My walk of May 19, 2009 was along all the Southend-on-Sea beaches at the latest high tide mark (relatively low 4.6 m predicted range). It started with the discovery of a fossil elephant limb bone fragment on East Beach near the Sea Life Centre. Although formal identification depends on the discovery of the teeth, it seems probable from the size and degree of secondary post-depositional dark phosphate cementation of the white bone, that it came from the Steppe Mammoth Mammuthus trogontherii Pohlia. Mammoth species are not generally as large as modern African Elephants, but this particular species was as large as the largest known specimens in the larger sample known to Big Game Hunters and culls in Africa. It was at least 14 feet (14.3m) high at the shoulder and yielded a more intact thigh bone (femur) from Mundesly Beach (Norfolk coast) with a length of 5 feet (1.5m) [A. Lister & P. Bahn Mammoths, MacMillan N.Y. 1994, p.24 x 68]. The East Beach fragment looks like the part of this femur, which is anticlastically curved as it expands into the base of the epiphyses. It has a transverse radius of curvature of 0.116 metres, indicative of a circumference approaching 0.73 m even on the narrower shaft. The axial length parallel to the trabeculae (spaced 1.0± 0.2 mm apart) is 125 mm and a width around 80 mm. The hidden thickness of the bone around the missing marrow cavity is 25 to 30 mm. It shows a transition from a smooth cortex to the pores with 0.3 mm sand, cemented by hydrated iron oxides. The Mundesly bone photograph suggests that a circumference in the unfolded anticlastic region near the epiphyses of around 0.73 m, is equivalent to a minimum shaft circumference around 0.55 m in a femur of 1.5 m length.
A second bone fragment came from the strandline between Walton and Lynton Roads, during a walk on June 26, 2009. This represents the more externally porous surface of an epiphysis with a radius of curvature of only 30 mm. Being less cemented it probably came from a younger Pleistocene deposits than the Cromer Forest-Bed yielding M. trogontherii and the straight Tusked Elephant Palaeoloxodon antiquus (Falconer & Cautley)[another possible source of large bone fragments]. This smaller bone fragment (63 by 38 by 34 mm dimensions) could easily be confused with the pebbles of aerated concrete building blocks often seen in the same strandline; but it differs from them in being denser than seawater and having elongated pores.
The reason why these bones occur at Southend is that gravel was dredged from the North Sea and pumped from the dredgers to reinforce the beach in a large diameter pipeline. The pipeline was moved west from St. Thorpe Hall Avenue to Southend East Beach during the summer of 2002. I visited East Beach showing underlying London Clay when this was going on in June 21, 2002. Due to the gradual process of deposition of new gravel (from east to west if my memory is correct) there are different fossils and concretions related to particular spots along the strandline, even though all of them have been dredged from the North Sea sites. One can deduce that the source seabed was a thin or partial cover of flint and sarsen gravel on London Clay containing concretions, some concretions were bored in the North Sea by the modern bivalve Barnea pendula Pennant. According to Jeff Saward, who collected from the Southend beach in the winter of 2002-3, this source area was “12 miles of Felixstowe” and yielded a mammoth tooth as well as mammoth bone to him then (see report on his talk of September 2003 by Roger Coleman on pages 3-4 of Essex Rock and Mineral Society Newsletter, Number 237, October 2003)
Outside the area between central Thorpe Bay and Southend Pier, gravel has been added from time to time by trucks from other sources, which do not appear to contain large fossils. Here the London Clay is still present on the beach and is still a source of the grey insitu finds still also available at East Beach in 2010.
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