Improved methods for sampling, photographing and varve-counting of varved lake sediments

An improved crust-freeze sampler for taking undisturbed cores of the surface sediments from ice-covered lakes is described together with a technique for subsampling the frozen sediment. Hints are given on how photography and varve-counting in frozen and in fresh cores of varved lake sediments can be made easier, and on how to make thin sections of sediments for examination under the light microscope