Published online by Cambridge University Press: 01 May 2009
In what follows, it is proposed to give a general description of the effects of contact-metamorphism, observed in the rocks altered by the intrusion of the Great Whin Sill in Durham and Northumberland.
1 In this and following analyses all the iron is reported as ferric oxide, no special determination having been made of the portion which is always present as ferrous oxide. This often causes more or less excess in the totals, but is not of any importance for the purposes for which these analyses were made.