Biostratigraphy and paleogeography of the southeast desert phosphorites of Jordan

Three sections from the Al-Hisa Phosphorite Formation (AHP) were measured in the southeastern desert of Jordan: Batn El-Ghoul, Nagb Etayyeg, and Zgaimat Al-Hasah. A fourth section, Wadi Arfa, is added from a previous work. The three sections differ from the typical AHP Formation in central Jordan by having highly reduced thicknesses, omission/non-deposition of the underlying formations, rarity of fossils, abundant sand, and their stratigraphic ages. A Paleocene-Early Eocene age, based on calcareous nannofossils, has been assigned to the AHP Formation of the sections studied in the southeast desert. This Paleocene-Early Eocene age is younger than the Early Maastrichtian age of the AHP deposits in central Jordan. The published ages of the phosphorite deposits in the eastern Mediterranean countries suggest a younging to the east due to an interplay between paleodepositional environments and plate tectonics (paleohigh formation). The minor phosphorite deposits of Turkey and Iran are not involved in the discussion because they were not part of the Afro-Arabian Plate or the later Arabian Plate. The abovementioned differences between the southeastern desert phosphorites and the central Jordan deposits are here explained by the formation of paleohighs on the Neo-Tethys seafloor during the Late Cretaceous-Eocene. These include the Sirhan Paleohigh where the southeast desert phosphorites were deposited. The formation of the highs was due to the compression associated first, with the subduction of the Afro-Arabian Plate, below the Eurasian Plate and later with their collision.     

Oil in parallax: Scarcity, markets, and the financialization of accumulation

Relations between oil scarcity, production, investment, and price have become increasingly mediated and shaped by financial markets. Yet, the mediation of finance is absent in peak oil narratives, which posit a direct relation between the availability of oil in the ground and its price on the market. The orthodox critique of peak oil deconstructs its basis in geological limits only to reproduce the argument from scarcity and reverse the relationship between the price of oil and its availability on the market. Both narratives are formulated in physical space and do not account for the degree to which the oil market has become infused by the logic of finance. Critical political economy, on the other hand, demonstrates the extent to which finance has transformed capital accumulation, only to render material production somewhat irrelevant to the accumulation of capital. This is equally problematic, given oil companies’ continuing investment in production and reserve expansion. The relation between accumulation, investment, and production under finance needs to be examined rather than discarded. I argue that finance has emancipated the circulation of oil in the world market from its circulation in physical space, fragmenting the oil market into a physical and a financial component, but reintegrating both under the dominance of financial logic without transcending their duality and their differences. I explicate this relation by examining the circulation of oil in trade and investment under the dictates of finance to open questions on current theorizations of oil scarcity in relation to prices, markets, and investment.     

Porothermoelastic analyses of anisotropic hollow cylinders with applications

It has been known that material anisotropy and thermal stresses affect borehole stability significantly. Aiming at the experimental studies associated with borehole stability in anisotropic (transversely isotropic) poroelastic materials subject to non‐isothermal conditions, this paper details and applies an anisotropic porothermoelastic solution to an unjacketed hollow cylinder in a triaxial set‐up. Numerical analyses are presented to demonstrate thermal and material anisotropy effects on the pore pressure and the stress concentrations in and around the geometry of a hollow cylinder subjected to thermal and stress perturbations. Copyright © 2004 John Wiley & Sons, Ltd.     

Evaluation of the effect of water management interventions on water level of Gaza coastal aquifer

Gaza coastal aquifer (GCA) is the most precious natural source where it is the only source of water for different uses. Groundwater crisis in Gaza includes two major folds: shortage of water supply and contamination. The extraction of groundwater currently exceeds the aquifer recharge rate. As a result, the groundwater level is falling continuously leading severely deterioration of GCA. The main objective of this study is to analyze and evaluate the current and proposed water resources management plans and their effect on the water level of GCA. In this respect, the available quantities of rainfall that could be harvested and infiltrated from different types of land-use based on existing and planned situations are studied using GIS tool and numerical models for GCA using V-MODFLOW environment for simulating four scenarios: (i) existing management practice (no action scenario), (ii) proposed Palestinian Water Authority (PWA) stormwater infiltration plan, (iii) proposed Gaza Emergency Technical Assistance Program (GETAP) interventions, and (iv) combination between second and third scenarios. The management scenarios were tested with the calibrated flow model for the target period between 2016 and 2040. The simulation results of existing management practice scenario show that there are several depression zones in Gaza Strip; in southern part from ??18 to ??24 m MSL in 2020 and 2040, in the northern part from ??7 to ??12 m MSL in 2020 and 2040, and in the middle regions experienced a small decline in groundwater level. The simulation results of proposed PWA scenario indicate similar depression zones as per first scenario but with good enhancement of water level, ??17 to ??18 m MSL in the southern part and ??3 to ??6 m MSL in the northern part in 2020 and 2040, respectively. The simulation results of GETAP intervention scenario show a positive impact on groundwater level. The results of fourth scenario show good enhancement of water level, in which the water level in the northern part ranges from +?3 to +?6 m MSL in 2020 and 2040, while in the south part ranges from ??15 to +?4 MSL in 2020 and 2040.     

