Paleomagnetic, geochemical, and isotopic analysis of ...
7730E
773230"
isotope measurements and potassium-argon age determinations. Transport to the islands, helicopter assistance on the islands, and all other logistic support were generously provided by M. P. Rolland, Administrator of the Terres Australes et Antarctiques Françaises. The collections were made with the assistance of Dr. Jacques Nougier, who carried out diverse geological activities simultaneously. This work was supported by National Science Foundation grant GV-32480. References Girod, M., G. Camus, and Y. Vialette. 1971. Sur la presence de tholhiites I l'Ile Saint-Paul (Ocean Indien). Contributions Mineralogy and Petrology, 33: 108-117. Gunn, B. M., C. E. Abranson, J . Nougier, N. D. Watkins, and A. Hajash. 1971. Amsterdam Island, an isolated volcano in the southern Indian Ocean. Contributions Mineralogy and Petrology, 32: 79-92. Watkins, N. D. 1972. Hemispherical contrasts in support for the offset dipole hypothesis: the case for an unequal coaxial dipole pair as the geomagnetic field source. Royal Astronomical Society. Geophysical Journal, 28: 193-212. Watkins, N. D., C. E. Abranson, and A. Hajash. 1972. Geomagnetic secular variation during the Brunhes epoch in the Indian and Atlantic Ocean regions. Royal Astronomical Society. Geophysical Journal, 28: 1-25.
Figure 2. Topographic map of Amsterdam I., with location of sampled igneous bodies. Contours at 100 meter intervals. Note sample numbers 1 to 12 refer to sites of collection made during 1968-1969 season. Numbers 13 to 32 made during January 1972. From each body, at least six separately oriented cores have been taken.
Paleomagnetic, geochemical, and isotopic analysis of rocks from Kerguelen Island, south Indian Ocean N. D. WATKINS Graduate School of Oceanography University of Rhode Island Basaltic rocks were collected from several parts of the Kerguelen archipelago (fig., p. 202) on cruises of the French research ship Galliéni in 1969 and 1970. A total of 128 cores from 28 separate bodies were collected. Paleomagnetic, petrographic, geochemical, potassium-argon, and rubidium-strontium isotope analyses have now been completed in various laboratories and will be published in 1973, together with the results of rubidium-strontium analyses of samples from the Rallier du Baty plutonic body, which forms the southwest peninsula of Kerguelen (Nougier and Lameyre, 1972). The geochemical and isotope data have been obtained by Dr. B. Gunn (University of Montreal), Dr. A. K. Baksi (Queens University, Ontario), and Dr. C. Hedge (U. S. Geological SurFigure 3 (left). Topographic map of St. Paul Island, showing location of sampled igneous bodies. Contours at 10 meter intervals. The coordinates of the center of the island are 38.8° South; 7730 East.
September-October 1972
201
WIVE
49'
490S
Location of samples sites on Kerguelen Islands, Right lower: map of Kerguelen showing location of areas in two topographic maps. Right upper: southern edge of Corbet peninsula showing location of sampled sections on Mt. Chateau and Grande Cascade. Location of French base shown. Left: map of Foch Island showing location of Port Mary section. In both topographic maps contours are at 100 meter intervals.
vey). The plutonic samples have been provided by Dr. J . Nougier (University of Paris). The results have been analysed in the context of the "microcontinental hypothesis," whereby several authors have envisaged the Kerguelen-Gaussberg ridge as a continental fragment remaining after the separation of Gondwanaland. The results do not provide any data consistent with the microcontinent idea, although they do not exclude such a possibility. The collections were made with the generous permission and logistic assistance of M. P. Rolland, Administrator of the Territoire des Terres Australes et Antarctiques Françaises. This work was supported by National Science Foundation grant GV-32480. 202
Reference Nougier, J ., and J. Lameyre. 1972. The problem of the origin of the plutonic rocks of the Kerguelen Islands, Southern Indian Ocean (abstract). EQS (Transactions of the American Geophysical Union), 53(4): 547.
