Yoram Eckstein

Measurement and interpretation of terrestrial heat flow in Israel

Abstract Sixty-eight new determinations of terrestrial heat flow in Israel have a range of 0.17-11.07 μcal/cm 2 s. The average value of deep conductive heat flow in the undisturbed complex of the Arabo-Nubian Massif is 0·94 μcal/cm 2 s; it is least affected by circulation of groundwater. This value is only slightly higher than the heat flow of 0·88 μcal/cm 2 s in the Levantine Basin of the Mediterranean Sea. Several values that exceed 2·0 μcal/cm 2 s are due either to (probable) deep hydrothermal activity or to small domal structures of the basement. Within the sedimentary sequence which blankets the crystalline massif, terrestrial heat flow is often redistributed by circulating groundwater. Recharge regions, particularly Judean-Samarian Galilee, where cool meteoric waters percolate into the subsurface have anomalously low heat flow, ranging from 0·17 to about 1·0 μcal/cm 2 s. Part of the original deep thermal flux in those regions is intercepted at moderate depths by the recharge flow, and is carried into deeper aquifers of the Foothills, Coastal Plain, or the Jordan-Dead Sea Rift. Movement of groundwater occurs mainly along faults. Deep faults associated with the Jordan-Dead Sea Rift system act as conduits for hot waters ascending from deep confined aquifers. The most tangible surface expression of the convective hydrothermal system are the numerous warm to hot springs, emerging along the margins of the Rift. However, the waters emerging on the surface as the warm and hot springs are a minor fraction of the convective system. Most of the ascending thermal waters are absorbed by shallow aquifers with lower hydraulic potential. Such regions are characterized by anomalously high heat flow; several values exceed 2 and one value is 11 μcal/cm 2 s.

Review of Heat Flow Data from the Eastern Mediterranean Region

Heat flow data from the eastern Mediterranean region indicates an extensive area of low heat flow, spreading over the whole basin of the Mediterranean east of Crete (Levantine Sea), Cyprus, and northern Egypt. The average of the marine heat flow measurements in the Levantine Sea is 25.7 ± 8.4 mW/m2, and the heat flow on Cyprus is 28.0 ±8.0 mW/m2. The estimated values of heat flow in northern Egypt range from 38.3 ± 7.0 to 49.9 ±9.3 mW/m2, apparently with no consistent trend. To the east, on the coast of Israel, the heat flow values increase, ranging from 36.6 ± 22.4 to 56.7 ± 14.2 mW/m2 along a SSE trend. The trend apparently correlates with an increase in crustal thickness, which is about 23 km at the north-west base of the Nile-Delta-cone, and close to 40 km beneath Israel.

Finite-element simulation of low-temperature, heat-pump-coupled, aquifer thermal energy storage☆

Abstract A two-dimensional, Galerkin finite-element, transport model was applied to a feasibility study of low temperature, heat pump coupled, aquifer thermal energy storage in a confined sandstone aquifer in northeastern Ohio. Simulations were run to determine the relative sensitivity of the model to transient versus steady-state radial flow, grid size, time-step lengths, and injection temperatures. In order to determine the effects of uncertainties in the values of aquifer and aquitard parameters, energy recovery factors and recovery temperatures were calculated for worst-case, best-case, and best-estimate simulations. Aquifer and aquitard parameters were either measured directly or were estimated based on previous hydrogeologic investigations. All simulations were performed assuming a 150 d injection phase with a pumping rate of 15 m 3 h −1 , a 35 d storage phase, and a 150 d production phase, also with a pumping rate of 15 m 3 h −1 . The worst-case simulation for an injection temperature of 23.9°C produced an energy recovery factor of 0.43 and a final production temperature of 14.6°C. The best-case simulation resulted in an energy recovery factor of 0.69 and a final production temperature of 16.2°C. The best-estimate simulation predicted an energy recovery factor of 0.50 and a final production temperature of 15.0°C. Both the energy recovery factor and the recovery temperature were most affected by the uncertainty in the storage formation longitudinal dispersivity. Using the best-estimate parameter values, an injection temperature of 18.0°C resulted in a final production temperature of 13.2°C and an energy recovery factor of 0.50. The best-estimate parameter values used with an injection temperature of 27.0°C yielded a final production temperature of 15.9°C and an energy recovery factor of 0.50.

