macdonald (Editors). Academic Press Ltd., London, 1976, 484 pp., UK £ 1 6 . 0 0 / U S $35.00. This b o o k is described by the editors as a sequel to Bowen's classic The Evolution o f the Igneous Rocks (1928), and it represents "a team effort to bridge that gap" between Bowen's b o o k and modern developments in experimental petrology. This task was a vast one and decisions had to be made regarding which rock groups and systems would be discussed. Readers looking for a comprehensive treatment will be disappointed to find little relating to the broad area of basic magmatism, a topic the editors feel "is more than adequately represented in recent literature". Also omitted is any systematic discussion of mantle petrology. What is covered includes the major groups of metamorphic rocks and the experimental petrology of granites and alkaline rocks. Part I of the b o o k (97 pp.), by Bailey, includes a brief introduction to the methods of experimental petrology followed by a lengthy discussion of the uses of phase diagrams. The latter includes a particularly good treatment of solid--solid equilibria and of the influences of vapour phases on solid and soli d - l i q u i d phase relations. A central theme for the b o o k is established in the warnings accompanying the discussion of the difficulties inherent in diagrammatic portrayal of p o l y c o m p o n e n t systems and of the ambiguities of various