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The theory of geomagnetic induction
Book Reviews
112
concept of plate tectonics, which has important implications for so many aspects of earth science. Other innovations during the 1960’s included the study of free oscillations and of the generalisation and limitations of the inverse problem in geophysics. All these topics are well represented. Other topics covered range from the remote and intractable, such as the early history of the earth and the origin of the earth’s magnetic field, to aspects of regional geophysics, and specific but appropriate physical properties of rocks, minerals and metals. In a short review of such a large and excellent volume it is difficult, and no doubt invidious, to select individual articles for comment and commendation, but I think it would be appropriate in this instance to mention the article by the late Paul Gast on the chemical composition of the earth, the moon and chondritic meteorites. In it the work of the past decade, much of it his own, on the isotopic and trace-element composition of crustal and lunar rocks is related to the composition of the earth’s mantle and the moon’s interior and the bulk composition of both bodies derived from the chondrite model. He then goes on to speculate on the implications of his inferred compositions for the early history of the earth. The article is typical of so many in this volume in that one is at once impressed by the great strides which were made during the 1960’s in terms of new techniques, results and ideas, but also by the complexities and plethora of new questions to which they have given rise. In a sense as always, the more we know, the more we realise how much we do not know. Clearly there is a great danger that such a high-level research volume will date rather rapidly as a result of new developments. In this regard it is noteworthy that Bullard, in a note added in proof, refers to the work of Higgins and Kennedy which suggests that the earth’s core may well be stably stratified, making large-scale steady motions in the outer, fluid core impossible. This is helpful because this is one of, if not the, most significant development in this field since 1970. It seems probable that this volume will form an invaluable and authoritative source of references and review articles for researchers and graduate students for several years to come. FJ. VINE (Norwich)
ERRATA
A.T. Price, 1973. The theory of geomagnetic induction. Phys. Earth Planet. Inter., 7(3): 227—233.
Page 232. Second column, the 5th line should read “for example Hermance, 1972 and Jones and Price, 1972). The 25th—29th lines should read: “same order as D. Now if a surface charge of density r is built up on the interface, we have: D D in + 2n r (9) and therefore the current extracted from J to build up r is :“. - . .“.
Page 227. The 14th line of section 1 should read: “of specific problems, but also the mathematical arguments involved in designing mathematical problems”. Page 228. Eq. 1 should read: “E = RJ”. In eq. ~ “curl H” should be replaced by “curl2H”. The second and third lines following eq. 5 should read: “be solved subject to the relevant boundary conditions. Also neglectingD in eq. 3 ..
. “.
Page 230. First column, 5th line, replace “much” by “such”; 14th line, replace “r” by “f’. In eq. 8 “Hi” should be replaced by “Hi”. Page 231. Second column, 7th line from the bottom, “one method” should read “our method”.
—
R.J. Banks, 1973. Data processing and interpretation in geomagnetic deep sounding. Phys. Earth Planet. Inter., 7(3): 339—348. Page 346. Eq. 21 should read:
tg 20m
_AB* +A*B AA* _BB* —
(21)
112
concept of plate tectonics, which has important implications for so many aspects of earth science. Other innovations during the 1960’s included the study of free oscillations and of the generalisation and limitations of the inverse problem in geophysics. All these topics are well represented. Other topics covered range from the remote and intractable, such as the early history of the earth and the origin of the earth’s magnetic field, to aspects of regional geophysics, and specific but appropriate physical properties of rocks, minerals and metals. In a short review of such a large and excellent volume it is difficult, and no doubt invidious, to select individual articles for comment and commendation, but I think it would be appropriate in this instance to mention the article by the late Paul Gast on the chemical composition of the earth, the moon and chondritic meteorites. In it the work of the past decade, much of it his own, on the isotopic and trace-element composition of crustal and lunar rocks is related to the composition of the earth’s mantle and the moon’s interior and the bulk composition of both bodies derived from the chondrite model. He then goes on to speculate on the implications of his inferred compositions for the early history of the earth. The article is typical of so many in this volume in that one is at once impressed by the great strides which were made during the 1960’s in terms of new techniques, results and ideas, but also by the complexities and plethora of new questions to which they have given rise. In a sense as always, the more we know, the more we realise how much we do not know. Clearly there is a great danger that such a high-level research volume will date rather rapidly as a result of new developments. In this regard it is noteworthy that Bullard, in a note added in proof, refers to the work of Higgins and Kennedy which suggests that the earth’s core may well be stably stratified, making large-scale steady motions in the outer, fluid core impossible. This is helpful because this is one of, if not the, most significant development in this field since 1970. It seems probable that this volume will form an invaluable and authoritative source of references and review articles for researchers and graduate students for several years to come. FJ. VINE (Norwich)
ERRATA
A.T. Price, 1973. The theory of geomagnetic induction. Phys. Earth Planet. Inter., 7(3): 227—233.
Page 232. Second column, the 5th line should read “for example Hermance, 1972 and Jones and Price, 1972). The 25th—29th lines should read: “same order as D. Now if a surface charge of density r is built up on the interface, we have: D D in + 2n r (9) and therefore the current extracted from J to build up r is :“. - . .“.
Page 227. The 14th line of section 1 should read: “of specific problems, but also the mathematical arguments involved in designing mathematical problems”. Page 228. Eq. 1 should read: “E = RJ”. In eq. ~ “curl H” should be replaced by “curl2H”. The second and third lines following eq. 5 should read: “be solved subject to the relevant boundary conditions. Also neglectingD in eq. 3 ..
. “.
Page 230. First column, 5th line, replace “much” by “such”; 14th line, replace “r” by “f’. In eq. 8 “Hi” should be replaced by “Hi”. Page 231. Second column, 7th line from the bottom, “one method” should read “our method”.
—
R.J. Banks, 1973. Data processing and interpretation in geomagnetic deep sounding. Phys. Earth Planet. Inter., 7(3): 339—348. Page 346. Eq. 21 should read:
tg 20m
_AB* +A*B AA* _BB* —
(21)