Deep basins

Petroleum reservoirs, however, occur in a gray facies of the Lyons found in the deep basin (Levandowski et al., 1973). This facies contains no ferric oxides... 

Flow in the Pennsylvanian Fountain formation, a sandstone aquifer that underlies the Lyons and is separated from it by an aquitard complex, was more restricted because the formation grades into less permeable dolomites and evaporites in the deep basin. Groundwater in the Fountain recharged along the Front Range and... 

Leach, D. L., G. S. Plumlee, A. H. Hofstra, G. P. Landis, E. L. Rowan and J. G. Viets, 1991, Origin of late dolomite cement by C02-saturated deep basin brines evidence from the Ozark region, central United States. Geology 19, 348-351. 

Basinal settings (a) shallow-water, deep basin (b) deep-water, deep basin (c) shallow-water, shallow basin (epicontinental or epeiric sea). Source. From Kendall, A. C. (1984). Facies Models 2nd ed.. Geoscience Canada Reprint Series, Walker, R. G., ed. pp. 259-296. 

These include (1) tight sandstones, (2) Devonian shales. (3t geopiessured zones, (4) deep basins, (5) gas associated with coal seams, and (6) gas in the form of methane hydrates. 

Deep Basins. These are found at depths between 15,000 and 30,000 feel (4572 -9144 meters) and arc estimated to contain significant quantities of gas, but generally await the development of advanced production technology and economic incentive. 

Figure 4 illustrates the results of this type of analysis for a deep-basin solar still in the San Diego area. Thermal radiation from basin to cover is the largest loss, followed by reflection of solar radiation from the cover and air convection inside the still. Solar utilization efficiency is the height of the lowest curve as a fraction of the height of the top curve, ranging from about 30% in January to 50% through the summer months. 

Figure 4. Predicted average performance of deep-basin solar distiller in San Diego area...

Lof, G. 0. G., Design and Evaluation of Deep-Basin, Direct Solar Heated Distiller for... 

Construction methods and performance data are presented on solar sea water stills under evaluation at the Florida Solar Distillation Research Station. Three stills representing two basic designs have been constructed and operated there a 2500-sq.-foot glass-covered deep-basin still and 2300- and 500-sq.-foot air-supported plastic stills. Other types of stills are being developed for future construction and field evaluation. 

Figure I. Solar still evaluation area as viewed from lighthouse Deep-Basin Still...

Construction. The deep-basin still was conceived and designed initially by George 0. G. Lof, Engineering Consultant, Denver, Colo., a consultant to the Office of Saline Water. As built at the Florida station, the still has served mainly as a research tool rather than as a demonstration of the lowest possible cost of construction. Construction was started in the summer of 1958 and completed in January 1959. The unit has been in operation about 7 months, operation having been suspended several times so that various improvements could be made. 

Figure 2 is a photograph of the deep-basin still. The concrete curbing shown along the near edge of the still is part of a heat-exchanger flume in which feed water can be preheated. 

Figure 2. Glass-covered deep-basin still...

Performance. So far, the deep-basin still has been operated only under batch-type control—that is, without continuous blowdown or heat exchange to the incoming sea water. In determining the performance of the still, incident solar radiation and distillate production are measured daily. From this information, the specific production in gallons per square foot per day and the thermal efficiency can be determined. In addition to the daily collection of performance data, hourly collections are made during periodic energy- and mass-balance runs. 

Figures 4 and 5 show the daily and the average monthly productivity of the deep-basin still at various solar-radiation intensities. The scatter of data points for the daily...

Figure 4. Variation with solar radiation of average daily distillate production of deep-basin still...

Distribution of Energy. During a 3-day period, October 7 to 9,1959, a continuous performance run was made on the deep-basin still for the purpose of computing an energy balance. Each item pertinent to the energy balance was measured, except convection loss to the atmosphere, which was obtained by calculations. The experimentally determined losses were then compared with the corresponding calculated losses. These showed remarkably close agreement. 

Table I gives the distribution of the energy input to the deep-basin still as determined from the results of the 3-day energy balance. As shown, 32% of the available energy was utilized for useful output of the still. The largest single loss, 25%, was heat radiation from the basin water. The remainder of the heat losses, taken separately, are relatively moderate collectively, however, they account for about 43% of the incoming solar energy.

Methods of Improving Deep-Basin Still. As shown in Table I, the sum of the ground and edge losses from the deep-basin still was only 2%. This is especially noteworthy in view of the fact that the bottom of the basin is not insulated, and suggests that insulation of the basin of a large still probably could not be justified economically. 

Figure 7 is a photograph of the 2300-sq.-foot air-supported plastic still. This still consists of rows of separate channels, each provided with a waterproof plastic basin and an air-supported transparent plastic cover. The design incorporates a relatively shallow basin, containing only a few inches of water, so that there is much less thermal inertia than in the deep-basin still. 

Algae growth did not occur in the stills when sea water feed was used, but developed on several occasions when brackish well water was supplied to the deep-basin still. 

About 8 million km3 or 30.8% are under ground in the form of ground water (in shallow and deep basins at depths of 2,000 m), soil moisture, marsh water, and permafrost. 

Land (1987) has reviewed and discussed theories for the formation of saline brines in sedimentary basins. We will summarize his major relevant conclusions here. He points out that theories for deriving most brines from connate seawater, by processes such as shale membrane filtration, or connate evaporitic brines are usually inadequate to explain their composition, volume and distribution, and that most brines must be related, at least in part, to the interaction of subsurface waters with evaporite beds (primarily halite). The commonly observed increase in dissolved solids with depth is probably largely the result of simple "thermo-haline" circulation and density stratification. Also many basins have basal sequences of evaporites in them. Cation concentrations are largely controlled by mineral solubilities, with carbonate and feldspar minerals dominating so that Ca2+ must exceed Mg2+, and Na+ must exceed K+ (Figures 8.8 and 8.9). Land (1987) hypothesizes that in deep basins devolatilization reactions associated with basement metamorphism may also provide an important source of dissolved components. 

A comparative analysis of the hydrodynamical situations that occurred in different years has made it evident that anticydonic eddies may represent a typical element of the circulation in the eastern deep basin at least during the warm season (April-December). This fact contradicts the traditionally accepted concept (see [1-3]). The appearance and existence of these kinds of anticydonic eddies in the deep basin is related to the separation of coastal anticyclones from the coast. Some events of this kind together with the subsequent movement of the deep-sea anticyclones were registered with the use of satellite information of high spatio-temporal resolution and derived from the hydrographic surveys of different years. 

Ginzburg AI, Kostianoy AG, Soloviev DM, Stanichny SV (2000) Remotely sensed coastal/deep-basin water exchange processes in the Black Sea surface layer. In Halpern D (ed) Satellites, oceanography and society. Elsevier, Amsterdam, p 273... 

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