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Drift exploration in the canadian cordillera
88
Book rwiw.t
case history each from Canada, France, Scotland, Spain and Wales. The International Association of Exploration Geochemists has, since its inception, had a large and active group of members in North America, so the paucity of contributions from that part of the world is particularly surprising. The second omission is the lack of any mention of the current widespread use of glacial sediments, of various types, as sampling media in diamond exploration. Since this type of exploration depends on the retrieval of kimberlite indicator mineral grains from, rather than on chemical analyses of, the samples collected, it may not, perhaps, be considered as geochemical exploration, in the strictest sense, but is obviously a closely related topic. A thorough understanding of the modes of transportation and deposition of glacigenic regoliths is essential for those engaged in diamond exploration; it would, therefore, have been appropriate to have included, in this volume, some discussion of the particular problems they are likely to encounter. Glen Sinclair Toronto
Drift Exploration in the Canadian Cordillera. P.T. Bobrowsky, S.J. Sibbick, J.M. Newell and P.F. Matysek (Editors). British Colombia Ministry of Energy, Mines and Petroleum, Victoria, B.C., 1995, 504 pp., Can.$40.00. Exploration for mineral resources in areas covered by unconsolidated sediments of varying complexity and thickness places special demands on the methods used. Glaciated terrain is known to be a very distinctive field in exploration and within a given glaciated terrain, mountainous areas such as the Canadian Cordillera constitute a separate unit. Canadian geologists have realized that working in mountainous terrain dominated by Quatemary deposits requires a change in exploration strategy. In the foreword the mineral exploration in editors state: “Successful Quatemary-dominated terrain requires an appreciation and understanding of the surficial sediment cover, glacial history, glacial dispersal theory and soil formation, which can assist in the interpretation
of the overburden cover.” For a Quatemary geologist who has worked in exploration in northern Europe (Scandinavia and Finland) for more than twenty years this is nothing new. But to get an exploration geologist with a different kind of background or speciality to appreciate this fact seems to be as difficult in Canada as it has been in Europe. This collection of case histories provides many ideas for geologists working in the glaciated terrain to think about. The volume is a compilation of papers on various aspects of exploration in glaciated areas, mostly from British Columbia. This is an area in which numerous glacial phases have been recognized and where, therefore, patterns of glacial dispersion as well as thickness of till cover and types of moraine deposits vary throughout the whole province. Moreover, the variable topographic relief of this mountainous terrain brings an additional special feature to prospecting. Papers in the volume are grouped thematically, which assists the reader in finding those which are close to his/her speciality. Altogether 25 papers are included in the volume, most of them dealing with Quatemary geological problems and geochemistry. However, the three papers concerning the use of geophysical methods form a useful addition. Topics are diverse, and cover many principles of surficial geology such as recognition of paleo-flow direction, drift potential mapping, methods of drilling as well as glacial dispersal using indicator clasts. Geochemical contributions address various methods of till geochemistry and biogeochemical sampling, lake sediment research, laboratory techniques and new research interests such as partitioning studies. Geophysical papers deal with shallow seismic methods, borehole analysis and resistivity mapping. The papers include an abundance of illustrations, maps, graphical presentations and photos. Therefore the overall style is modem and makes the book easy to read, which is a good thing for a busy reader. However, an improvement in the quality of diagrams would make it even more easier to read. All too often overly sophisticated methods for the interpretation of results are used in these kinds of papers, but in the present case the authors can be congratulated for concentrating only on the essential things needed in every day prospecting. Exploration geologists from the glaciated terrain
Book twiews
of Europe are very familiar with problems discussed in this volume and they have written a huge number of papers on these topics during past twenty years. It seems to me, however, that the authors are not aware of those European publications. This is not only the fault of the authors of this volume, but is a very common problem among scientists today, namely not having time to read what colleagues in other parts of the world have already done. Instead, however, they do have time and money to do and write the same things again and again. Of course every study area has its own distinguishing features that have to be taken into account in the way that has been done in this project, but glaciated terrain also shares many common features irrespective of location. My opinion is, that discussing common problems and distinctive features at congresses, workshops, and seminars with colleagues from other parts of the world would save a lot of money for new research work instead of repeating the same work over and over. The papers included in the volume give a good background to the problems encountered when prospecting in glaciated terrain. They are written in a style that an ordinary prospector can understand. As such it could be recommended to be used as a textbook even in universities, and other schools giving education in exploration. Reijo Salminen Espoo
