In 1930 James Richey and Herbert Thomas, working for the British Geological Survey, completed their mapping of Ardnamurchan, one of four extinct volcanoes on Scotland’s northwest coast that mark the opening of the North Atlantic Ocean 60 million years ago. Their meticulous work revealed that indeed it was an ancient volcano, with the famous ring-like dyke complex indicating the location of the source of the magma which Ritchie and Herbert interpreted to be a series of three magma chambers.
In order to demonstrate their findings which had caused great interest among the geological community, Richey and Thomas held a memorable field trip the following year to which the great and the good in geology at that time were invited – it was here that Arthur Holmes met Doris Reynolds.
For the next 83 years, Richey and Thomas’s interpretation held fast, but a recent study using a 3-D computer model which matches new geophysical surveys, shows that instead of three magma pulses, just one big injection of magma formed the Ardnamurchan volcano.