Groundwater Resources and International Law in the Middle East Peace Process

Abstract Next to issues of land, water resources are the major bone of contention in the peace negotiations between Israel and the Palestinian Arabs. The objective of negotiations is de facto setting the clock back to the eve of the Israel War of Independence, when the Jews accepted the 1947 UN resolution of partition, while the Arabs rejected it. The Arabs now accept the principle of territorial partition, but at the same time, they demand re-apportioning of resources, mainly of water. The Palestinians contend that the facts created on the ground unilaterally by Israel during the last 50 years, namely the agricultural development and the high water consumption by the Israeli urban sector, leave them without resources necessary for their development as a modern society. Per capita annual renewable freshwater resources in the region is among the lowest in the world. Approximately 600 million m3, or about one-third of the regional fresh groundwater consumption, is annually abstracted from aquifer systems recharged at the uplands of the Upper Cretaceous partly karstified carbonate formations of Judea and Samaria, terrenes often referred to as the West Bank. Israel and the Israeli agricultural settlements established within Judea and Samaria use 495 million m3/year (or 82.5 percent) of the abstracted water, leaving to the Palestinians the remaining 105 million m3/year. Thus, while the recharge zone to the Judean and Samarian aquifer systems are within the territories with an overwhelmingly Palestinian majority, most of the discharge occurs through water wells within the Israeli administration. The situation is reversed in the Gaza Strip, where Israel allows underflow of only 7 million m3/year of groundwater across the border, a less than 10 percent contribution to the nearly 80 million m3/year overdrawn water budget of the area. The issue of water is complicated by glaringly wide disparity in per capita water consumption between the two nations. While lines on the ground may separate two nations with conflicting territorial ambitions, apportioning of groundwater between Israel and the future Palestinian State proves to be one of the most intractable issues in the Middle East Peace Process. Moreover, neither international nor domestic law provides an adequate answer to questions of ownership or rights.

A Computer Program for a Trilinear Diagram Plot and Analysis of Water Mixing Systemsa

The Piper (1953) trilinear diagram has been widely used to graphically represent the dissolved constituents of natural waters and to test for apparent mixtures of waters from different sources. Because of the time required to plot points and calculate the proportional values of mixing, this treatment of data was often quite tedious, particularly in studies involving large numbers of chemical analyses. The PIPER program was written in BASIC to be run on a Hewlett-Packard desktop computer with an X-Y plotter. Data input is in ppm units. The program plots points in all three fields of the trilinear diagram, draws at each point within the central diamond field a circle with a radius correspondent to the concentrations expressed in meq/1, checks for points that fall on a straight line (or within a predetermined tolerance of a straight line) representing postulated mixtures with two end members, and/or within a triangle representing mixtures of three end members. Finally, the program does a numerical analysis of the mixing ratios of the constituents for postulated mixing systems according to the methodology as presented by Piper (1953).

Correlation between the silica concentration and the orifice temperature in the warm springs along the jordan-dead sea rift valley

Abstract Analysis of twenty-one thermal springs emerging along the Jordan-Dead Sea Rift Valley in Israel indicates a very good correlation between the concentration of dissolved silica and the temperature of the spring orifice. Dissolution of quartz was identified as the apparent source of the silica in the water. Application of the silica geothermometer for mixed systems suggests that the springs in the Tiberias Lake Basin are supplied with hot water from deep reservoir (or reservoirs) at a temperature of 115°C (239°F). The same temperature was postulated earlier by the application of the Na-K-Ca hydro-geothermometer to a group of thermal springs in the same basin. The temperature of the reservoir supplying hot brines to the springs emerging along the western shore of the Dead Sea is estimated at 90°C (194°F).

Evaluation of soil water residence time in a monolith lysimeter from the application of queueing disciplines to water budget data (Demonstration — II)☆

Abstract Soil water residence time in a monolith lysimeter at the North Appalachian Experimental Watershed was estimated by applying queueing disciplines to the lysimeter water budget data. The lysimeter contains an undisturbed soil block measuring approximately 6 ft wide, 14 ft long and 8 ft deep, and a permanent grass cover is maintained on the soil. The lysimeter water budget data used consist of monthly totals of precipitation, evapotranspiration, runoff and percolation for the period of January, 1947–December, 1985. The three following queueing discipline models were applied to the water budget data: (a) all of the water in the lysimeter follows first-in-first-out (FIFO) queueing discipline; (b) all of the water in the lysimeter follows last-in-first-out (LIFO) queueing discipline; (c) discharge by evapotranspiration follows LIFO queueing discipline and discharge by percolation follows FIFO queueing discipline. The FIFO model generated minimum residence times of three months and maximum residence times of eleven months with approximately half the assigned values being six months or less. The LIFO model generated minimum residence times of less than one month and a maximum of 140 months. More than half of the values were less than one month. The combined LIFO-FIFO model generated minimum residence time of less than one month and a maximum residence time of 63 months with half of the values being less than six months. The FIFO model tended to assign the higher residence time values to water that entered the lysimeter in the summer months, while the LIFO and LIFO-FIFO models tended to assign the high residence time values to water that entered the soil in the winter months.

