Magnitude frequency study of rockfall in Co. Antrim, N. Ireland

Detailed observations of rockfall were kept on a weekly basis over a two year period. The results indicate that there is both a seasonal distribution of rockfall with maxima in February‐March and November–December, and continuous small scale rockfall throughout the year. There appears to be some connection between rockfall and frost processes, while the peculiar geotechnical properties of the lava flows in county Antrim, in particular the presence of microfractures, would seem to be the main underlying cause for the observed activity.