WGCG Spring 2021 Newsletter - Flipbook - Page 7
WGCG
Spring 2021 Newsletter
After a short lunch break, we made our way towards Drumadoon sill, a 30-metre-high feature with a sea
stack. The base of the sill is composed of a sheet of tholeiite, which thins from around 1.2 metres to
approximately 0.8 metres at the south end of the sill (McDonald, 2015). The main body of the structure is
composed of columnar-jointed quartz-feldspar porphyry (McKerrow and Atkins, 1989).
Drumadoon sill
Photo credit: Paul Abernethy
Day 3 saw us travelling to the Corrie foreshore, where there are numerous beautiful examples of finely
bedded sandstone structures and, interestingly, a fulgurite. This, we were told, is a fossilised lightning strike
formed when lightning strikes sand, melting the silica and fusing it together as it cools.
Fulgurite on Corrie foreshore
Photo credit: Deborah Parke
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