Environment lacustrine

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. 

Tetraterpenoids and polyterpenoids are minor components of higher plants and are generally overwhelmed by the input of those compounds from microbial biomass in marine and lacustrine environments or sedimentary rocks. The natural cyclic tetraterpenoids have a maximum of two alicyclic rings, and thus the saturated and aromatic derivatives are limited. The common parent skeltons are lycopane, carotane, l-(2 , 2 ,6 -trimethylcyclohexyl)-3,7,12,16,20,24-hexamethylpentacosane, and biphytane. ... 

Most of these clays were formed by the alteration of volcanic material and basic igneous rocks. A few analyses of gouge clay and hydrothermal alteration deposits are included. Volcanic-derived montmorillonites have been formed in marine and lacustrine environments and in a variety of weathering and terrestial environments. A... 

In contrast, a study of the Tertiary bentonite beds of Texas (Roberson,1964) revealed considerable variation in chemical composition. Although no chemical analyses were made, the ability of the various montmorillonites to contract to 10 A when treated with K indicates a wide variation in layer charge. These bentonites are believed to have altered in a lacustrine environment and some are believed to be detrital, possibly having been formed in soils. 

Geochemistry of Organic and Inorganic Sulfur in Ancient and Modern Lacustrine Environments... 

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. 

Controls on Sedimentary Sulfur Chemistry. The variability of sulfur geochemistry in lacustrine environments is due, in part, to the large concentration... 

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... 

TUTTLE ETAL. Geochemistry of Sulfur in Lacustrine Environments 145... 

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. 

Muller G., Irion G., and Fdrstner U. (1972) Formation and diagenesis of inorganic Ca-Mg carbonates in the lacustrine environment. iVaterwii. 59, 158-164. 

Figure 11 Long-chain alkylcyclopentanes are relatively abundant in the C40+ region of the chromatograms of most oils. Oils from marine (a), saline lacustrine (b), and freshwater lacustrine (c) environments can be differentiated on the basis of these alkylcyclopentane distributions. Marine oils have a distinct odd/even predominance pattern oils from saline lacustrine environments demonstrate a high even/odd predominance pattern, and freshwater lacustrine oils are characterized by a low even/odd to no clear predominance pattern.

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. 

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