OR/14/052 Appendix 1: Photographic record of sample sites

Boon, D, Kirkham, M, and Scheib, A. 2014. Physical properties of till deposits from Anglesey, north west Wales. British Geological Survey Internal Report, OR/14/052.

Figure 6    Sea cliff cut into drumlinoid landform at Cemlyn Bay, Wilfa Head Nuclear Power Station can be seen on the horizon. Photo taken February 2011.

Figure 7    Sample site at northern end of Cemlyn Bay (17 February 2011). Notice the sequence of red till (top of section) overlying a yellow sand body, and a grey till at the base of the section.

Figure 8    The red till at the top of the sequence at Cemlyn Bay is prone to slumping over the grey till and on to the beach. Photo taken 17 February 2011.

Figure 9    Tight fissures in grey till exposed on the foreshore of Cemlyn Bay. These mechanical discontinuities affect soil mass strength and permeability properties, and assist the coastal erosion process by providing release surfaces. Scale: 10 cm-long grain size card.

Figure 10    Coastal cliff section at Hen Borth, North West Anglesey, exposes internal structure of a drumlinoid landform. The section exposes a basal grey till overlain by an upper red till divided in places by a horizontal body of sand rich material. Slumping of the upper red till onto the beach protects the foot of the slope from wave action, and provides lateral support, until the mass is removed by erosion. Differential weathering exposes cobbles in the till.

Figure 11    Coastal cliff exposure of Grey Till at Hen Borth. The sample site (centre) is marked with a 30 cm long hammer.

Figure 12    Coastal cliff slope at Penrhos site. Note slumping of sands and gravels and red till over grey till. Cliff is subject to wave action and coastal erosion.

Figure 13    Penrhos sampling site (sample PR1 1–2). Excavation in hard till using electric hammer drill with tarpaulin to catch fine fraction. Note how differential erosion has picked out more resistant beds composed of coarse gravel in the upper part of the cliff and the presence of sand lenses (possibly dykes) within grey till approx 1 m above base of cliff.

Figure 14    Exposure of Red till at the Sea Zoo site.

Figure 15    Low coastal cliff exposure at Sea Zoo. Very stiff sheared bright-red mudstone (bedrock) underlies red till. The upper boundary of the mudstone is sharp and planar. The mudstone contains closely spaced wavy veins of hard/extremely weak, mineral filled sub- horizontal spary calcite that display polished surfaces, micro faults, folds the veins are truncate at the mudstone/till interface. Pick axe for scale.

Figure 16    Example of a density ring prior to extraction at the Beaumaris site.

Figure 17    Example of a Panda Penetrometer test set up. Lower Grey Till on the foreshore at Beaumaris test site.

Figure 18    Red till exposed in a low sea cliff near Beaumaris. Notice how the beach is strewn with light-grey sub-rounded, strong, Carboniferous limestone cobbles and boulders probably derived from the red till.

Figure 19    Low coastal cliffs expose Red Till along the Menai Straits passage north of Beaumaris. The red till is rich in limestone cobbles and boulders.

Figure 20    Close up of the Red till at Beaumaris sampling site. Hammer for scale.

Figure 21    Low coastal cliff exposure of Red till at Port Nobla. Bulk sample was taken from 300 mm below boulder. Panda penetrometer test started from hammer location. Note this erratic boulder is approx 2.5 m long composed of weathered granite.

Figure 22    Detail of Red Till sampling site at Port Nobla. Panda test started on cut ledge below hammer tip. Note the deeply weathered smooth/striated granite erratic top left with ‘wrinkled’ surface texture. 30 cm long hammer for scale.