Conversations with Professor Prestwich #4
UNCONFORMITIES - AFTER SICCAR POINT

Dear Geoneophytes,

I understand that some of you have been to one of the most famous geological sites on Earth at Siccar Point in southeastern Scotland. I envy you, for I have not visited the spot myself; but I have written extensively on the general subject:

“Unconformity of superposition is one of the features in stratification that it behoves the student to examine with particular care, for it marks a break in continuity, which may indicate a break, both in time and life-forms, of an important character. It is by means also of such want of conformity at various successive periods that the relative ages of mountain-chains are determined.”

Enclosed please find some other examples of unconformity; I expect them to generate a lively debate over dinner.

Cordially,

Joseph Prestwich