Climate Inferred from Geology and Archaeology

Author(s):  
K. O. Emery ◽  
David Neev

Early climatic interpretations for the Lisan and later formations (Late Pleistocene and Holocene—Neev and Emery, 1967, figs. 16, 17) were supported and updated by information from additional coreholes. Although most new and old coreholes bottomed at relatively shallow depths, 20 to 30 m, four of them reached greater depths, 74, 80, 161, and 285 m beneath the 1960 floor of the Dead Sea south basin. The sequences consist of alternating layers of marl and rocksalt. Most marls were deposited from dilute brine during high lake levels and contain alternating laminae of chemical deposits of white aragonite, gray gypsum, and fine-grained detritus consisting of yellowish, brown, green, or dark gray carbonates, quartz, and clay. The detrital fraction is coarser and more dominant toward the deltas, especially near Amazyahu escarpment in the south. Rocksalt layers indicate deposition from more concentrated brine when the levels dropped to about -400 m m.s.l. Lower elevations could have been reached when the sea continued to shrink and when the runoff-to-evaporation ratio diminished, bringing the south basin to complete dessication. As neither the geochemical nature (ionic ratios) of the brines nor the physiography of the terminal water body has changed at least since Late Pleistocene or Lisan Lake time (Katz, Kolodny, and Nissenbaum, 1977), it is probable that through the past 60,000 years rocksalt was precipitated only when the water surface was at or below the critical level of -400 m m.s.l. Gamma-ray logs for some of the new coreholes provide more objective and precise depths of marl and rocksalt layers than do actual samples of sediments. Content of radiogenic minerals in the rocksalt is negligible compared with that in the marl; thus, these layers identify changing physical environments and climates as well as correlating stratigraphy. On gamma-ray logs the peaks or highest intensities of positive anomalies indicate that marl layers or wet climatic subphases and their thicknesses on the logs are proportional to their duration. Presence of negative anomalies or very low levels of gamma radiation show both the existence and thickness of rocksalt layers that denote dry climatic phases.

1998 ◽  
Vol 37 (6-7) ◽  
pp. 87-93 ◽  
Author(s):  
M. Kussmaul ◽  
A. Groengroeft ◽  
H. Koethe

In the year 1993 a confined and unused harbour basin was used to store 290,000 m3 of fine-grained dredged material from Hamburg harbour. About 70% of the deposit surface was water covered. The edge areas were above the water table and covered with reed. Emissions of dissolved compounds into the groundwater, as well as surface gas emissions were measured from 1994 to 1996. As indicators for water fluxes from the deposit we used NH4+ and HCO3− because of their high concentrations in mud porewater in comparison to groundwater. The average concentrations of NH4+ and HCO3− in the porewater increased during 2 years from 85 to 250 mg NH4+ 1−1 and from 2.0 to 3.1 g HCO3− 1−1, while the groundwater samples showed constant values of 8 mg NH4+ 1−1 and 0.7 g HCO3− 1−1. Furthermore, the average gas emissions over the water surface were 3.2 g CH4 m−2 d−1 and 0.8 g CO2 m−2 d−1. In contrast, no methane and 3.0 g CO2 m−2 d−1 were emitted from land areas. The results indicated, that there were no significant emissions of mud porewater compounds into the groundwater but high CH4-emissions over the water covered surface of the mud deposit.


1996 ◽  
Vol 57 (4-2) ◽  
pp. 493-500 ◽  
Author(s):  
Shin-ichi NAKANO ◽  
Yasushi SEIKE ◽  
Tatsuki SEKINO ◽  
Minoru OKUMURA ◽  
Keiichi KAWABATA ◽  
...  