The following books of specialized interest have been received and are given brief reviews. Geofluids: Origin, Migration and Evolution of Fluids in Sedimentary Basins. J. Parnell (Editor). The Geological Society, London, 1994, 372 pp., US$lO8.00. The migration of water through sedimentary materials is generally recognized as a key phenomenon in diagenesis, transport of metals and petroleum, heat flow, and other processes. Of particular interest among the 21 chapters are those on metamorphic fluids in ore formation (Phillips et al.), origin of saline fluids in sedimentary basins (Hanor), fluid chemistry and hydrology in geothermal and gold
89
depositing systems (Nicholson), role of geopressure zones in MVT genesis (Fowler), fluid-rock interaction in redbeds as related to mineralization (Metcalfe et al.) and recognition of thermal effects of fluid flow in sedimentary basins (Duddy et al.). An Introduction to Mining Seismology. S.J. Gibowicz and A. Kijko. Academic Press, 1994, 399 pp., US$69.95. Disturbances related to mining can cause seismic events with magnitudes exceeding 4. The most severe seismic events are rockbursts, but seismic networks in major mining districts record more than 100 events per year. This book discusses generation, transmission and measurement of seismic events related to mining, and methods of using this data. Volcanism Associated with Extension at Consuming Plate Margins. J.L. Smellie (Editor). The Geological Society, London, 1994, 293 pp., US$lOO.OO. The papers in this book provide evidence that subducting plates are commonly subject to extension, and that arc volcanism is associated with this extension rather than with compressional tectonics. The chemistry and character of the resulting volcanics are documented for numerous Cenozoic examples. Russian-Style Formation Evaluation. Bob Harrison (Editor). The London Petrophysical Society and the Geological Society, London, 1995, 244 pp., US$323.50. With the increasing access of Western explorationists to information from the former USSR, many differences in technology have become apparent. This volume is intended to summarize current understanding of the logging methods used in petroleum wells of the USSR (and its former sattelites). Information of possible interest in mineral exploration includes a chapter with extensive stratigraphic sections and maps of many petroleum basins, and a glossary of drilling and logging terms and abbreviations. The Geochemistry of Reservoirs. J.M. Cubitt and W.A. England (Editors). The Geological Society, London, 1995, 321 pp., US$108.00.
Book rwiw.t
case history each from Canada, France, Scotland, Spain and Wales. The International Association of Exploration Geochemists has, since its inception, had a large and active group of members in North America, so the paucity of contributions from that part of the world is particularly surprising. The second omission is the lack of any mention of the current widespread use of glacial sediments, of various types, as sampling media in diamond exploration. Since this type of exploration depends on the retrieval of kimberlite indicator mineral grains from, rather than on chemical analyses of, the samples collected, it may not, perhaps, be considered as geochemical exploration, in the strictest sense, but is obviously a closely related topic. A thorough understanding of the modes of transportation and deposition of glacigenic regoliths is essential for those engaged in diamond exploration; it would, therefore, have been appropriate to have included, in this volume, some discussion of the particular problems they are likely to encounter. Glen Sinclair Toronto
Drift Exploration in the Canadian Cordillera. P.T. Bobrowsky, S.J. Sibbick, J.M. Newell and P.F. Matysek (Editors). British Colombia Ministry of Energy, Mines and Petroleum, Victoria, B.C., 1995, 504 pp., Can.$40.00. Exploration for mineral resources in areas covered by unconsolidated sediments of varying complexity and thickness places special demands on the methods used. Glaciated terrain is known to be a very distinctive field in exploration and within a given glaciated terrain, mountainous areas such as the Canadian Cordillera constitute a separate unit. Canadian geologists have realized that working in mountainous terrain dominated by Quatemary deposits requires a change in exploration strategy. In the foreword the mineral exploration in editors state: “Successful Quatemary-dominated terrain requires an appreciation and understanding of the surficial sediment cover, glacial history, glacial dispersal theory and soil formation, which can assist in the interpretation
