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41.
The geochemistry of carbonate fault rocks has been examined in two areas of the Arava Fault segment, which forms the major branch of the Dead Sea Transform between the Dead Sea and the Gulf of Aquaba. The role of fluids in faulting deformation in the selected fault segment is remarkably different from observations at other major fault zones. Our data suggest reduced fluid rock interactions in both areas and limited fluid flow. The fault did not act as an important fluid conduit. There are no indications that hydrothermal reactions (cementation, dissolution) did change the strength and behavior of the fault zone, although the two areas show considerable differences with respect to fluid sources and fluid flow. In one area, the investigated calcite mineralization reveals an open fluid system with fluids originating from a variety of sources. Stable isotopes (13C, 18O), strontium isotopes, and trace elements indicate both infiltration of descending (meteoric and/or sea water) and ascending hydrothermal fluids. In the other area, all geochemical data indicate only local (small scale) fluid redistribution. These fluids were derived from the adjacent limestones under nearly closed-system conditions.  相似文献   
42.
Wetlands are a key archive for paleoclimatic and archeological work, particularly in arid regions, as they provide a focus for human occupation and preserve environmental information. The sedimentary record from 'Ayn Qasiyya, a spring site on the edge of the Azraq Qa, provides a well-dated sequence through the last glacial–interglacial transition (LGIT) allowing environmental changes in the present-day Jordanian desert to be investigated robustly through this time period for the first time. Results show that the wettest period at the site preceded the last glacial maximum, which itself was characterised by marsh formation and a significant Early Epipaleolithic occupation. A sedimentary hiatus between 16 and 10.5 ka suggests a period of drought in the region although seasonal rains and surface waters still allowed seasonal occupation of the Azraq region. Archeological evidence suggests that conditions had improved by the Late Epipaleolithic, about the time of the North Atlantic Younger Dryas. The changes between wet and dry conditions at the site show similarities to patterns in the eastern Mediterranean and in Arabia suggesting the Jordan interior was influenced by changes in both these regions through the LGIT climatic transition.  相似文献   
43.
Jordanian authorities have achieved a nearly one hundred percent connection rate to municipal water supply services in urban areas. Following this unusual achievement for a lower-income country, a private management contractor was introduced to the capital city Amman, along with a form of economic regulation. However, water rationing due to extreme water scarcity, amplified by high and irregular population growth, disproportionately affects the city’s low-income households. This paper investigates the status of water supply service and regulatory arrangements with respect to poor and vulnerable consumers who were targeted in a household survey in June/July 2005. It identifies specific regulatory challenges which were not within the remit of or addressed by the acting quasi-regulator and the water authorities. In its extremes of connection coverage, water scarcity and population, the management of water supply in Amman presages the pro-poor water service challenge of many, even lower income, economies irrespective of the extent to which they may achieve the access targets of the Millennium Development Goals.  相似文献   
44.
Carbon capture and sequestration (CCS) is one of the important options available for partially stemming greenhouse gas emissions from large point sources. The possibility of leaking from deep storage needs to be addressed. The Wadi Namaleh area in southern Jordan provides an interesting case study of how excess CO2 can be trapped in the form of carbonates in the near surface, even when the local geology is not obviously conducive for such a process.Carbonate veins are formed in surface alteration zones of rhyolite host rock in this arid region. The alteration zones are limited to areas where surface soil or colluvium are present. Oxygen, deuterium and carbon isotopes of the carbonates and near-surface ground water in the area suggest that the source of carbon is deep seated CO2, and that the carbonate precipitated in local meteoric water under ambient temperature conditions. Analysis of strontium in the carbonate, fresh rhyolite and altered host shows that the source for calcium is aeolian. Trace elements show that metal and REE mobility are constrained to the alteration zone.Thus, interaction of H2O, CO2 and atmospheric wet and dry deposition lead to the formation of the clayey (montmorillonite) alteration zone. This zone acts to trap seeping CO2 and water, and thus produces conditions of progressively more efficient trapping of carbon dioxide by means of a positive feedback mechanism. Replication of these conditions in other areas will minimize CO2 leakage from man-made CCS sites.  相似文献   
45.
