1
228 D. Submarine Geology and Geophysics OLR(1986) 33 (3) and was dominated by Epistominella exigua, Uvigerina auberiana, Planulina ariminensis and Tri- farina bradyi. The deeper assemblage (2400-2800 m) was dominated by Eponides bradyi, Eplstominella exigua and Bolivina pseudoplicata. The two assem- blages are confined to the North Atlantic Deep Water and the Antarctic Bottom Water, respectively. Seventy-two species are presented in a systematic catalogue. Dept. of Geol., Univ. of Stockholm, S-106 91 Stockholm, Sweden. 86:1577 Mead, G.A., 1985. Recent benthic Foraminifera in the Polar Front region of the southwest Atlantic. Micropaleontology, 31(3):221-248. Recent benthic Foraminifera were studied in 62 trigger-core tops from the Maurice Ewing Bank and the Islas Orcadas Rise in the Subantarctic-Antarctic region of the southwest Atlantic. Depths of samples ranged 1493-3464 m. Twenty-seven species and 10 'species groups' of calcareous benthic Foraminifera are identified and described here. Most forms are well known from the world's oceans. Scripps Inst. of Oceanogr., La Jolla, CA 92093, USA. D200. Gravity, geodesy, magnetism 86:1578 Bloemendal, J., C.E. Barton and C. Radhakrish- namurthy, 1985. Correlation between Rayleigh loop. and ~e,pm~y-depeudeut and quadrature ~,e~mity: awuemion to masueee p~aom- etry of rocks. J. geophys. Re.s, 90(B10):8789- 8792. Grad. Sch. of Oceanogr., Univ. of Rhode Island, Narragansett, RI 02881, USA. 86:1579 Hood, R.D., D.V. Kent, A.N. Shor and F.R. HaLl, 1985. The magnetic fabric of sadidal deep-sea In the HEBBLE area (Nova Scotian mntimmtal rise). Mar. Geol., 66(I-4):149-167. Measurements of the anisotropy of magnetic sus- ceptibility were made of 125 samples from 4 box cores to relate the fabric of the surficial sediments to existing depositional conditions. Within the upper 1.5 cm of sediment, the primary fabric, which was apparently produced by gravitational settling of particles from a fluid influenced by bottom currents, was retained; whereas below 2.5 cm a secondary fabric resulted from mixing by burrowing organisms. Although it was difficult to obtain the km~ direction for the weakly anisotropic samples the most com- mon orientation was along-slope paralleling mean bottom current trends; there was also, however, a grouping of kmax axes normal to that direction, perhaps due to the variability of depositional conditions. Lamont-Doberty Geol. Observ., Pali- sades, NY 10964, USA. (hbf) 86:1580 Ueda, Yoshi, Takashi Tozaki and Toshiro Kaneko, 1985. Geomagnetic anomalies around the Zenisu Ridge and the Suraga Trough and their tectonic implications. Rept hydrogr. Res, Tokyo, 20:83- 108. (In Japanese, English abstract.) Geodesy and Geophys. Div., Maritime Safety Agency, Tokyo, Japan. D240. Local or regional tectonics 86:1581 Cadet, J.-P. et al., 1985. From Japan Trench to Koril Trench: prdimim~ results of the Fre~h-&q3- anese oceanographic survey Kaiko (Leg HI). C. r. Acad. Sci~ Paris, (S6r. II)301(5):287-296. (In French, English abstract.) New data are provided on the Japan and Kuril trenches and their junction where a left-lateral strike-slip fault offsets the inner wall. The Kuril Trench is a wide, flat plain paralleling oceanic magnetic anomalies. To the south the Kashima Seamount entering the subduction zone has been cut by relatively new, normal faults in the oceanic crust. To the north the gravity slides filling the trench, together with oceanic crust and sediments, are being subducted. Lab. de Geol. dynam., Dept. des Sci. de la Terre, UA CNRS, No. 724, Univ. d'Orleans, 45046 Orleans Cedex, France. (hbf) 86:1582 Cannat, Mathilde and Francoise Boudier, 1985. Stmeamd s t ~ of ~ ~ ttm~ in the Kiamath Mountains, northera Califorala: impli. cations for aeeretion geometry. Tectonics, 4(5): 435-452. The kinematics of the basal intra-oceanic thrust of the ultramafic bodies of the Klamath Mountains are deduced from microstructural and mineral pre- ferred-orientation studies. When corrected for pos- sible post-thrnsting rotations, these kinematics are thought to reflect the paleoconvergence geometry of the Pacific Plate relative to the North American continent at the time of intra-oceanic thrusting. Results are integrated in a plate tectonics recon- struction, and a model of continuous NE-SW convergence for Mesozoic times is proposed. Lab. de Tectonophys., Univ. de Nantes, France.

