Sedimentology of the southern Bellingshausen Sea

A major trough ('Belgica Trough') eroded by a palaeo-ice stream crosses the continental shelf of the southern Bellingshausen Sea (West Antarctica) and is associated with a trough mouth fan ('Belgica TMF') on the adjacent continental slope. Previous marine geophysical and geological studies investigated the bathymetry and geomorphology of Belgica Trough and Belgica TMF, erosional and depositional processes associated with bedform formation, and the temporal and spatial changes in clay mineral provenance of subglacial and glaciomarine sediments. Here, we present multi-proxy data from sediment cores recovered from the shelf and uppermost slope in the southern Bellingshausen Sea and reconstruct the ice-sheet history since the last glacial maximum (LGM) in this poorly studied area of West Antarctica. We combined new data (physical properties, sedimentary structures, geochemical and grain-size data) with published data (shear strength, clay mineral assemblages) to refine a previous facies classification for the sediments. The multi-proxy approach allowed us to distinguish four main facies types and to assign them to the following depositional settings: 1) subglacial, 2) proximal grounding-line, 3) distal sub-ice shelf/subsea ice, and 4) seasonal open-marine. In the seasonal open-marine facies we found evidence for episodic current-induced winnowing of near-seabed sediments on the middle to outer shelf and at the uppermost slope during the late Holocene. In addition, we obtained data on excess 210Pb activity at three core sites and 44 AMS 14C dates from the acid-insoluble fraction of organic matter (AIO) and calcareous (micro-)fossils, respectively, at 12 sites. These chronological data enabled us to reconstruct, for the first time, the timing of the last advance and retreat of the West Antarctic Ice Sheet (WAIS) and the Antarctic Peninsula Ice Sheet (APIS) in the southern Bellingshausen Sea. We used the down-core variability in sediment provenance inferred from clay mineral changes to identify the most reliable AIO 14C ages for ice-sheet retreat. The palaeo-ice stream advanced through Belgica Trough after ~36.0 corrected 14C ka before present (B.P.). It retreated from the outer shelf at ~25.5 ka B.P., the middle shelf at ~19.8 ka B.P., the inner shelf in Eltanin Bay at ~12.3 ka B.P., and the inner shelf in Ronne Entrance at ~6.3 ka B.P.. The retreat of the WAIS and APIS occurred slowly and stepwise, and may still be in progress. This dynamical ice-sheet behaviour has to be taken into account for the interpretation of recent and the prediction of future mass-balance changes in the study area. The glacial history of the southern Bellingshausen Sea is unique when compared to other regions in West Antarctica, but some open questions regarding its chronology need to be addressed by future work.

Neodymium isotopic record of planktonic foraminifera in sediment core MD81-LC21

A well developed sapropel (S5) was deposited in the eastern Mediterranean during the Last Interglacial (Eemian), 124-119 ka. Freshwater contributions to the basin at this time can be traced using the isotopic composition of Nd in planktonic foraminifera. This enables differentiation between radiogenic sources to the south, under the influence of the African monsoon, and unradiogenic sources to the north, relating to the mid-latitude westerlies. Here we compare new Nd data, from a core in the southeast Aegean Sea, with published data from the Ionian and Levantine Seas. Shifts towards more radiogenic Nd in the lower and middle parts of sapropel S5 are most pronounced in the Ionian Sea record, with epsioln-Nd and d18O G. ruber co-varying more closely here than in the Levantine and Aegean Seas. This is consistent with a freshwater source proximal to the Ionian Sea site, likely indicating a substantial reactivation of rivers flowing northward from the central Saharan watershed. The lack, during S5 deposition, of a noticeable shift towards more unradiogenic Nd in the Aegean record would exclude a large influx of water from the northern borders of the eastern Mediterranean during sapropel deposition. These findings support a scenario whereby the Last Interglacial eastern Mediterranean was influenced strongly by the remote effects of an intensified African monsoon, with more local precipitation in the northern borders contributing relatively little to the sea surface composition.

Japan : production and imports of food : an analysis of the welfare cost of protection /

Cover title.

Canadian feed grain policy /

Bibliography: p. 19-20.

Social Security Act amendments of 1949 : hearings before the Committee on Ways and Means, House of Representatives, Eighty-first Congress, first session, on H.R. 2892, a bill to amend the Social Security Act to enable states to establish more adequate public-welfare programs, and for other purposes, and other bills [and] H.R. 2893, a bill to extend and improve the old-age and survivors insurance system, to add protection against disability, and for other purposes, and other bills.

Considers legislation to extend and improve the Old-Age and Survivors Insurance system, and to add disability protection. Includes H. Rpt. 80-2168, "Social Security Act Amendments, 1948," on H.R. 6777, June 2, 1948 (p. 1096-1158), pt.2.

Development, growth, and state of the atomic energy industry : hearings before the Joint Committee on Atomic Energy, Congress of the United States, Eighty-fifth Congress, first session ... /

Focuses on progress made in private industry.

Air pollution in Charleston, South Carolina.

Bibliography: pages 19-20.

A precipitation climatology for stations in the tropical Pacific basin : effects of ENSO /

"February 1998."

Ohio Circuit court reports. New series.

Title varies: v. 1-18, Ohio Circuit court reports. New series...Cases adjudged in the Circuit courts of Ohio; v. 19-20, Ohio Circuit Court and Appellate court reports. New series...Cases adjudged in the Circuit courts and Courts of appeal of Ohio; v. 21-26, Ohio Appellate and Circuit court reports. New series...Cases adjudged in the courts of appeal and circuit courts of Ohio; v. 27-32, Ohio Courts of appeals reports (cited O.C.A.)...Cases adjusted in the Courts of appeals of Ohio.

Sylloge fungorum omnium hucusque cognitorum /

Additamenta contains additional species for v.3-4. Subsequently, these species are incorporated in the volumes to which they belong according to the systematic classifaction of the entire work, and are indexed in v.12.

Grotte, labyrinthe, fontaines et bassins de Versailles.

This volume has been designated "sixième volume" in the Catalogue, for a collection known under the title of the repository, Cabinet du roi. The engravings were prepared between 1672 and 1689 by various engravers: Le Pautre, Le Clerc, Chauveau, Edelinck, Picart, Baudet, Silvestre, Simonneau and Chatillon. They were issued individually at the outset, collected, and in this instance issued in uniform format. The plates of the Labyrinthe, 15 x 8.5 cm., have been printed on 4 leaves of 9 and 1 leaf of 5.

Piano concerti. [music] : [no. 1-28] /

Cover title.

Bulletin.

"Jubilé du soixante-quinzième anniversaire. Paris et Noyon, 8-10 juillet 1927": v. 76, 1927, p. [305]-389.