At http://cosmictusk.com/dutch-crutch-kloosterman-hits-field-with-pit-sticks/ … Han Kloosterman contracted throat cancer quite some years ago and when he spoke at an SIS meeting at the Harlequin Theatre in Redhill, it was difficult to make out all that he said. He compensated for this with a massive barrage of images to back up what he was saying. It was quite an impressive performance. He is still active, in his 80s, but is now forced to use walking sticks for his geological field trips – quite amazing.
Han Kloosterman is a geologist with a difference. He actively seeks out evidence of catastrophism in the geological record. His focus in recent years has been the Usselo Horizon, which marks the boundary line of the Younger Dryas event. At the Tusk link above there are some images he has taken at various sites in Denmark and Germany, where a clear black charcoal layer is self evident in the Late Pleistocene sequence.
However, being Dutch, he knows much more about the geology of the Netherlands. It is somewhat unique as the Low Countries are so close to sea level – yet dry land separated Holland from England up to halfway through the Holocene. The Pleistocene levels are found on the higher ground – which historically has remained dry and out of reach of known transgression (flooding) events that have struck the Netherlands during the Holocene. Usselo exposures (exposed after digging holes in the ground for various reasons, such as construction, quarrying, drainage etc.) are found on the higher ground in the NE, E and SE parts of Holland – at a depth of between 1 and 2 metres. In the west of the country, closer to sea level, the Usselo Horizon is found at a depth of 18m – in complete contrast. Under Amsterdam the Pleistocene is 20m deep. This indicates a break between Amsterdam and Hilversum, 25 km to the E, where the Usselo is commonly found in contruction holes and pits, not far below the surface. The reason for the difference is simple. In the west clay and peat has been deposited in a thick layer above the Pleistocene geology, and sand dunes which form a protective barrier against inroads by the North Sea, stop the peat and clay being washed away. Clearly these layers were laid down in transgression events – after 3000BC, and most recently in the Late Roman period (as described by Steve Mitchell in the pages of SIS journals, and further embellished by Dick Gagel in letters and at meetings). The fact the transgression events were confined to the western parts of Holland may help to clarify the situation somewhat better than in the past.