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The Alaskan shelf, hydrographic, sedimentary and geochemical environment
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The Alaskan Shelf, Hydrographic, Sedimentary and Geochemical Environment. G.D. Sharma. Springer, Berlin, 1979, 498 pp. (with 345 illustr.), cloth DM 59.00, approx. U.S. $ 23.50. G.D. Sharma states in the Preface of "The Alaskan Shelf" that his purpose was to interrelate meteorologic, hydrographic, sedimentologic and geochemical parameters to define specific environments on the Alaskan Shelf, and thereby elucidate sedimentary processes and pathways of elemental migration. The first twelve chapters describe the geology, bathymetry, hydrography and sediments in 10 different shelf areas along the Alaskan coast from southeastern Alaska to the Beaufort Sea. A chapter is devoted to each of these regions, and typically contains figures of bathymetry, surface-water temperature and salinity, grain-size distributions, suspended sediment in surface-waters from sample analyses and satellite imagery, and chemical composition of surface sediments, including: total organic carbon, most o f the major elements, titanium, strontium, barium, cobalt, chromium, nickel, copper, manganese and zinc. Some regions were studied in more detail than others, and consequently are described more extensively. The final two chapters o f the b o o k discuss textural and geochemical evolution of the shelf sediment (Ch.13) and a factor analysis of the data (Ch.14). "The Alaskan Shelf" provides useful quantitative data on shelf sediments that will be of particular interest to individuals involved with environmental research or management in Alaskan waters. The b o o k has some shortcomings, however, that will limit its usefulness to marine geologists working outside Alaska. Data are presented in c o n t o u r maps and rarely in tables, thereby preventing others from interpreting the data in new ways. Data interpretation in "The Alaskan Shelf" is quite basic and thus provides little new insight into shelf sedimentary processes. No seismic reflection profiles are presented in conjunction with the sediment data, and finally, references cited in each chapter are sparse and almost entirely pre-1975. There are a few typographical errors, the most serious being a mix-up in C h . l l and 12 in the Table of Contents. Almost all the figures of satellite imagery were smeared, as were some pages of text. The bathymetric charts of the Beaufort Sea (pp.420--423) are illegible. G.D. Sharma obviously p u t a lot of work into "The Alaskan Shelf", and it is an important first step towards achieving his stated goal. THOMAS C. JOHNSON (Duluth, Minn.)
Underwater Minerals. D.S. Cronan. Academic Press, London, 1980, xv ÷ 363 pp., U.S. $ 57.50. This b o o k treats three classes of submarine deposits: (1) those which have been or are currently being exploited (placers, offshore sand and gravel); (2) those which may be exploited in the future (manganese nodules, hydrothermal deposits, and deposits o f phosphate); and (3) minerals of more academic interest which form on the seafloor. The author has attempted to satisfy the need for an up-to-date t e x t b o o k and to pull together the diverse literature on the subject. The readership aimed at includes undergraduate and
The Alaskan Shelf, Hydrographic, Sedimentary and Geochemical Environment. G.D. Sharma. Springer, Berlin, 1979, 498 pp. (with 345 illustr.), cloth DM 59.00, approx. U.S. $ 23.50. G.D. Sharma states in the Preface of "The Alaskan Shelf" that his purpose was to interrelate meteorologic, hydrographic, sedimentologic and geochemical parameters to define specific environments on the Alaskan Shelf, and thereby elucidate sedimentary processes and pathways of elemental migration. The first twelve chapters describe the geology, bathymetry, hydrography and sediments in 10 different shelf areas along the Alaskan coast from southeastern Alaska to the Beaufort Sea. A chapter is devoted to each of these regions, and typically contains figures of bathymetry, surface-water temperature and salinity, grain-size distributions, suspended sediment in surface-waters from sample analyses and satellite imagery, and chemical composition of surface sediments, including: total organic carbon, most o f the major elements, titanium, strontium, barium, cobalt, chromium, nickel, copper, manganese and zinc. Some regions were studied in more detail than others, and consequently are described more extensively. The final two chapters o f the b o o k discuss textural and geochemical evolution of the shelf sediment (Ch.13) and a factor analysis of the data (Ch.14). "The Alaskan Shelf" provides useful quantitative data on shelf sediments that will be of particular interest to individuals involved with environmental research or management in Alaskan waters. The b o o k has some shortcomings, however, that will limit its usefulness to marine geologists working outside Alaska. Data are presented in c o n t o u r maps and rarely in tables, thereby preventing others from interpreting the data in new ways. Data interpretation in "The Alaskan Shelf" is quite basic and thus provides little new insight into shelf sedimentary processes. No seismic reflection profiles are presented in conjunction with the sediment data, and finally, references cited in each chapter are sparse and almost entirely pre-1975. There are a few typographical errors, the most serious being a mix-up in C h . l l and 12 in the Table of Contents. Almost all the figures of satellite imagery were smeared, as were some pages of text. The bathymetric charts of the Beaufort Sea (pp.420--423) are illegible. G.D. Sharma obviously p u t a lot of work into "The Alaskan Shelf", and it is an important first step towards achieving his stated goal. THOMAS C. JOHNSON (Duluth, Minn.)
Underwater Minerals. D.S. Cronan. Academic Press, London, 1980, xv ÷ 363 pp., U.S. $ 57.50. This b o o k treats three classes of submarine deposits: (1) those which have been or are currently being exploited (placers, offshore sand and gravel); (2) those which may be exploited in the future (manganese nodules, hydrothermal deposits, and deposits o f phosphate); and (3) minerals of more academic interest which form on the seafloor. The author has attempted to satisfy the need for an up-to-date t e x t b o o k and to pull together the diverse literature on the subject. The readership aimed at includes undergraduate and