Mineral Monday!
Formation of pseudotachylytes by Mattia Pistone
A rock undergoing fracturing (dilatant cracking) and friction melting partially melts at lower temperature than frictional melting alone.
#MSACommunications #MineralMonday #pseudotachylyte #pseudotachylite #partialmelting

@barraisland.bsky.social have just joined Bluesky. Home of the best exposures of #pseudotachylite in the UK, around Greian Head and Seal Bay.⚒️🧪

The beaches aren't bad as well😎

Last month I revisited the second best #pseudotachylite location in the Outer Hebrides, on the west coast of South Uist.
I tried to pay more attention to the actual faulting this time🤓, but the breccias are always more photogenic😍
⚒️🧪

This #MeltyMonday here is a #pseudotachylite vein with brecciated "xenoliths", cutting across the foliation in Lewisian gneiss.
The vein extends for about 3m before disappearing under the beautiful white sands of Seal Bay on the W. coast of Barra, in the Outer Hebrides, Scotland.
#Geology ⚒️🧪

This summer I eventually managed to visit the classic #pseudotachylite outcrop on the beach south of Greian Head, (Ceann Aird Ghrein), Isle of Barra, Scotland.
#Geology ⚒️🧪