This huge capstone rests 5 feet (1.5 metres) above the bottom of a natural fissure in the limestone beneath. The presence of seismically unresolvable sediment-filled fissures in supposedly rigid fault blocks can lead to a significant underestimate of regional extension based on the restoration of motion on normal faults on seismic-reflection profiles The supporting stones were placed along the edge of the hole like a wall to support the capstone. The low supporting stones give it a squat appearance.
When excavated in 1908 bones of several men, women and children were found. There were also remains of animal bones, shells, flint tools, pottery and a bone pin in the chamber. The pottery style indicates it was in use from the late Neolithic to the Early Bronze Age. Limestone Fissures In Anglesey the Carboniferous limestone is cut by numerous fissures that are filled with Mesozoic sediments (sedimentary dykes, neptunian dykes).
The fissures contain a record of Triassic–Lower Jurassic sediments that are only sparingly preserved in their normal stratigraphical position between the Carboniferous Limestone and the unconformably overlying Upper Inferior Oolite of Bajocian age. Most fissures were clearly formed by rapid influx of unlithified sediment from the land surface or sea floor.
Some smaller cavities, or larger cavities with restricted access to the unconformity, were apparently filled by sediment that trickled down into the fissure system. The vast majority of fissures are interpreted as having formed as a response of the Carboniferous Limestone. Such patterns of extension are thought likely to be characteristic of the subsurface geology in much of southern England and Wales.
To log this earthcache please upload a photo of you or your GPSr with the burial chamber in the photo and E-Mail me the answer the following questions
1) What is the weight of the capstone
2) Estimate the circumference of the capstone.
Any logs with no photograph may be deleted,