Marine C reservoir ages for 19th century whales and molluscs from the North Atlantic     

Jan Mangerud  Stein Bondevik  Steinar Gulliksen  Anne Karin Hufthammer  Tore Hister 《Quaternary Science Reviews》2006,25(23-24):3228

In order to compare radiocarbon dates on marine and terrestrial samples the former have to be corrected for a reservoir age. We present reservoir ages from dating 21 whales collected 1860–1901 and recalculating dates of 23 molluscs collected 1857–1926. Most of the whales were caught along the coast of Norway, but one is from France and one from Iceland. We assume the former mainly lived in the North and equatorial Atlantic and in the Norwegian Sea. Whales feed only on pelagic organisms and will provide the reservoir age for the open ocean surface water. However, they travel long distances and will integrate the reservoir ages of the different water masses along their way. Molluscs (dated from Norway, Spitsbergen and Arctic Canada) are stationary and monitor the sea water passing their dwelling site, but some also take up carbon from particulate food or sediment pore water. Coastal water also often contains some continental carbon. We present two different views on how to analyze and interpret the data. Mangerud recommends to use reservoir ages based on a combination of the whale and mollusc dates, i.e. 380±30 and 360±30 yr relative to Intcal04 and British oak, respectively, and a ΔR value of 20±30 for the surface water in the N-Atlantic and Norwegian Sea. Bondevik and Gulliksen maintain that the reservoir age—and ΔR—along the Norwegian coast is latitude dependant, with ΔR-values increasing from −3±22 in the South to 105±24 at Spitsbergen. Whales, reflecting North Atlantic open ocean surface water have lower ΔR (7±11) than most molluscs.  相似文献   

The sedimentary and geochemical record of Neogene-Quaternary water bodies in the Dead Sea Basin - inferences for the regional paleoclimatic history     

Mordechai Stein 《Journal of Paleolimnology》2001,26(3):271-282

Several waterbodies occupied the tectonic depressions along the Dead Sea transform during the NeogeneQuaternary. The earliest of these water bodies was the marine Sedom lagoon, which produced the SedomDead Sea brine. After the disconnection of the Sedom lagoon from the open sea several lakes were developed in the Dead Sea basinJordan Valley. Lake Amora (Samra) that existed from early to late Pleistocene, Lake Lisan (~ 70–15 kyr B.P.), and the Holocene Dead Sea. The lacustrine water bodies in the Dead Sea basin behave as amplifier lakes whose size and depth reflect the changing climatic conditions in the region. Lake level and limnological conditions of Lake Amora are not yet known, nevertheless, the lake probably extended over a large part of the Dead Sea basin-Jordan Valley. Lake Lisan level changed between ~ 330 and ~ 150 meters below sea level (m b.s.l.). Its maximum elevation was reached at ~ 27–23 kyr B.P. during marine isotope stage 2. Its minimum elevation was reached at ~ 47–43 kyr during marine isotope stage 3. Lake Lisan began to recede at ~ 17–15 kyr B.P. and at 12–11 kyr B.P. the postLisan water body declined to its minimum level. During most of the Holocene the lake (paleoDead Sea) stabilized at ~ 400 m b.s.l.The limnological evolution of water bodies in the Dead Sea basin reflects the climatic conditions in the region during the late Pleistocene, which fluctuated between wetter and drier periods. During Lisan time these fluctuations appear to be modulated by the cold and warm cycles, respectively in the northern Hemisphere. This relation is less obvious in the postLisan water body, where the strongest lake drop appears to occur during the Younger Dryas cold event.  相似文献   

Late Neogene evolution of paleoclimate and paleoceanic circulation in the Northern and Southern Hemispheres - A comparison     

Dr. Rüdiger Stein 《International Journal of Earth Sciences》1986,75(1):125-138

Oxygen isotopes and clay minerals, grain size, and accumulation rates of terrigenous (i. e., mainly eolian) sediments from northeast Atlantic DSDP-Sites 141, 366, 397 and 544B and from southwest Pacific DSDP-Sites 588, 590 and 591 were used to assess parallelisms and differences in the evolution of paleoclimate and paleoceanic circulation in the Northern and Southern Hemispheres during the last 7 Ma. Concomitant with the Messinian cooling event, both northwest African and Australian deserts expanded, as defined by increased supply of illite and increased accumulation rates of terrigenous matter. After an early Pliocene phase of more humid climatic conditions in Australia, as well as in northwest Africa, the accumulation rates of terrigenous sediments distinctly increased in the Southwest Pacific at about 4 Ma, whereas the northeast Atlantic Sites were still characterized by low terrigenous sediment supply until 3.2 Ma. Coincident with the build-up of major Arctic ice sheets during the last 3 Ma, increased aridity and enhanced atmospheric and oceanic circulation in the Northern and Southern Hemispheres were inferred from distinct changes in the terrigenous sediment supply and a coarsening of both bulk and terrigenous sediment fractions.  相似文献   

Holocene climate variability and cultural evolution in the Near East from the Dead Sea sedimentary record   总被引：4，自引：2，他引：2  

Claudia Migowski  Mordechai Stein  Sushma Prasad  Jrg F.W. Negendank  Amotz Agnon 《Quaternary Research》2006,66(3):421-431

A comprehensive record of lake level changes in the Dead Sea has been reconstructed using multiple, well dated sediment cores recovered from the Dead Sea shore. Interpreting the lake level changes as monitors of precipitation in the Dead Sea drainage area and the regional eastern Mediterranean palaeoclimate, we document the presence of two major wet phases ( 10–8.6 and  5.6–3.5 cal kyr BP) and multiple abrupt arid events during the Holocene. The arid events in the Holocene Dead Sea appear to coincide with major breaks in the Near East cultural evolution (at  8.6, 8.2, 4.2, 3.5 cal kyr BP). Wetter periods are marked by the enlargement of smaller settlements and growth of farming communities in desert regions, suggesting a parallelism between climate and Near East cultural development.  相似文献   

The fluvial and geomorphic context of Indian Knoll,an Archaic shell midden in West‐Central Kentucky     

Darcy F. Morey  George M. Crothers  Julie K. Stein  James P. Fenton  Nicholas P. Herrmann 《Geoarchaeology》2002,17(6):521-553

Indian Knoll is the largest Archaic shell midden excavated by WPA archaeologists in Kentucky. Situated in a large alluvial valley, the site is not associated with a known river shoal as might be expected, making its fluvial and geomorphic setting of interest. Based on sediment cores and auger samples, undisturbed portions of the site remain despite extensive excavations. In undisturbed portions, a shell‐bearing layer is overlain by a shell‐free midden layer. Profiles of organic matter and calcium carbonate content for both layers are similar to those of other Green River shell middens. New radiocarbon determinations date the shell deposit at 5590–4530 cal yr B.P. Analysis of mussel species collected from the Indian Knoll indicates that shell fishing took place in a swiftly flowing, shallow to moderately deep setting of the main river channel. Overall, the prehistoric river setting adjacent to Indian Knoll was characterized by deeper water on average with variable but finer‐grained substrate compared to other Green River shell midden sites. © 2002 Wiley Periodicals, Inc.  相似文献   

Franchthi Cave and Paralia: Maps,Plans, and Sections,by T. W. Jacobsen and W. R. Farrand,With Contributions by F. A. Cooper and C. J. Vitaliano, 1988 (Excavations at Franhthi Cave,Greece, Fascicle 1), Indiana University Press, 71 Plates,xiv + 33 p., $85.00 (boxed)     

Julie K. Stein 《Geoarchaeology》1991,6(2):192-192

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