Late Quaternary sedimentation on the Eastern Walvis Ridge, SE Atlantic (HPC 532 and four piston...
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1022 D. Submarine Geology and Geophysics OIR 11985732(12) Pacific Basin. Geol. Surv. Japan Cruise Rept, 20:193-197. Clay mineral analyses performed on 65 selected samples from 3 cores reveal the presence of smectite, illite, chlorite, and kaolinite together with non-clay minerals such as quartz, feldspar, calcite, and clinoptilolite. The abundance of smectite in Tertiary sediments is attributed to volcanic activity, its decrease in younger sediments appears to result from dilution by wind and current-borne detrital clay minerals derived from weathering, glaciation, sur- face runoff and wind-induced erosion of continental land masses. Nat. Sci. Lab., Toyo Univ., 5-28-20, Hakusan, Bunkyo-ku, Tokyo 112, Japan. (hbf) 85:7108 Diester-Haass, Liselotte, 1985. Late Quaternary sedgtmentatlon on the Eastern Walvis Ridge, SE Atlantic (HPC 532 and four piston cores). Mar. Geol., 65(1-2): 145-189. Core samples classified as nannofossil foraminifer ooze and foraminifer nannofossil ooze collected on the Walvis Ridge Terrace in an area bordering a very arid section of SW Africa represent Late Quaternary oxygen isotope stages 1-6. Overall sediment accu- mulation varied with location with highest rates near the trough center. Calcium carbonate dissolution was shown to reach maxima at warm/cold stage boundaries and minima during transitions from cold to warm intervals. Upwelling intensity was reflected by varying amounts of biogenic opal and was much reduced during glacial intervals. The climate appears to have remained arid throughout the time interval investigated. Geogr. Inst., Abt. Geol., Univ. Mann- heim, Schloss, Postfach 2428, D-6800 Mannheim, FRG. (hbf) 85:7109 Farrow, G.E. and G.P. Durant, 1985. Carbonate-- basaltic sediments from Cobb Seamount, north- east Pacific: zonation, bioerosion and petrology. Mar. Geol., 65(1-2):73-102. Scoop samples and observations obtained with the submersible Pisces IV at depths from -30 to -700 m at precisely determined locations on the seamount reveal successive faunal zones: echinoid-bivalve- bryozoan from -30 to -90 m, crinoid-brachiopod from -90 to -180 m, coral-brachiopod-ophiuroid from -180 to -500 m, and hydrocoral-crinoid- gorgonian-ophiuroid from -500 to -700 m. Faunal distributions, petrography and the geologic history of the seamount from its eruption at about 1.5 Ma to the present are summarized. Britoil p.l.c., 150 St. Vincent St., Glasgow G2 5L J, Scotland. (hbf) 85:7110 Nishimura, Akira, 1984. VII. Deep-sea sediments in the GHS0-5 area in the northern vicinity of the Magellan Trough. Geol. Surv. Japan Cruise Rept. 20:67-89. Sediment sample, paleontologic, and paleomagnetic data suggest that Eocene siliceous fossil-rich clays were deposited below the CCD in an equatorial high-productivity province. During the Oligocene and Miocene northwestward plate motion removed the study area from the high productivity province. A major hiatus separates these sediments from the Late Pliocene pelagic clays and more recent siliceous fossil-rich clays. A summary is provided of features related to the manganese nodules found in the cores, the great bulk of which occur in Matuyama Re- versed Epoch pelagic clay. Geol. Surv. of Japan, Ibaraki-ken, Japan. (hbf) 85:7111 RullkOtter, Jtirgen and P.K. Mukhopadhyay, 1984. Jurassic and Mid-Cretaceous carbonaceous clay- stones in the western (DSDP Leg 76) and eastern (DSDP Leg 79) North Atlantic. Org. Geochem., 6: 761-767. Deep-sea drilling recovered carbonaceous claystones of Middle-Cretaceous and Mid-Late Jurassic age. Although there are differences in the sedimento- logical and organic geochemical characteristics of these sediments, preservation of the organic matter in both cases appears to be controlled by the intensity of the terrigenous organic matter supply, downslope transport events and local oxygen deple- tion. Inst. of Petrol. and Organic Geochem., KFA Julich GmbH, P.O. Box 1913, D-5170 Julich 1, FRG. 85:7112 Suczek, C.A. and R.V. Ingersoll, 1985. Petrology and provenance of Cenozoic sand from the Indus Cone and the Arabian Basin, DSDP Sites 221, 222, and 224. J. sedim. Petrology, 55(3):340-346. The closing of the remnant ocean basin between India and Asia has produced the uplifted gneissic. sedimentary, and metasedimentary terrane of the western Himalayas. Sediment derived from this source is presently being deposited in the subma- rine-fan and basin-plain complex of the Indus Cone and Arabian Abyssal Plain. Sands resemble those of the Bengal and Nicobar fans, which were also derived from the Himalayas. These plus other sands derived from collision orogenic belts have a dis- tinctive signature: P/F close to 0.66; Lv/L low, 0. l0 or less; and Q dominant, with F and L subequal. Dept. of Geol., Western Washington Univ., Belling- ham, WA 98225, USA.