The magnetic fabric of surficial deep-sea sediments in the HEBBLE area (Nova Scotian continental rise)

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228 D. Submarine Geology and Geophysics OLR (1986) 33 (3)

and was dominated by Epistominella exigua, Uvigerina auberiana, Planulina ariminensis and Tri- farina bradyi. The deeper assemblage (2400-2800 m) was dominated by Eponides bradyi, Eplstominella exigua and Bolivina pseudoplicata. The two assem- blages are confined to the North Atlantic Deep Water and the Antarctic Bottom Water, respectively. Seventy-two species are presented in a systematic catalogue. Dept. of Geol., Univ. of Stockholm, S-106 91 Stockholm, Sweden.

86:1577 Mead, G.A., 1985. Recent benthic Foraminifera in

the Polar Front region of the southwest Atlantic. Micropaleontology, 31(3):221-248.

Recent benthic Foraminifera were studied in 62 trigger-core tops from the Maurice Ewing Bank and the Islas Orcadas Rise in the Subantarctic-Antarctic region of the southwest Atlantic. Depths of samples ranged 1493-3464 m. Twenty-seven species and 10 'species groups' of calcareous benthic Foraminifera are identified and described here. Most forms are well known from the world's oceans. Scripps Inst. of Oceanogr., La Jolla, CA 92093, USA.

D200. Gravity, geodesy, magnetism

86:1578 Bloemendal, J., C.E. Barton and C. Radhakrish-

namurthy, 1985. Correlation between Rayleigh loop. and ~e,pm~y-depeudeut and quadrature ~ , e ~ m i t y : awuemion to masueee p~aom- etry of rocks. J. geophys. Re.s, 90(B10):8789- 8792. Grad. Sch. of Oceanogr., Univ. of Rhode Island, Narragansett, RI 02881, USA.

86:1579 Hood, R.D., D.V. Kent, A.N. Shor and F.R. HaLl,

1985. The magnetic fabric of sadidal deep-sea In the HEBBLE area (Nova Scotian

mntimmtal rise). Mar. Geol., 66(I-4):149-167.

Measurements of the anisotropy of magnetic sus- ceptibility were made of 125 samples from 4 box cores to relate the fabric of the surficial sediments to existing depositional conditions. Within the upper 1.5 cm of sediment, the primary fabric, which was apparently produced by gravitational settling of particles from a fluid influenced by bottom currents, was retained; whereas below 2.5 cm a secondary fabric resulted from mixing by burrowing organisms. Although it was difficult to obtain the km~ direction for the weakly anisotropic samples the most com- mon orientation was along-slope paralleling mean bottom current trends; there was also, however, a

grouping of kma x a x e s normal to that direction, perhaps due to the variability of depositional conditions. Lamont-Doberty Geol. Observ., Pali- sades, NY 10964, USA. (hbf)

86:1580 Ueda, Yoshi, Takashi Tozaki and Toshiro Kaneko,

1985. Geomagnetic anomalies around the Zenisu Ridge and the Suraga Trough and their tectonic implications. Rept hydrogr. Res, Tokyo, 20:83- 108. (In Japanese, English abstract.) Geodesy and Geophys. Div., Maritime Safety Agency, Tokyo, Japan.

D240. Local or regional tectonics

86:1581 Cadet, J.-P. et al., 1985. From Japan Trench to Koril

Trench: prdimim~ results of the Fre~h-&q3- anese oceanographic survey Kaiko (Leg HI). C. r. Acad. Sci~ Paris, (S6r. II)301(5):287-296. (In French, English abstract.)

New data are provided on the Japan and Kuril trenches and their junction where a left-lateral strike-slip fault offsets the inner wall. The Kuril Trench is a wide, flat plain paralleling oceanic magnetic anomalies. To the south the Kashima Seamount entering the subduction zone has been cut by relatively new, normal faults in the oceanic crust. To the north the gravity slides filling the trench, together with oceanic crust and sediments, are being subducted. Lab. de Geol. dynam., Dept. des Sci. de la Terre, UA CNRS, No. 724, Univ. d'Orleans, 45046 Orleans Cedex, France. (hbf)

86:1582 Cannat, Mathilde and Francoise Boudier, 1985.

Stmeamd s t ~ of ~ ~ t t m ~ in the Kiamath Mountains, northera Califorala: impli. cations for aeeretion geometry. Tectonics, 4(5): 435-452.

The kinematics of the basal intra-oceanic thrust of the ultramafic bodies of the Klamath Mountains are deduced from microstructural and mineral pre- ferred-orientation studies. When corrected for pos- sible post-thrnsting rotations, these kinematics are thought to reflect the paleoconvergence geometry of the Pacific Plate relative to the North American continent at the time of intra-oceanic thrusting. Results are integrated in a plate tectonics recon- struction, and a model of continuous NE-SW convergence for Mesozoic times is proposed. Lab. de Tectonophys., Univ. de Nantes, France.