De Geer's Swedish Time Scale underwent the first of many revisions, as other geologists became involved in the study of varves and more sites were examined.
22.
The bitter dispute between De Geer and Antevs, coupled with the advent of new dating techniques, most importantly radiocarbon dating, showed varves in a bad light.
23.
Some observations of varves ( layers seen in the mud covering the bottom of lakes ) matched the prediction of a Milankovitch cycle lasting about 21, 000 years.
24.
Paleoclimatology dates back to the 19th century, and the concept of examining varves in lake beds and tree rings to track local climatic changes was suggested in the 1930s.
25.
As a consequence, the sediments at the bottom of Lower Mystic Lake accumulate in annual layers ( or varves ) that have been nearly undisturbed for a thousand years.
26.
As the varves get closer to the shoreline the clay layer will stay relatively the same thickness, but there will be an increase in thickness of the silt layer.
27.
As a result, the mud at the bottom of the lake is made of alternating black and white layers ( or varves ) representing different seasons of the year.
28.
"' Parting-step lineation "', which is characterized by step-like parting surfaces, has been reported by Banerjee from varves deposited in glacial lakes.
29.
Till is deposited at the terminal moraine, along the sandurs by the rivers flowing from the glacier, and as varves ( annual layers ) in any proglacial lakes which may form.
30.
It experienced annual layering of sediments, or varves : silt and sand in the summertime ( due to glacial meltwater ) and clay in the wintertime ( as the lake froze ).
