Sediment sequences

At each exposed floodplain sediment sample site clear the surface humus and litter to begin with, and then cut a vertical section through the exposed floodplain sediment sequence with a steel spade, thus exposing a clean vertical surface for sampling. If you collect both top and bottom samples, sample the bottom layer first at each sample site, and then the top layer. This procedure avoids cleaning the surface of the bottom layer from fallen top sample material, if the latter is taken first. 

If it is not possible to sample an exposed floodplain sediment sequence with the aid of a spade, follow the same procedure to select a suitable sample site on the floodplain (e.g., inside meander) and dig a pit down to the required depth. 

Samples were selectively taken from the most bitumen-rich layers in the four wells and thus are not representative of the entire sediment sequence in the Nordlinger Ries. 

Gavish E. and Friedman G.M. (1969) Progressive diagenesis in Quaternary to Late Tertiary carbonate sediments sequence and time scale. J. Sediment. Petrol. 39, 980-1006. 

Jackson T. A. (2001a) Variations in the isotope composition of mercury in a freshwater sediment sequence and food web. Can. J. Fish. Aquat. Sci. 58(1), 185—196. 

Figure 7.5 Schematic diagram showing the sediment sequence in the Upper Marsh pit (site UMl) and creek bank (UCRK) profiles.

Snowball, I. F., P. Sandgren G. Petterson, 1999. The mineral magnetic properties of an annually laminated Holocene lake sediment sequence in northern Sweden. The Holocene 9. 353-362. 

Bums (1963) described some possible mistakes using information from cores obtained by piston-type cores. A simple experimental setup resulted in some interesting data on different sediment sequences. Fewer mistakes in sediment sequence occurred at full rather than at partial penetrations. 

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