COUNTRYSIDE COUNCIL FOR WALES
SITE OF SPECIAL SCIENTIFIC INTEREST: CITATION
ANGLESEY HENBORTH
National Grid Reference: SH321931
Site Area: 11.3 ha
This site is selected for its geomorphological interest.
Hen Borth provides a rare and excellent exposure through the long axis of a drumlin, clearly revealing the internal structure and composition of the feature. The deposits comprise mainly stony till derived from the Irish Sea basin to the. north, with weathering and cryoturbation features developed in the upper part of the sections. In the northern part of the bay, the sequence, of Pleistocene deposits is more complex. Here, a lower head is overlain and incorporated within the overlying till, which in turn is succeeded by soliflucted till and an upper head deposit. In the upper part of the sequence, cryoturbation structures and frost wedges again provide striking evidence for periglacial conditions. Such exposures through drumlins are rare not only in Wales but throughout Britain, and Hen Borth is a particularly fine example. The combination of sedimentary detail and the quality of exposure therefore make Hen Borth a site of considerable interest for the study of drumlin formation.