The day started cold, grey and quite misty, but turned out to be a day very high in ‘twinkle factor’ and sunshine. After an enthusiastic introduction by Diana, we all scampered down the path to the beach, eagerly clutching our hand lens and grain size charts. The tide was in, and I quite anticipated being mown over at any second by a jet ski emerging from the heavy sea mist as we examined the many different types of pebbles (predominantly flint) on the beach. Here we saw that this beach was new sedimentary rock in the process of being formed, and we started to understand how to describe and interpret the characteristics of the pebbles in terms of rounding, sphericity, size, grain size, sorting and hardness.

Above the beach we saw a number of slightly dipping sedimentary beds exposed in a cliff face, including a prominent black pebble layer. We could see many of the pebbles from this layer scattered on the beach and at the foot of the cliffs in the landslips. One of the lecturers (who shall remain unnamed) was overheard to wish for a catapult as she spied one of the students bending over in a most provocative fashion at the top of the cliff. Not what you’d call a usual application of geology..!

We could see evidence of landslips along the foot of the cliff, and Brian gave us a demo of rotational land slips with a super Blue Peter model he had prepared earlier, and he explained the various means of prevention which we could see around us.

Further up the beach, we looked at some of the sea defences which had been erected to protect against the rotational slips. The defences were remarkable for being comprised mostly of igneous and metamorphic blocks which had been shipped by barge all the way from Norway. The lavakite blocks had huge, interlocking crystals, which we learned was indicative of a melt and slow cooling. They had a fantastic ‘twinkle’ factor which became even more apparent later in the day, when the crystal cleavages glittered beautifully in the afternoon sunshine. Here we learned about how to identify rocks containing mafic minerals (dark, heavy – with iron and magnesium) and felsic minerals (pale, light – with quartz and feldspar) and we learned to recite in unison “at least one mafic mineral is present”. We saw the effect of stress and metamorphism in the segregration of the felsic and mastic minerals to form a texture. The sea defences also contained blocks of yellow fine-grained local concretions, that had fallen from the Thanet sand layer in the cliffs above, and greenish blocks containing evidence of bio-turbation and shell fragements from the Harwich formation in the cliffs above.

At the foot of the cliff we practised drawing our own vertical sections to scale, learned how to distinguish between clay and silt (eat it) and even found some fish teeth fossils. At the top of the cliff we were able to examine the upper beds and their boundaries. We saw evidence of climate in desert roses which would have formed by evaporation in a hot climate. We saw evidence of cross bedding, unconformable surfaces, fish fossils, and surface undulations indicative of strong current. We also found selemnite crystals, which prompted Brian’s story about how iron pyrite oxidises so quickly it can use up all the oygen and force mining tunnels to be abandoned.

We all learned a great deal from the excellent and enthusiastic guidance of our accompanying tutors. Many thanks on behalf of all of us to all the tutors and organisers for a most rewarding day out. On a personal front, I also learned some valuable tips on field trip organisation.