2021 ◽  
Author(s):  
Ming Xie ◽  
Yunpeng Jia ◽  
Ying Li ◽  
Xiaohua Cai ◽  
Kai Cao

Abstract Laser-induced fluorescence (LIF) is an effective, all-weather oil spill identification method that has been widely applied for oil spill monitoring. However, the distinguishability on oil types is seldom considered while selecting excitation wavelength. This study is intended to find the optimal excitation wavelength for fine-grained classification of refined oil pollutants using LIF by comparing the distinguishability of fluorometric spectra under various excitation wavelengths on some typical types of refined-oil samples. The results show that the fluorometric spectra of oil samples significantly vary under different excitation wavelengths, and the four types of oil applied in this study are most likely to be distinguished under the excitation wavelengths of 395 nm and 420 nm. This study is expected to improve the ability of oil types identification using LIF method without increasing time or other cost, and also provides theoretical basis for the development of portable LIF devices for oil spill identification.


2001 ◽  
Vol 38 (11) ◽  
pp. 1601-1613 ◽  
Author(s):  
E A Christiansen ◽  
E Karl Sauer

The Saskatoon Low is a collapse structure that formed as a result of dissolution of salt from the Middle Devonian Prairie Evaporite Formation. In this study, the collapse has affected the Upper Cretaceous Lea Park, Judith River, and Bearpaw formations of the Montana Group; the Early and Middle Pleistocene Mennon, Dundurn, and Warman formations of the Sutherland Group; and the Late Pleistocene Floral, Battleford, and Haultain formations of the Saskatoon Group. Locally, the collapse is about 180 m, which is about equal to the thickness of the salt. The first phase of collapse took place after deposition of the Ardkenneth Member of the Bearpaw Formation and before glaciation or during a pre-Illinoian glaciation. The second phase of collapse occurred during the Battleford glaciation (Late Wisconsinan). Prior to deposition of the Battleford Formation, the Saskatoon Low was glacially eroded, removing the Sutherland Group and the Floral Formation. After the glacial erosion, up to 110 m of soft till of the Battleford Formation and up to 77 m of deltaic sand, silt, and clay of the Haultain Formation were deposited in the Saskatoon Low. Lastly, the South Saskatchewan River eroded up to about 40 m into the deltaic sediment and tills before up to about 15 m of Pike Lake Formation was deposited. The Haultain and Pike Lake formations are new stratigraphic units.


1933 ◽  
Vol 11 (1) ◽  
pp. 1-8
Author(s):  
S. Gladstone Solomon

In April, 1931, a collection of helminth parasites was received by the Imperial Bureau of Agricultural Parasitology from Mr. Bodkin, the Government Entomologist at Jerusalem. The specimens appear to have been collected by Native Meat Inspectors from slaughter houses, farms, etc., ranging through eleven different localities, from Hebron and Gaza, west of the Dead Sea, in the south; to Acre and Safad, north of the Sea of Galilee. The collection comprised 117 bottles of material, much of which had been rather poorly preserved. For such a large assortment of material the number of species is relatively small, as so many of the parasites were sent in duplicate. There does not appear to be any species new to science, and the following note is intended as a contribution to the zoögeography of a country whose parasitic fauna is somewhat inadequately known.


1988 ◽  
Vol 49 (3) ◽  
pp. 175-183 ◽  
Author(s):  
Masami NAKANISHI ◽  
Tetsuya NARITA ◽  
Norio SUZUKI ◽  
Osamu MITAMURA

Author(s):  
Chris Urwin ◽  
James W. Rhoads ◽  
Joshua A. Bell

The Papuan Gulf’s littoral coastline has been emerging and transforming since the late Pleistocene. Large river deltas such as the Fly, Kikori, and Purari transport sediments into the Coral Sea, and these are reworked by prevailing tides and seasonal currents to form a world of sand and swamps that Papuan Gulf peoples inhabit. This article reviews the archaeology of key sites in the region and identifies themes for future explorations of the region’s rich heritage. It explores how the region’s delta-dwelling societies occupied, modified, and made sense of their relatively fluid physical environments. Two aspects are explored in detail: (1) the potential to historicize the emergence of sago cultivation and its role in sustaining local settlements and long-distance trade; and (2) the contribution of nuanced spatial histories of migration and place-making to the region’s narrative.


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