Concluding remarks

• Published in: Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Royal Society 1965
• Subjects: Greenland; Spitzbergen
• Online Access: http://dx.doi.org/10.1098/rsta.1965.0043; https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.1965.0043

There have been two threads running through this Symposium: the interpretation of observations and the discussion of mechanisms. Nearly all the speakers concerned with the evidence derived from the comparison of the continents and from palaeomagnetism have interpreted their results in terms of movement of the continents. It is difficult not to be impressed by this agreement of many lines of study leading to compatible conclusions, though there have been some dissenting views. The most troublesome differences of opinion about the interpretation of the facts relate to the distribution of plants and animals in the past. Perhaps it is not surprising that there should be differences here; the fossil record is incomplete both in time and in space and, if one believes that arbitrarily great changes of climate may have occurred in the past and perhaps also that the Earth’s poles may have shifted, there is not much information left to determine whether the continents have moved relative to each other or not. For example there are Carboniferous evaporites in Spitzbergen and Permian evaporites in Greenland where they are not forming today. Conditions in the past must have been different from those of the present, but if one asks whether such different conditions existed in a belt running all round the pole in the latitude of Spitzbergen, and thus indicate a general change in climate, one cannot tell, because most of the area is occupied by Precambrian shields. Climatic change, continental movement and shifts of the pole, are all possible explanations.