Tectono sedimentary evolution of the Umm Ghaddah Formation (late Ediacaran-early Cambrian) in Jordan

The terrestrial Umm Ghaddah Formation of late Ediacaran-early Cambrian age was deposited in NE–SW elongated intracontinental rift system basins and sub-basins bounded by active listric half-graben faults. Basin fill consists of conglomerate facies association A, deposited in a fault-controlled transverse alluvial fan system that drained northwestward and graded laterally into sandstone facies association B, deposited by a braided river system flowing northeastward axial to the rift basin. The alluvial fan facies association was deposited by rock falls and non-cohesive debris flows of sediment gravity flow origin, and by sheetflood processes.The Umm Ghaddah Formation is dominated by a large-scale fining upward succession interpreted to reflect a gradual cessation of the Pan African Orogeny. Within this large-scale trend there are also minor fining and coarsening upward cycles that are attributed to repeated minor tectonic pulses and autocyclic shifting of the system.The distribution pattern of the Umm Ghaddah Formation and the underlying Ediacaran Sarmuj Conglomerates, Hiyala Volcaniclastics and Aheimir Volcanics in Jordan and adjacent countries in isolated extensional half-grabens and grabens formed during the extensional collapse phase of Arabia associated with the Najd Fault System seems to be unrelated to the present day Wadi Araba-Dead Sea transform fault system.     

Numerical modeling of brine disposal from Gaza central seawater desalination plant

Gaza central seawater desalination plant is a promising solution to alleviate the problem of water crisis in the Gaza Strip. The plant in the short term, phase (I), will desalinate seawater for potable uses with a capacity of 55 million cubic meters per year, while in the long term, phase (II), the plant capacity will be doubled to 110 million cubic meters per year of freshwater. As a product from the reverse osmosis process, a huge amount of brine with salinity reaches to 75,000 mg/L will be redirected to seawater; nearly 12,200 m³/h of brine will be rejected from phase (I) while in the long term, a brine flow rate of 24,400 m³/h will be disposed from phase (II). In order to minimize the negative impacts of the rejected brine on the marine environment, it is urgent to modeling numerically the impact of the discharged brine through various disposal systems to define the most environmental system. Various scenarios were defined and simulated using CORMIX model to study the efficiencies of onshore surface open channel, offshore submerged single port as well as offshore submerged multiport outfalls taking salinity variations as an indicator. Sensitivity analysis was conducted to identify the most influencing input parameters on the simulation results as well as to evaluate the optimal environmental disposal system which can mitigate the adverse impacts of brine on the marine ecosystem as much as possible in the worst seawater conditions. The simulation results showed that the discharge via surface open channel is not environmentally feasible where the seawater salinity rose by more than 2000 mg/L at RMZ. The single-port scenario can meet the regulations at RMZ but the standard at GMZ was not met, where the rejected brine from phase (I) through single port at 1500 m offshore raises the seawater salinity at GMZ by more than 600  mg/L. The staged multiport outfall, capped by 24 ports, achieves acceptable brine dilution at seawater depth of about 7.5  m, and in the worst ambient conditions in the case of phase (II) in operation, the brine’s excess salinity was 536, 497, and 379 mg/L above the salinity of seawater at RMZ, GMZ, and ROI, respectively.     

Rocking,wobbling and overturning of the multidrum columns of Baalbek under periodic pulses

Journal of Seismology - A three dimensional distinct element model was developed for the multiblock Baalbek columns to investigate the response of the existing columns as well as 0.5m and 1m scaled...     

An improvement in mass flux convective parameterizations and its impact on seasonal simulations using a coupled model

A new closure and a modified detrainment for the simplified Arakawa–Schubert (SAS) cumulus parameterization scheme are proposed. In the modified convective scheme which is named as King Abdulaziz University (KAU) scheme, the closure depends on both the buoyancy force and the environment mean relative humidity. A lateral entrainment rate varying with environment relative humidity is proposed and tends to suppress convection in a dry atmosphere. The detrainment rate also varies with environment relative humidity. The KAU scheme has been tested in a single column model (SCM) and implemented in a coupled global climate model (CGCM). Increased coupling between environment and clouds in the KAU scheme results in improved sensitivity of the depth and strength of convection to environmental humidity compared to the original SAS scheme. The new scheme improves precipitation simulation with better representations of moisture and temperature especially during suppressed convection periods. The KAU scheme implemented in the Seoul National University (SNU) CGCM shows improved precipitation over the tropics. The simulated precipitation pattern over the Arabian Peninsula and Northeast African region is also improved.

     

Stability of Solution Cavities in Urban Developments: A Case Study Towards Enhancing Geohazard Risk Assessment

Karst cavities in fissured soluble rock represent serious geotechnical hazard for civil construction and urban development. The process of cavity formation, expansion, and propagation is difficult to predict because it is driven by a combination of diverse causes, such as the dissolution rate of rock; flow of groundwater; amount of fine material within rock layers; presence of loose, uncontrolled fill over the rock; and the leakage of underground utilities. Several factors can affect cavity stability, including cavity geometry and dimensions, cavity depth, overburden surface-layer lithology, and surface-loading conditions. This paper presents a case study for karst cavities stability in the Abu Dhabi Municipality (ADM) of the United Arab Emirates as part of a comprehensive study initiated by the ADM to address the geotechnical, geologic, and hydrogeological hazards encountered in the municipality. The purpose of this study is to develop a methodology for assessing karst cavities stability in the ADM, and thereby, quantify their potential hazard for civil construction and urban development in the municipality. A numerical study is performed, using a finite difference model that is based on site-specific ground conditions encountered in a localized area. Results from this numerical investigation are presented in the form of stability charts for different lithologic and surface-loading conditions. These charts are used to develop a set of geographic information system cavity-collapse geohazard maps for the study area to factor solution cavity-collapse risk into an integrated geohazard map for the ADM. Based on available information and the case study presented herein, it is concluded that the collapse of solution cavities do not significantly contribute to the geotechnical hazard observed in the ADM.