973 resultados para Ross, Francis E.,


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High-resolution geophysical and sediment core data are used to investigate the pattern and dynamics of former ice flow in Kvitøya Trough, northwestern Barents Sea. A new swath-bathymetric dataset identifies three types of submarine landform in the study area (streamlined landforms, meltwater channels and cavities, iceberg scours). Subglacially produced streamlined landforms provide a record of ice flow through Kvitøya Trough during the last glaciation. Flow directions are inferred from the orientations of streamlined landforms (drumlins, crag-and-tail features). Ice flowed northward for at least 135 km from an ice divide at the southern end of Kvitøya Trough. A large channel-cavity system incised into bedrock in the southern trough indicates that subglacial meltwater was present at the former ice-sheet base. Modest landform elongation ratios and a lack of mega-scale glacial lineations suggest that, although ice in Kvitøya Trough was melting at the bed and flowed faster than the likely thin and cold-based ice on adjacent banks, a major ice stream probably did not occupy the trough. Retreat was relatively rapid after 14-13.5 14C kyr B.P. and probably progressed via ice sheet-bed decoupling in response to rising sea level. There is little evidence for still stands during ice retreat or of ice-proximal deglacial sediments. Relict iceberg scours in present-day water depths of more than 350 m in the northern trough indicate that calving was an important mass loss mechanism during retreat.

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A suite of petropysical measurements - velocity versus pressure, bulk density, porosity, matrix density, and magnetic susceptibility -was undertaken on 63 core plugs from CRP-2A. These data are used to calibrate neutron, resistivity, and magnetic susceptibility well logs. Agreement between core-plug magnetic susceptibility measurements and both well-log and whole-core data is excellent. Comparison of core-plug bulk densities with continious well-log density records shows very good agreement. Core-plug measurements of matrix density permit conversion of the well-log and whole-core density records to porosity. Sands and muds exhibit similar downhole compaction patterns, and both patterns are consistent with 250 ± 150 m of exhumation. Pervasive cementation, particularly in the lower half of the core, has affected many CRP-2A petrophysical parameters: (1) fractional porosities are reduced by about 0.05 - 0.10 in the lower part of the hole; (2) velocity and porosity rebound are much smaller than is usually observed for unconsolidated sediments with burial depths similar to CRP-2A; (3) velocities are unusually insensitive to pressure, suggesting that any exhumation-induced microcracks have been scaled subsequently; (4) the velocity/porosity relationship lacks the characteristic signature of exhumation-induced microcracks; (5) the velocity/porosity relationship changes with depth, indicating downhole increase in consolidation; (6) Vp/Vs ratios of the highest-porosity sediments are unusually low, implying enhancement of framework stiffness.

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Marine diatoms are the primary biostratigraphical and paleoenvironmental tool for interpreting the upper Palaeogene and lower Neogene strata recovered during the second drilling season of the Cape Roberts Project at site CRP-2 in the western Ross Sea, Antarctica. Silicoflagellates, ebridians, and a chrysophyte cyst provide supporting biostratigraphical information. More than 100 dominantly planktic diatom taxa are recognised. Of these, more than 30 are treated informally, pending SEM examination and formal description. Many other taxa are noted only to generic level. Lower Oligocene (c. 31 Ma) through lower Miocene (c. 18.5 Ma) diatoms occur from 28 mbsf down to 565 mbsf. Below this level, to the bottom of the hole at 624.15 mbsf, diatom assemblages are poorly-preserved and many samples are barren. A biostratigraphic zonal framework, consisting of ten diatom zones, is proposed for the Antarctic continental shelf. Ages inferred from the diatom biostratigraphy correspond well with geochronological data from argon dating of volcanic materials and strontium dating of calcareous macrofossils, as well as nannofossil biochronological datums. The biochronostratigraphical record from CRP-2/2A provides an important record of diatom events and mid-Cenozoic environmental changes in the Antarctic neritic zone.

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A faunal comprising 18 foraminiferal taxa wa recovered from a suite of 52 core samples from lower Miocene sandstone, claystone and diamictite in the CRP-1 drillhole, Cape Roberts, Antarctica. The fauna is characterised by low foraminiferal abundance and diversity, the absence of planktics, and typically, the presence of Cribroelphidium sp. and/or Melonis spp. These factors indicate deposition in an inner shelf or nearshore environment. Many of the foraminifers found in CRP-1 also occure in the upper Oligocene-Miocene sequences in CIROS-1 and DSDP-270, but the fauna provides no precise indication of age. Typical and distinctive species from CRP-1 are illustrated with SEM photomicrographs.

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F available only in microfiche

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Announcement of success of the Salk polio vaccine following test trials at the University of Michigan

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Back Row: Dick Lindenfeld, Frank Gusich, Robert Rosema, Mike Smith, William Ross, Dennis Connell, Scott Hulke, Tom Alexander, ?, Jim Schmitz

8th Row: Ed Woolley, Tom Huiskens, Paul Seymour, Reggie McKenzie, Donald Shaw, Jim Brandstatter, Mike Oldham, Fred Grambau, Tom Beckman

7th Row: Guy Murdock, Fritz Seyferth, Bruce Elliott, Allen Carpenter, Mike Keller, Dave Zuccarelli, Dana Coin, Preston Henry, George Mans

6th Row: Michael Taylor, Tom Darden, Tom Nieman, John Wolff, Gerald Dutcher, Ed Baldwin, Glen Doughty, William Taylor, Louie Lee*

5th Row: Bill Berutti, Thomas Takach, Lance Scheffler, Dick McCoy, Pete Newell, Dan Parks, Bill Harris, Greg Harrison, Jim Young*

4th Row: George Zuganelis, Paul Staroba, Jim Betts, Jack Harpring, Marty Huff, Ed Moore, Don Moorehead,Tim Killian, Frank Maloney*,

3rd Row: Henry Hill, Robert Ritley, Joe Lukz, Timothy Wadhams, Richard Brown, Eric Federico, Mark Werner, Dan Dierdorf, Robert White, Chuck Stobart*

2nd Row: Jerry Hanlon*, Dick Hunter*, Gary Moeller*, Larry Smith* Morris Abrahams, Jerry Imsland, Joe Jones, Barry Pierson, Richard Caldarazzo, Al Francis, Peter Sarantos, Werner Hall, Mike Hankwitz, coach Bo Schembechler

Front Row: Phil Seymour, Frank Titas, Bob Baumgartner, Tom Curtis, captain Jim Mandich, Brian Healey, John Gabler, Garvie Craw, Cecil Pryor

* = assistant coaches

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Pittsfield Township (Mich.) residences. Publication information: Chicago, Ill. : Everts & Stewart, 1874.

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