The very low frequency-electromagnetic (VLF-EM) technique was used to delineate two sub-parallel lava tubes, faults and dikes in Umm El-Quttein area, NE Jordan. The investigation of the lava tubes was conducted through 22 VLF-EM profiles across lava strike; the length of profiles ranged from 700 to 1700 m. The lava tubes outcrop at two sites: Azzam cave and Al-Howa tunnel, characterized by slightly weathered basalt, columnar joints and fissure zones; qualitative interpretation of Fraser and Karous-Hjelt maps differentiate those zones as linear, elongated and circular anomalous zones. The 2-D tipper inversion of VLF-EM data and resistivity imaging had the potential to screen out three anomalous zones of likely resistivity contrast: the lava tube body with resistivity over 2500 Θ·m, the fractured zones with resistivity less than 500 Θ·m, and the host vesicular basalt with resistivity of 1500 Θ·m. The strike of lava tubes varied from SW to NE direction with depth less than 20 m and width from 10 to 30 m.  相似文献   
46.
Subsurface Upper Triassic sediments of northern Jordan represent part of a regressive evaporitic-clastic succession that marks the shrinkage phase of the Late Triassic basin in the northern parts of the Arabian Plate. Sabkhas developed along the basin margin, whereas, oolitic shoals formed on the deeper parts of the carbonate platform. The basin reached a drewdown stage in the Risha, Palmyra and parts of northern Iraq, where halite was precipitated. Local shales, marls and argillaceous limestones are the major source rocks. The total organic content values of the shales and carbonates range between 0.5–1.9%. The main reservoir rocks are the oolitic limestones with porosities of 8–20% and permeabilities that range between 0.01–80 md. Regional swells and troughs that were cut by normal and strike-slip faulting are the main structural styles in the area. Favourable conditions for hydrocarbon generation and accumulation may be found under the Hauran Basalts in NE Jordan.  相似文献   
47.
Since 1992 research on the Badia Programme, in north-east Jordan, has begun the process of identifying constraints on development and is suggesting where developmental potential still exists. Still, there are no proven development options to set alongside the traditional pastoralism. Perhaps in the future, service industries will provide the main additional employment opportunities, especially those serving the needs of international trade to and from Iraq and further east.  相似文献   
48.
The Dead Sea is the lowest spot on Earth. It is a closed saline lake located in the middle of the Jordan Rift Valley between Lake Tiberias and the Red Sea. Its major tributaries are the Jordan River itself and the Dead Sea side wadis. The Dead Sea has a unique ecosystem and its water has curative, industrial and recreational significance. The level of the Dead Sea has been continuously falling since the early 1930s at an average rate of 0·7 m per year. The water level, as of February 1998, is about 410·9 m below mean sea level. In this paper, a water balance model is developed for the Dead Sea by considering different hydrological components of this water balance, including precipitation, runoff, evaporation and groundwater flow. This model is calibrated based on historical levels of the Dead Sea. Different scenarios are investigated, including the proposed Dead Sea–Red Sea Canal. This project is supposed to halt the shrinking of the Dead Sea and restore it to pre‐1950 levels in the next century. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
49.
长江刀鲚营养成分分析与品质评价   总被引:1,自引:0,他引:1  
分析长江刀鲚肌肉的一般营养成分、水解氨基酸、游离氨基酸、脂肪酸组成及11种矿物质含量,并对其营养价值进行评价。结果显示:1)长江刀鲚肌肉的蛋白质、脂肪、水分、灰分含量(质量分数,下同)分别为16.97%、6.42%、73.64%、1.25%;2)肌肉水解氨基酸含量为13.73%,必需氨基酸组成基本符合WTO评分标准;3)在肌肉检出18种游离氨基酸中以活性氨基酸(γ-氨基丁酸)为主,占总量的63.50%,其中呈味氨基酸占蛋白氨基酸的35.20%,是长江刀鲚具有特殊鲜味的原因之一;4)共检出13种脂肪酸,包括5种饱和8种不饱和脂肪酸,其中不饱和脂肪酸含量高达67.16%,以油酸比例最高,为53.61%;5)微量元素组成比例与一般淡水鱼类不同,5种常量元素和6种微量元素中,锌铜比分别为19,锌铁比1.1。  相似文献   
50.
Summary. Combined analysis of P - and S -wave data from seismic refraction lines in Jordan has led to the derivation of a Poisson's ratio model for the crust. This model shows that the upper crust, including the sediments, has an average Poisson's ratio of around 0.25, except beneath NW Jordan where the sediments have a high ratio of around 0.32. However, the lower crust below about 20 km depth has high Poisson's ratios ranging from 0.29 to 0.32. These high Poisson's ratios may be interpreted mineralogically in terms of high feldspar and low quartz content in the rocks (e.g. gneiss, amphibolite) of the lower crust or fluid phases in the form of separated penny-shaped inclusions.  相似文献   
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