Continuing paleomagnetic and micropaleontological dating of Eltanin deep-sea sedimentary cores N. D. WATKINS and J. P. KENNETT Graduate School of Oceanography University of Rhode Island Sedimentation rates are being determined for all Eltanin deep-sea sedimentary cores, using a combi ANTARCTIC JOURNAL
773230"
isotope measurements and potassium-argon age determinations. Transport to the islands, helicopter assistance on the islands, and all other logistic support were generously provided by M. P. Rolland, Administrator of the Terres Australes et Antarctiques Françaises. The collections were made with the assistance of Dr. Jacques Nougier, who carried out diverse geological activities simultaneously. This work was supported by National Science Foundation grant GV-32480. References Girod, M., G. Camus, and Y. Vialette. 1971. Sur la presence de tholhiites I l'Ile Saint-Paul (Ocean Indien). Contributions Mineralogy and Petrology, 33: 108-117. Gunn, B. M., C. E. Abranson, J . Nougier, N. D. Watkins, and A. Hajash. 1971. Amsterdam Island, an isolated volcano in the southern Indian Ocean. Contributions Mineralogy and Petrology, 32: 79-92. Watkins, N. D. 1972. Hemispherical contrasts in support for the offset dipole hypothesis: the case for an unequal coaxial dipole pair as the geomagnetic field source. Royal Astronomical Society. Geophysical Journal, 28: 193-212. Watkins, N. D., C. E. Abranson, and A. Hajash. 1972. Geomagnetic secular variation during the Brunhes epoch in the Indian and Atlantic Ocean regions. Royal Astronomical Society. Geophysical Journal, 28: 1-25.
Figure 2. Topographic map of Amsterdam I., with location of sampled igneous bodies. Contours at 100 meter intervals. Note sample numbers 1 to 12 refer to sites of collection made during 1968-1969 season. Numbers 13 to 32 made during January 1972. From each body, at least six separately oriented cores have been taken.
Paleomagnetic, geochemical, and isotopic analysis of rocks from Kerguelen Island, south Indian Ocean N. D. WATKINS Graduate School of Oceanography University of Rhode Island Basaltic rocks were collected from several parts of the Kerguelen archipelago (fig., p. 202) on cruises of the French research ship Galliéni in 1969 and 1970. A total of 128 cores from 28 separate bodies were collected. Paleomagnetic, petrographic, geochemical, potassium-argon, and rubidium-strontium isotope analyses have now been completed in various laboratories and will be published in 1973, together with the results of rubidium-strontium analyses of samples from the Rallier du Baty plutonic body, which forms the southwest peninsula of Kerguelen (Nougier and Lameyre, 1972). The geochemical and isotope data have been obtained by Dr. B. Gunn (University of Montreal), Dr. A. K. Baksi (Queens University, Ontario), and Dr. C. Hedge (U. S. Geological SurFigure 3 (left). Topographic map of St. Paul Island, showing location of sampled igneous bodies. Contours at 10 meter intervals. The coordinates of the center of the island are 38.8° South; 7730 East.
September-October 1972
201
WIVE
49'
490S
Location of samples sites on Kerguelen Islands, Right lower: map of Kerguelen showing location of areas in two topographic maps. Right upper: southern edge of Corbet peninsula showing location of sampled sections on Mt. Chateau and Grande Cascade. Location of French base shown. Left: map of Foch Island showing location of Port Mary section. In both topographic maps contours are at 100 meter intervals.
vey). The plutonic samples have been provided by Dr. J . Nougier (University of Paris). The results have been analysed in the context of the "microcontinental hypothesis," whereby several authors have envisaged the Kerguelen-Gaussberg ridge as a continental fragment remaining after the separation of Gondwanaland. The results do not provide any data consistent with the microcontinent idea, although they do not exclude such a possibility. The collections were made with the generous permission and logistic assistance of M. P. Rolland, Administrator of the Territoire des Terres Australes et Antarctiques Françaises. This work was supported by National Science Foundation grant GV-32480. 202
Reference Nougier, J ., and J. Lameyre. 1972. The problem of the origin of the plutonic rocks of the Kerguelen Islands, Southern Indian Ocean (abstract). EQS (Transactions of the American Geophysical Union), 53(4): 547.
Continuing paleomagnetic and micropaleontological dating of Eltanin deep-sea sedimentary cores N. D. WATKINS and J. P. KENNETT Graduate School of Oceanography University of Rhode Island Sedimentation rates are being determined for all Eltanin deep-sea sedimentary cores, using a combi ANTARCTIC JOURNAL