Principles of evaluation of soil water residence time using queueing disciplines with water budget data (Theoretical background—I)☆

Abstract Soil water residence time is an important aspect of soil hydrology. It is an important factor affecting the chemical composition of water in the soil. Water that makes up recharge and discharge to and from a hydrologic reservoir can be considered to consist of individual increments of water called fluid elements. Queueing disciplines can be used to describe the order in which the fluid elements move through the reservoir. Possible queueing disciplines that can be related to soil water movement are last-in-first-out (LIFO), first-in-first-out (FIFO), and a combination of LIFO and FIFO. When water budget records are available, the queueing disciplines can be used as models to allow the calculation of residence time estimates. Computer algorithms have been written for the purpose of making estimates of soil water residence times in a weighable monolith lysimeter.

Using inverse modeling and hierarchical cluster analysis for hydrochemical characterization of springs and Talkhab River in Tang-Bijar oilfield, Iran

Hierarchical cluster analysis (HCA) and inverse modeling (PH REdox EQuilibrium (in C language) (PHREEQC)) were simultaneously useful approaches in interpreting surface water hydrochemistry within Talkhab River in the Tang-Bijar oilfield, Iran, where large uncertainties exist in the understanding of the water quality system. Q-mode HCA applied to the data revealed three major surface water associations distinguished on the basis of the major causes of variation in the hydrochemistry. The three water groups were classified as upstream waters (group 1: Ca–SO4), intermediate waters (group 2: Ca–SO4–Cl), and downstream waters (group 3: Na–Cl). Geochemical reaction models were constructed using PHREEQC to establish the reactions associated with the different mineral phases through inverse modeling. The hydrochemical compositions of the water groups and the mass balance calculations indicate that the dominant processes and reactions responsible for the hydrochemical evolution in the system are (1) dissolution of evaporites, (2) precipitation of carbonate minerals, (3) silicate weathering reactions, (4) limited mixing with saline water, and (5) ion exchange.

Modeling the neutralizing processes of acid precipitation in soils and glacial sediments of northern Ohio

Abstract Most studies of the acidic deposition phenomena have been focused on processes occurring in the northeastern USA and Scandinavia. In these regions the soil cover is thin, the bedrock is acidic, and the terrain has very poor acid buffering capacity. Most of the US Midwest, including northern Ohio, has been ignored because the terrain is covered by glacial sediments with an abundance of carbonate minerals. Yet, for the last three decades the area has been experiencing acidic precipitation with a pH range of 3.5–4.5. the lowest in the USA. Samples of precipitation, soil water, and shallow ground water from Leroy Township in Lake County, Ohio, and from Wooster Township in Wayne County, Ohio, were analyzed and processed using WATEQ3 and PHREEQE computer models to quantify the effects of the acidic deposition. The two regions are characterized by very similar topographic, geological and hydrogeological conditions. Although the cation content of the precipitation in both regions is similar, the anion concentrations are much higher (sulfate by 70%, nitrate by 14% and chloride by 167%) in Leroy, located 50 km east-northeast and downwind of the Cleveland-Akron industrial complex, than in Wooster, located 80 km south-southwest and off-wind from the industrial complex. Computer modeling results indicate that buffering of acidic deposition in the surficial sediments and glacial tills of the two regions is dominated apparently by calcite dissolution, and dissolution and exchange of hydrogen for magnesium ions are the dominant neutralizing processes. However, reaction simulations also suggest that the buffering capacity of the Leroy soils and tills has been depleted to a much greater degree than in Wooster Township. In Leroy more acidic input is reacting with less buffering material to produce lower soil and groundwater pH. The depletion of carbonate and alumino-silicate minerals in the soils of Leroy Township is occurring at a rate that is 3–5 times faster than in the same type of soils in Wooster Township.