Lakes environments, lacustrine

A) Classification of lacustrine sedimentation in Jura Mountains lakes. (B) Aerial and (C) field view from the palustrine (marsh) zone towards the deep lake (Lake Neuchatel, Switzerland) in a hard-water lake environment. 

Morgan, J. J. and Stone, A. T. (1985). Kinetics of chemical processes of importance in lacustrine environments. In Chemical Processes in Lakes" (W. Stumm, ed.). Wiley, New York. 

Aggett, J. and G.A. O Brien. 1985. Detailed model for the mobility of arsenic in lacustrine sediments based on measurements in Lake Ohakuri. Environ. Sci. Technol. 19 231-238. 

First we review controls on the amount and isotopic composition of various forms of sulfur in lacustrine environments. Next, we summarize the diverse behavior of sulfur in sediment from two freshwater environments in sediment from three modern, productive, saline lakes and in oil shales deposited in freshwater and saline lacustrine environments. Lastly, our results are integrated in order to produce models that 1) predict the extent of formation and isotopic composition of sulfide minerals in response to major controls on sulfur geochemisty and 2) show the formational pathway of organosulfur in lacustrine oil shale and its derivative oil. 

Depositional and Diagenetic Behavior of Sulfur. The key controls on sulfur behavior in freshwater-lake, saline-lake, and marine sediments include the concentration of reactants for bacteriogenic H2S formation and sulfide-mineral formation. Table IV illustrates the relative importance of the independent reactants (organic matter, dissolved sulfate, and iron) in each of the lacustrine environments studied. We have shown that in saline... 

Alkali (monovalent) carbonate minerals also can occur in sediments. These phases have been studied in association with lake sediments. Their formation in these lacustrine environments has been used to deduce the conditions under which they formed based on their phase relations (see Figure 2.5). These phases usually precipitate during the late stages of evaporation of saline waters. 

Valero-Garces B. L., Arenas C., and Delgado-Huertas A. (2(X)1) Depositional environments of quaternary lacustrine travertines and stromatohtes from higji-altitude Andean lakes, nOTth-westem Argentina. Can. J. Earth Sci. 38, 1263—1283. 

Tuttle M. L., Rice C. A., and Goldhaber M. B. (1990) Geochemistry of organic and inorganic sulfur in ancient and modern lacustrine environments case studies of freshwater and saline lakes. In Geochemistry of Sulfur in Fossil Fuels (eds. W. L. Orr and C. M. White). American Chemical Society, Washington, DC, pp. 114-148. 

In these examples as well as for most aquatic sediments, the principal diagenetic reactions that occur in these sediments are aerobic respiration and the reduction of Mn and Fe oxides. Under the slower sedimentation conditions in natural lakes and estuaries, there is sufficient time (years) for particulate organic matter to decompose and create a diagenetic environment where metal oxides may not be stable. When faster sedimentation prevails, such as in reservoirs, there is less time (months) for bacteria to perform their metabohc functions due to the fact that the organisms do not occupy a sediment layer for any length of time before a new sediment is added (Callender, 2000). Also, sedimentary organic matter in reservoir sediments is considerably more recalcitrant than that in natural lacustrine and estuarine sediments as reservoirs receive more terrestrial organic matter (Callender, 2000). 

McKenzie, J. A. (1985) Carbon Isotopes and Productivity in the Lacustrine and Marine Environment. In Chemical Processes in Lakes, W. Stumm, Ed., Wiley-Interscience, New York. 

Pan/lacustrine silcretes (Figure 4.5B, C) most commonly develop within, or adjacent to, ephemeral lakes, pans or playas within endoreic basins (Goudie, 1973 Summerfield, 1982 Figure 4.10C). In the majority of modern evaporitic lacustrine environments, silica precipitation is driven by changes in pH and salt concentration (Thiry, 1999), both of which can... 

Lakes can be described as any natural terrestrial depression filled up with free and quiet water without a connection to the ocean. The surface of lakes varies from several tens of thousands of kilometres2 to a minimum of 10,000 m2 (or 10,000 m3). When the water body has a mean depth of [Pg.298]

Figure 9.8 (A) Clayey and calcareous diatomite from northern Lake Chad. Various sedimentary layers can be seen they correspond to transition from a lacustrine environment (bottom) to a palustrine environment (top), from sub-arid to arid conditions. (Photograph courtesy of Professor A. Durand.) (B) Spherule-like crystals of kenyaite (hydrous sodium silicate) precipitated in apolyhaline interdunal ponds, Lake Chad.

Evaporite precipitation spans a large variety of lacustrine environments, from permanent saline lakes to commonly dry flat basins, the latter the... 

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