Lacustrine Clay Sedimentation

Abstract

Like desert, glacier and river deposits, lake sediments may include most of the minerals issued from igneous, metamorphic and sedimentary rocks. This is especially the case of freshwater sediments, that commonly include numerous nonclay and clay silicates, various carbonates, Fe-Mn oxides, phosphates, sulfides, and fluorides (see Jones and Bowser’s review, 1978). Mite and smectite constitute the dominant species, and are as frequently encountered as quartz. Chlorite, kaolinite, mixed-layers and palygorskite are variously present, depending on the lake location. A general correspondence exists between the mineral composition of most freshwater lakes and the average clay mineralogy of rocks and soils in the surrounding drainage basins. Let us consider a few selected examples.