Difficulties in the Glacial Theory
The layer of drift is the main body of evidence for the glacial theory. When one considers how this material is distributed, considerable difficulties arise in the notion that it has been caused by glaciers. It is not present in many areas where one would expect to find it, and it is present where one would least expect it. Thus in the northernmost parts of Greenland, and in some of the islands of northern Canada, no drift is present. But it is found in tropical areas such as the Amazon jungles. Regarding the tropics, right at the equator, no less an authority than Louis Agassiz reported:
There were drift accumulations, and scratched rocks, and erratic boulders, and fluted valleys, and the smooth surface of tillite ...
The presence of drift has been reported from such places as British Guinea, equatorial Africa, Madagascar, and India. Wherever the characteristic features of the drift are found, it seems necessary to postulate former glaciers to explain it. The theory of continental drift is partly an attempt to explain how the ice-sheets could have existed in these areas at various periods in the past.
The glaciers of mountain regions and the ice-sheets of the Antarctic and Greenland do not seem to be forming any deposits similar to the layer of drift that has been attributed to ice-sheets of the past. Present glacial moraines contain fragments of angular rocks unlike the boulders in the drift, which are rounded; and the glacial deposits of the present have none of the features of the structure of the drift, but are more aptly described as a heterogeneous muck. The postulated ice-sheets of North America and Europe are also somewhat lop-sided, and do not conform to the polar regions as one would perhaps expect they should; and accounting for this has been a brain twister for the glacial theorists.
Charles H. Hapgood proposed that the continents were dislocated from time to time from their present relationship with the poles, as the earth's crust shifted over its interior. Hapgood's idea was that the north pole was located in the Yukon 80,000 years ago, shifted to a point northwest of Norway, from there migrated to Hudson Bay, and moved to its present location at the end of the last Ice Age. One reason why this idea has not been afforded very great favor amongst Quaternary geologists is that the structures composed of drift around the world are all very well preserved, and there does not seem to be good reason for attributing some to a much earlier period than others. All of the drift landforms actually must be quite recent, and of similar age, if the degree of erosion is considered as an indicator of age.