Field trip to Taddiford Gap, Hordle Cliff.

Hordle cliff is composed of sands and clays of the Headon Hill formation (Late Eocene) that are also found on the northwest coast of the Isle of Wight. It is an SSSI because of the rare vertebrate fossils found there. Certain horizons also yield leaves and seeds. The section is about 25meters thick but, as the dip is only about 2 degrees and the exposed part of the cliff often less than 5 meters high, it outcrops over a distance of about 2 kilometres. In that distance 32 beds, some subdivided, have been recorded. Although the section in Tertiary Research 18 (1-2) pages 35-50, is well described, we have found it very difficult to distinguish the beds in the field.

The top of the cliff is capped by gravel and the base by vegetation covered slumps so that only occasional vertical sections of undistorted strata are exposed. The field trip took place on 10th August 2002 with only Peter Wilcox, Martin Rayner and myself in attendance. Parking is at SZ 264925 on the B 3058 half way between Milford on Sea and where it crosses the A 337 in New Milton. There is a parking meter which requires several pounds for a full day. Walk along the path to the sea at Taddiford gap. Immediately below the cliff top on the left (Looking out to sea) is an exposure of grey silty sand with a gastropod shell bed at the base and, usually, a lot of water coming out of the cliff just below it. This we think is bed 9 and contains small mammalian teeth, mostly from the rodent, Thalerimys headonensis.

On the field trip much of this bed was covered by a small cliff fall so most of the collecting was done on the talus, looking for patches of white Viviparous shell. The larger fossils found this way included several crocodile teeth and some turtle scute. Martin had hurt his back some time ago so was being careful with it, so decided to explore along the beach towards Milford on Sea. About 250 paces from the Gap he found pieces of fish scale and teeth in situ and reported back to us so we all returned to that spot. The technique is to dig into the seam of shell, in this case bivalves, indicating possibly bed 15, the Crocodile bed, (though Martin thinks it may be higher) and then sieve the sand and silt away in a suitable pool on the cliff base. Previously we sieved in the sea which, because of the steep beach and moderate waves, was a moistening experience.

The sieves used were two plastic garden sieves with a metal mesh melted into the bottom. The upper bowl had a 5mm mesh and the lower a 0.5mm mesh. All the material held back was collected in plastic bags, which were then laid on their sides to drain. Using this technique, the contents of a dozen washing up bowls can be reduced to a standard shopping bag. Back home the material is laid out to dry, then re-sieved in fresh water and dried again before being sorted using a low power microscope. I collected 16 mammal teeth from 4 different species, and many fish scales, teeth and bone. Also found were crocodile teeth, bone and scutes, as well as fish otoliths and mollusc shells. An excellent time was had by all, and another trip there is planned for next year. Why don't you come too?