Elevated flux of cosmic spherules (micrometeorites) in Ordovician rocks of the Durness Group, NW Scotland
Limestone samples from the Cambro-Ordovician Durness Group were crushed, aciddigested and searched for evidence of micrometeorites. Eleven melted micrometeorites were extracted from the magnetic fraction of samples from the Balnakeil and Croisaphuill formations near the top of the group. Other formations in the Durness Group did not yield micrometeorites. Only melted spherules with a distinctive d