of the overburden cover.” For a Quatemary geologist who has worked in exploration in northern Europe (Scandinavia and Finland) for more than twenty years this is nothing new. But to get an exploration geologist with a different kind of background or speciality to appreciate this fact seems to be as difficult in Canada as it has been in Europe. This collection of case histories provides many ideas for geologists working in the glaciated terrain to think about. The volume is a compilation of papers on various aspects of exploration in glaciated areas, mostly from British Columbia. This is an area in which numerous glacial phases have been recognized and where, therefore, patterns of glacial dispersion as well as thickness of till cover and types of moraine deposits vary throughout the whole province. Moreover, the variable topographic relief of this mountainous terrain brings an additional special feature to prospecting. Papers in the volume are grouped thematically, which assists the reader in finding those which are close to his/her speciality. Altogether 25 papers are included in the volume, most of them dealing with Quatemary geological problems and geochemistry. However, the three papers concerning the use of geophysical methods form a useful addition. Topics are diverse, and cover many principles of surficial geology such as recognition of paleo-flow direction, drift potential mapping, methods of drilling as well as glacial dispersal using indicator clasts. Geochemical contributions address various methods of till geochemistry and biogeochemical sampling, lake sediment research, laboratory techniques and new research interests such as partitioning studies. Geophysical papers deal with shallow seismic methods, borehole analysis and resistivity mapping. The papers include an abundance of illustrations, maps, graphical presentations and photos. Therefore the overall style is modem and makes the book easy to read, which is a good thing for a busy reader. However, an improvement in the quality of diagrams would make it even more easier to read. All too often overly sophisticated methods for the interpretation of results are used in these kinds of papers, but in the present case the authors can be congratulated for concentrating only on the essential things needed in every day prospecting. Exploration geologists from the glaciated terrain
Book twiews
of Europe are very familiar with problems discussed in this volume and they have written a huge number of papers on these topics during past twenty years. It seems to me, however, that the authors are not aware of those European publications. This is not only the fault of the authors of this volume, but is a very common problem among scientists today, namely not having time to read what colleagues in other parts of the world have already done. Instead, however, they do have time and money to do and write the same things again and again. Of course every study area has its own distinguishing features that have to be taken into account in the way that has been done in this project, but glaciated terrain also shares many common features irrespective of location. My opinion is, that discussing common problems and distinctive features at congresses, workshops, and seminars with colleagues from other parts of the world would save a lot of money for new research work instead of repeating the same work over and over. The papers included in the volume give a good background to the problems encountered when prospecting in glaciated terrain. They are written in a style that an ordinary prospector can understand. As such it could be recommended to be used as a textbook even in universities, and other schools giving education in exploration. Reijo Salminen Espoo
The following books of specialized interest have been received and are given brief reviews. Geofluids: Origin, Migration and Evolution of Fluids in Sedimentary Basins. J. Parnell (Editor). The Geological Society, London, 1994, 372 pp., US$lO8.00. The migration of water through sedimentary materials is generally recognized as a key phenomenon in diagenesis, transport of metals and petroleum, heat flow, and other processes. Of particular interest among the 21 chapters are those on metamorphic fluids in ore formation (Phillips et al.), origin of saline fluids in sedimentary basins (Hanor), fluid chemistry and hydrology in geothermal and gold
89
depositing systems (Nicholson), role of geopressure zones in MVT genesis (Fowler), fluid-rock interaction in redbeds as related to mineralization (Metcalfe et al.) and recognition of thermal effects of fluid flow in sedimentary basins (Duddy et al.). An Introduction to Mining Seismology. S.J. Gibowicz and A. Kijko. Academic Press, 1994, 399 pp., US$69.95. Disturbances related to mining can cause seismic events with magnitudes exceeding 4. The most severe seismic events are rockbursts, but seismic networks in major mining districts record more than 100 events per year. This book discusses generation, transmission and measurement of seismic events related to mining, and methods of using this data. Volcanism Associated with Extension at Consuming Plate Margins. J.L. Smellie (Editor). The Geological Society, London, 1994, 293 pp., US$lOO.OO. The papers in this book provide evidence that subducting plates are commonly subject to extension, and that arc volcanism is associated with this extension rather than with compressional tectonics. The chemistry and character of the resulting volcanics are documented for numerous Cenozoic examples. Russian-Style Formation Evaluation. Bob Harrison (Editor). The London Petrophysical Society and the Geological Society, London, 1995, 244 pp., US$323.50. With the increasing access of Western explorationists to information from the former USSR, many differences in technology have become apparent. This volume is intended to summarize current understanding of the logging methods used in petroleum wells of the USSR (and its former sattelites). Information of possible interest in mineral exploration includes a chapter with extensive stratigraphic sections and maps of many petroleum basins, and a glossary of drilling and logging terms and abbreviations. The Geochemistry of Reservoirs. J.M. Cubitt and W.A. England (Editors). The Geological Society, London, 1995, 321 pp., US$108.00.