Boxgrove Quarry
Boxgrove Quarry , also known as Amey's Eartham Pit , is an old Paleolithic site on the outskirts of Boxgrove in West Sussex , southern England . The main find layer comes from the late Cromer complex and has a geological age of at least 500,000 years.
Most of the sites in the Boxgrove Quarry 1 (location) and Boxgrove Quarry 2 (location) gravel pits were excavated between 1983 and 1996 by a team from the Institute of Archeology at University College London , led by Mark Roberts . The site is on an eroded chalk cliff. Near Seaford, about 75 km to the east, the geologically similar chalk deposits ( Seven Sisters Formation) tower over the sea to this day.
Stratigraphy / geology
Since the site of the discovery is an open gravel pit, which in places had already been driven a few meters deep, stratigraphic profiles of several meters, horizontally and vertically, could be created, which enable a good reconstruction of the regional landscape development.
The deposits of the lower layers, lying directly on the adjacent chalk cliff and interspersed with larger chalk chunks at the base, are known as Slindon Sands . Their fine-grain structure is due to the erosive effect of the water movements of the ocean surf, which once reached right up to the cliff. Due to the tectonic uplift of the coastal region by 5–7 m, the coastline receded to the south and a lagoon formed in the run-up to the cliff, which subsequently dried out further, formed a grassy landscape and changed into a swampy landscape due to renewed flooding. The deposited lagoon in the silts are as Slindon Silts ( Silt = silt ;) and contain characteristic components of both landscape organic phase after sedimentation. Slindon Sands and Slindon Silts together form the Slindon Formation , which was deposited during an interglacial . The transition to a pronounced glacial can be seen in the sediments of the overlying layers ( Lower Eartham Gravel Member ) . Roberts and Parfitt name the Anglian Glaciation (corresponds to the Elster Cold Age in Central Europe) as the most likely climatic phase for the shift package known as the Upper Eartham Gravel Member . Lower and Upper Eartham Gravel Members make up the Eartham Formation . These layers are characterized by coarser gravel, which is composed of the limestone cliff that has been eroded by the glacial conditions.
paleontology
In the course of the geological investigations, palaeontological observations were made, whereby the fossils and microfossils embedded in the rocks and sediments were examined and determined in more detail.
It could foraminifera and ostracods are observed, the rising and falling again biodiversity , ie the variety of coexisting species is climate dependent and correspond with the assumed interglacial. Traces of the ichthyofauna in the Slindon Sands have shown that the sea once reached as far as the cliff , but various mollusks are also evidence of this.
fauna
During the excavations, numerous remains of bones from various animals were recovered in the individual layers. This enables the reconstruction of the fauna as a whole, but above all the reconstruction of fauna communities during the formation of individual layers. In addition, preferred climatic conditions are known for many animal species, which in turn allows conclusions to be drawn about the prevailing temperatures, amounts of precipitation and the like at different times.
In addition to the avifaunal remains of a duck (several bones of a wing) and the individual bone fragment of a giant alkali ( Pinguinus impensis ), the mammals (Mammalia) form the largest group among the fauna remains. The wolf ( Canis lupus ), of which a complete skull, numerous mandibles (lower jaw) and other skeletal parts have been found, is the most common large carnivore , followed by the (cave) bear ( Ursus deningeri ). Among the small carnivores, the mink ( Mustela lutreola ) is the most common representative. The badger ( Meles sp.) Could only be detected with a single specimen. For the large cervids , the red deer ( Cervus elaphus ) was observed most frequently, followed by the roe deer ( Capreolus capreolus ), while the bison ( Bison cf. schoetensacki ) represents the bovids with a few remains . Among the odd-toed ungulates , two rhinoceros are to be emphasized ( Stephanorhinus hundsheimensis and Stephanorhinus megarhinus ). Furthermore, the mole ( Talpa minor ) and the beaver ( Castor fiber ) are also represented among others.
Dating methods used
Various dating methods were used to determine the age of the site .
Uranium Thorium Dating: Four Boxgrove bones were analyzed using uranium thorium dating . From the results, however, it could only be deduced that the bones must be older than 350,000 years.
Luminescence dating: sediment samples / clay were examined. The samples examined by thermoluminescence dating showed a minimum age of 175,300–319,900 years with an extremely high error range of up to ± 93,800 years. Something similar could be observed with OSL dating ( optically stimulated luminescence ). One sample was 356,000 ± 178,000 years old, a second sample was 630,000 ± 125,000 years old, and a third sample was 560,000 ± 330,000 years old.
ESR electron spin resonance: Two teeth from the rhinoceros and deer were examined using the electron spin resonance method. The majority of the results are between 190,000 and 244.00 years with error ranges from +151,000 to −89,000 years. The most likely time window of the investigation data is given as 205,000–281,000 years. However, the results do not rule out a possible average age of 303,000–339,000 years.