Transcript of Late Quaternary sedimentation on the Eastern Walvis Ridge, SE Atlantic (HPC 532 and four piston...
1022 D. Submarine Geology and Geophysics OIR 11985732 (12)
Pacific Basin. Geol. Surv. Japan Cruise Rept, 20:193-197.
Clay mineral analyses performed on 65 selected samples from 3 cores reveal the presence of smectite, illite, chlorite, and kaolinite together with non-clay minerals such as quartz, feldspar, calcite, and clinoptilolite. The abundance of smectite in Tertiary sediments is attributed to volcanic activity, its decrease in younger sediments appears to result from dilution by wind and current-borne detrital clay minerals derived from weathering, glaciation, sur- face runoff and wind-induced erosion of continental land masses. Nat. Sci. Lab., Toyo Univ., 5-28-20, Hakusan, Bunkyo-ku, Tokyo 112, Japan. (hbf)
85:7108 Diester-Haass, Liselotte, 1985. Late Quaternary
sedgtmentatlon on the Eastern Walvis Ridge, SE Atlantic (HPC 532 and four piston cores). Mar. Geol., 65(1-2): 145-189.
Core samples classified as nannofossil foraminifer ooze and foraminifer nannofossil ooze collected on the Walvis Ridge Terrace in an area bordering a very arid section of SW Africa represent Late Quaternary oxygen isotope stages 1-6. Overall sediment accu- mulation varied with location with highest rates near the trough center. Calcium carbonate dissolution was shown to reach maxima at warm/cold stage boundaries and minima during transitions from cold to warm intervals. Upwelling intensity was reflected by varying amounts of biogenic opal and was much reduced during glacial intervals. The climate appears to have remained arid throughout the time interval investigated. Geogr. Inst., Abt. Geol., Univ. Mann- heim, Schloss, Postfach 2428, D-6800 Mannheim, FRG. (hbf)
85:7109 Farrow, G.E. and G.P. Durant, 1985. Carbonate--
basaltic sediments from Cobb Seamount, north- east Pacific: zonation, bioerosion and petrology. Mar. Geol., 65(1-2):73-102.
Scoop samples and observations obtained with the submersible Pisces I V at depths from -30 to -700 m at precisely determined locations on the seamount reveal successive faunal zones: echinoid-bivalve- bryozoan from -30 to -90 m, crinoid-brachiopod from -90 to -180 m, coral-brachiopod-ophiuroid from -180 to -500 m, and hydrocoral-crinoid- gorgonian-ophiuroid from -500 to -700 m. Faunal distributions, petrography and the geologic history of the seamount from its eruption at about 1.5 Ma to the present are summarized. Britoil p.l.c., 150 St. Vincent St., Glasgow G2 5L J, Scotland. (hbf)
85:7110 Nishimura, Akira, 1984. VII. Deep-sea sediments in
the GHS0-5 area in the northern vicinity of the Magellan Trough. Geol. Surv. Japan Cruise Rept. 20:67-89.
Sediment sample, paleontologic, and paleomagnetic data suggest that Eocene siliceous fossil-rich clays were deposited below the CCD in an equatorial high-productivity province. During the Oligocene and Miocene northwestward plate motion removed the study area from the high productivity province. A major hiatus separates these sediments from the Late Pliocene pelagic clays and more recent siliceous fossil-rich clays. A summary is provided of features related to the manganese nodules found in the cores, the great bulk of which occur in Matuyama Re- versed Epoch pelagic clay. Geol. Surv. of Japan, Ibaraki-ken, Japan. (hbf)
85:7111 RullkOtter, Jtirgen and P.K. Mukhopadhyay, 1984.
Jurassic and Mid-Cretaceous carbonaceous clay- stones in the western (DSDP Leg 76) and eastern (DSDP Leg 79) North Atlantic. Org. Geochem., 6: 761-767.
Deep-sea drilling recovered carbonaceous claystones of Middle-Cretaceous and Mid-Late Jurassic age. Although there are differences in the sedimento- logical and organic geochemical characteristics of these sediments, preservation of the organic matter in both cases appears to be controlled by the intensity of the terrigenous organic matter supply, downslope transport events and local oxygen deple- tion. Inst. of Petrol. and Organic Geochem., KFA Julich GmbH, P.O. Box 1913, D-5170 Julich 1, FRG.
85:7112 Suczek, C.A. and R.V. Ingersoll, 1985. Petrology and
provenance of Cenozoic sand from the Indus Cone and the Arabian Basin, DSDP Sites 221, 222, and 224. J. sedim. Petrology, 55(3):340-346.
The closing of the remnant ocean basin between India and Asia has produced the uplifted gneissic. sedimentary, and metasedimentary terrane of the western Himalayas. Sediment derived from this source is presently being deposited in the subma- rine-fan and basin-plain complex of the Indus Cone and Arabian Abyssal Plain. Sands resemble those of the Bengal and Nicobar fans, which were also derived from the Himalayas. These plus other sands derived from collision orogenic belts have a dis- tinctive signature: P / F close to 0.66; Lv/L low, 0. l0 or less; and Q dominant, with F and L subequal. Dept. of Geol., Western Washington Univ., Belling- ham, WA 98225, USA.