Amino acid dating: The amino acid dating was applied to molluscs and foraminifera. The majority of the results point to the oxygen isotope level 11 (362,000–423,000 years), some up to level 13 (478,000–524,000 years).
Paleomagnetism: The paleomagnetic investigations of the sediments only allowed the conclusion that their polarization speaks for sedimentation during the Brunhes phase and that the deposits are therefore less than 780,000 years old.
Investigation of calcareous nanoplankton: The calcareous nanoplankton contained in sediment samples was deposited between oxygen isotope levels 12 and 8, mainly during level 11.
Biostratigraphy: The biostratigraphy indicates the oxygen isotope level 13.
Summary: The uranium-thorium dating and paleomagnetism results show a dating range between 350,000 and 780,000 years ago. The other investigation methods produced different results, but essentially they fluctuate between the oxygen isotope levels 13 and 11. Roberts and Parfitt tend to be classified in the OIS 13 before the Anglian Glaciation .
Archaeological finds
Numerous stone tools , mainly more than 400 hand-axes of the Acheulean , but also a few scratches and scrapers , and especially the discount remains of the processing are among the anthropogenic found objects. The flint used was created and contained in large quantities in the limestone cliff directly on site. On some bones, traces of cut and chopping from cutting up, and on some tools macroscopic traces, which indicate a use for cutting up the prey, could be observed.
A semicircular hole in the scapula of a horse could be the entry channel of a lance or a spear . However, it is doubtful whether the finds actually prove the hunt for these animals, because no definite hunting weapons were found. The various early homo species have been shown to have mainly fed on carrion . When exactly the transition to active hunting took place has not yet been clarified beyond doubt. The oldest evidence of prehistoric hunting weapons are the Schöningen spears , the age of which is estimated to be around 300,000 years BP .
Skeleton finds
In December 1993, fragments of a tibia were found (archive name Boxgrove 1 ), the oldest human remains in the British Isles. Anthropological research has shown that they belonged to a man about six feet tall and weighing 80 kilograms, who died between the ages of 35 and 40. Since the assignment of fossils to a species is made primarily through skull features, the assignment through a tibia alone is quite difficult. Roberts and Parfitt have therefore measured and compared various tibial fragments from other sites. Since the find in Boxgrove is the only non- skull bone find of an individual of the hominini in northern Europe, they had to fall back on specimens that were geographically further away. The test results only allow the statement that Homo erectus , Homo heidelbergensis , Neanderthals and anatomically modern humans could come into question. Due to the dating of the site, the tool forms (hand ax), biostratigraphy and the climate-specific biodiversity and, to a greater extent, the geology, in a time range of around 500,000 BP, the assignment of the tibia to anatomically modern humans can be ruled out; the most likely candidate is Homo heidelbergensis . Both ends of the bones also show gnawing marks, which means that the Boxgrove humans were prey or their corpses for other animals.
In 1996, two incisors from another individual were found. You could see periodontal diseases on it, but also cut marks here. However, these were not interpreted as evidence of cannibalism , but rather for the use of stone tools near the mouth and corresponding accidents .
In 2003, English Heritage announced that it wanted to acquire the site in order to enable further excavations and to protect the complex.
literature
- M. Breda, SE Collinge, Simon A. Parfitt, Adrian M. Lister: Metric analysis of ungulate mammals in the early Middle Pleistocene of Britain, in relation to taxonomy and biostratigraphy. I: Rhinocerotidae and Bovidae. In: Quaternary International. Volume 228, 2010, pp. 136-156.
- Michael W. Pitts, Mark Roberts: Fairweather Eden: life in Britain half a million years ago as revealed by the excavations at Boxgrove. Century, London 1997.
- Mark Roberts, Simon Parfitt: Boxgrove, a Middle Pleistocene hominid site at Eartham Quarry, Boxgrove, West Sussex (= Archaeological report. Volume 17). English Heritage, London 1999.
- Mark B. Roberts, Simon A. Parfitt, MI Pope, FF Smith: Boxgrove, West Sussex: Rescue excavation of a Lower Palaeolithic landsurface (Boxgrove Project B, 1989-1991). In: Proceedings of the Prehistoric Society. Volume 63, 1997, pp. 303-358.
Individual evidence
- ↑ Roberts / Parfitt 1999, p. 3
- ↑ Roberts / Parfitt 1999, p. 155
- ↑ Breda et al. 2010, pp. 153-154
- ↑ Breda et al. 2010, pp. 140-144
- ↑ Roberts et al. 1997, pp. 346-350
- ↑ Roberts / Parfitt 1999, pp. 291-307
- ↑ Roberts / Parfitt 1999, p. 303
- ↑ Roberts / Parfitt 1999, p. 303
- ↑ Chris Stringer : The Origin of Our Species. Penguin / Allen Lane, 2011, p. 67. ISBN 978-1846141409 .
Coordinates: 50 ° 51 ′ N , 0 ° 43 ′ W